CN112645967A

CN112645967A - Polycyclic aromatic compound, material containing same, organic electroluminescent element, display device, and lighting device

Info

Publication number: CN112645967A
Application number: CN202011075723.XA
Authority: CN
Inventors: 畠山琢次; 井上大辅; 近藤靖宏; 川角亮介
Original assignee: Kansai College; JNC Corp
Current assignee: Kansai College; SK Materials JNC Co Ltd
Priority date: 2019-10-11
Filing date: 2020-10-09
Publication date: 2021-04-13
Also published as: JP2021063067A; KR20210043466A

Abstract

The invention provides a polycyclic aromatic compound, a material containing the same, an organic electroluminescent element, a display device and a lighting device. The present invention relates to a polycyclic aromatic compound represented by the following formula (1). The present invention can provide a novel compound which is useful as a material for an organic device such as an organic electroluminescent element. Wherein the A ring and the C ring are aryl rings having a substituent such as halogenEtc., rings B and D are aryl rings, etc., at least one of these rings may be substituted with hydrogen, X¹、X²、X³And X⁴Is > O, > N-R, etc., R of > N-R is an optionally substituted aryl, etc., and may be bonded to the A ring, B ring, C ring and/or D ring via a linking group or a single bond, R¹And R²Hydrogen, etc.

Description

Polycyclic aromatic compound, material containing same, organic electroluminescent element, display device, and lighting device

Technical Field

The present invention relates to a polycyclic aromatic compound, a material containing the same, an organic electroluminescent element, a display device, and a lighting device. In addition, the present invention relates to a green light emitting material comprising the polycyclic aromatic compound. The present invention also relates to an organic device such as an organic electroluminescent element, an organic field effect transistor, and an organic thin film solar cell, a display device, and a lighting device, each using the polycyclic aromatic compound.

Background

Conventionally, various studies have been made on display devices using light emitting elements that emit light in an electric field, because they can achieve power saving and reduction in thickness, and further, active studies have been made on organic electroluminescent elements including organic materials because they are easy to reduce the weight and increase the size. In particular, active studies have been made to develop organic materials having light-emitting characteristics such as green, which is one of the three primary colors of light, and to develop organic materials having charge transport capabilities (having the possibility of becoming semiconductors or superconductors) of holes, electrons, and the like, regardless of high molecular compounds and low molecular compounds.

The organic electroluminescent element has a structure including: a pair of electrodes including an anode and a cathode, and one or more layers which are disposed between the pair of electrodes and include an organic compound. The layer containing an organic compound includes a light-emitting layer, a charge transporting/injecting layer for transporting or injecting charges such as holes and electrons, and various organic materials suitable for these layers have been developed.

As a material for a light-emitting layer, for example, a benzofluorene compound has been developed (patent document 1). Further, as a hole transport material, for example, a triphenylamine compound and the like have been developed (patent document 2). Further, as an electron transport material, for example, an anthracene compound has been developed (patent document 3).

In recent years, as a material used for an organic EL device or an organic thin film solar cell, a material obtained by improving a triphenylamine derivative has been reported (patent document 4). The material is characterized by comprising the following components in parts by weight: referring to N, N '-diphenyl-N, N' -bis (3-methylphenyl) -1,1 '-biphenyl-4, 4' -diamine (triphenyldiamine, TPD), which has been put to practical use, the planarity of the aromatic rings constituting triphenylamine is improved by linking the aromatic rings to each other. In the above-mentioned document, for example, the charge transport properties of the NO-linked compound (compound 1 on page 63) were evaluated, but there is NO description of a method for producing a material other than the NO-linked compound, and the properties obtained from the material other than the NO-linked compound are unknown because the electronic state of the whole compound differs depending on the elements to be linked. Examples of such compounds can also be found elsewhere (patent document 5). E.g. having the lowest excited triplet energy level (E)_T1) The compound having a large conjugated structure can emit phosphorescence having a shorter wavelength, and is therefore useful as a material for a blue light-emitting layer. Further, a compound having a novel conjugated structure with a large T1 is also required as an electron transporting material or a hole transporting material which sandwiches the light-emitting layer.

A host material of an organic Electroluminescence (EL) element is generally a molecule in which a plurality of conventional aromatic rings such as benzene and carbazole are connected by a single bond, a phosphorus atom, or a silicon atom. The reason for this is that: by linking a plurality of aromatic rings of relatively small conjugationThe large Highest Occupied Molecular Orbital (HOMO) -Lowest Unoccupied Molecular Orbital (LUMO) gap (band gap Eg in the film) required for the material is ensured. Furthermore, in a host material of an organic EL element using a phosphorescent material or a Thermally Activated Delayed Fluorescence (TADF) material, a high lowest excited triplet level (E) is also required_T1) However, by linking an aromatic ring or substituent of donor or acceptor to the molecule, the Single Occupied Molecular Orbital (SOMO) 1 and SOMO2 of triplet excited state (T1) are localized, and the exchange interaction between the two orbitals is reduced, whereby the lowest excited triplet level (E) can be increased_T1). However, the redox stability of an aromatic ring having a small conjugated system is not sufficient, and the life of an element using a molecule having a conventional aromatic ring linked thereto as a host material is not sufficient. On the other hand, a polycyclic aromatic compound having an extended pi-conjugated system is generally excellent in redox stability, but has a HOMO-LUMO gap (band gap Eg in a thin film) or a lowest excited triplet level (E) _T1) Low and therefore is considered unsuitable for the host material.

In recent years, a compound in which a plurality of aromatic rings are condensed with boron or the like as a central atom has also been reported (patent document 6). In the above-mentioned document, evaluation of an organic EL element using the compound in which a plurality of aromatic rings are condensed as a dopant material of a light-emitting layer has been carried out, but the above-mentioned document discloses an extremely large number of compounds, and it is advantageous to study a compound having excellent organic EL characteristics, particularly light-emitting characteristics and the like.

As a method for forming an organic layer constituting an organic EL element, a wet film formation method is used in addition to a vacuum deposition method. Development of materials for wet film formation methods, particularly inks for forming a hole injection layer, a hole transport layer, and a light-emitting layer, has been actively carried out. Among them, the inks for the hole injection layer and the hole transport layer have been practically used for each layer formed by a wet film formation method using these inks.

[ Prior art documents ]

[ patent document ]

[ patent document 1] International publication No. 2004/061047

[ patent document 2] Japanese patent laid-open No. 2001-172232

[ patent document 3] Japanese patent laid-open No. 2005-170911

[ patent document 4] International publication No. 2012/118164

[ patent document 5] International publication No. 2011/107186

[ patent document 6] International publication No. 2015/102118

Disclosure of Invention

[ problems to be solved by the invention ]

As described above, various materials have been developed as materials used for organic EL devices, but in order to further improve organic EL characteristics such as light emitting characteristics or to increase options for organic EL materials such as materials for light emitting layers, it is desired to develop compounds which have not been known in detail in the past.

[ means for solving problems ]

The present inventors have made extensive studies to solve the above problems, and as a result, have found that an excellent organic EL device can be obtained by using a compound having a specific structure in a polycyclic aromatic compound in which a plurality of aromatic rings are connected by a boron atom, a nitrogen atom, an oxygen atom, or the like, and have completed the present invention. That is, the present invention provides the following polycyclic aromatic compound, and a material for an organic device and the like containing the following polycyclic aromatic compound.

[1] A polycyclic aromatic compound represented by the following formula (1);

in the formula (1), the reaction mixture is,

The A ring and the C ring are each independently an aryl ring having a substituent or a heteroaryl ring having a substituent,

the B ring and the D ring are each independently an aryl ring which may have a substituent or a heteroaryl ring which may have a substituent,

X¹、X²、X³and X⁴Independently of each other > O, > N-R, > CR₂R > N-R is optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl or optionally substituted alkyl, and R > N-R can be bonded to the A, B, C and/or D rings by a connecting group or a single bond,

said > CR₂R of (a) is hydrogen, aryl which may be substituted, heteroaryl which may be substituted, cycloalkyl which may be substituted or alkyl which may be substituted, and, in addition, the radicals > CR₂R of (A) may be bonded to the A ring, B ring, C ring and/or D ring through a linking group or a single bond,

R¹and R²Independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a heteroaryl group having 2 to 15 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), a cyano group or a halogen,

at least one selected from the group consisting of an aryl ring and a heteroaryl ring in the compound represented by formula (1) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, and at least one-CH in the cycloalkane may be substituted ₂-may be substituted by-O-,

at least one hydrogen in the compound represented by formula (1) may be substituted by deuterium.

[2] The polycyclic aromatic compound according to [1], wherein,

ring A is substituted by Z¹Aryl ring of (a) or having one substituent Z¹Or a heteroaryl ring having one substituent Z¹Aryl ring of (a) or having one substituent Z¹Z in the heteroaryl ring of (1)¹Bound to Z by a single bond or a linking group¹The structure of the aryl or heteroaryl ring to which it is bonded,

c ring with one substituent Z²Aryl ring of (a) or having one substituent Z²Or a heteroaryl ring having one substituent Z²Aryl ring of (a) or having one substituent Z²Z in the heteroaryl ring of (1)²Bound to Z by a single bond or a linking group²The structure of the aryl or heteroaryl ring to which it is bonded,

Z¹and Z²Each independently is any one of the following groups:

aryl which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen;

heteroaryl which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen;

diarylamino groups which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen (two aryl groups may be bonded to each other);

Diheteroarylamino which may be substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano or halogen;

arylheteroarylamino which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano or halogen;

alkyl which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen;

cycloalkyl which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen;

aryloxy which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen;

heteroaryloxy which may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano, or halogen;

arylthio which may be substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano or halogen;

Heteroarylthio which may be substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano or halogen;

a cyano group; or

The halogen(s) are selected from the group consisting of,

ring B and ring D are each independently an aryl ring which may be substituted with alkyl, cyano or halogen or a heteroaryl ring which may be substituted with alkyl, cyano or halogen,

ring A and ring B having and including B, X¹And X²The condensed bicyclic structure of the formula (1) has a 5-membered ring or a 6-membered ring bonded in common, and the C ring and the D ring have a structure comprising B, X³And X⁴The 5-or 6-membered ring having a bond common to the condensed bicyclic structure of the formula (1),

R¹and R²Each independently hydrogen, cyano or halogen.

[3] The polycyclic aromatic compound according to [1], which is represented by the following formula (2);

in the formula (2), the reaction mixture is,

R³、R⁴、R⁵、R⁶、R⁷、R⁸、R⁹、R¹⁰、R¹¹and R¹²Each independently is hydrogen or a substituent selected from substituent group X, R⁵～R⁷And R¹⁰～R¹²May be bonded to each other and together with the b-ring and/or the d-ring form an aryl or heteroaryl ring,

at least one hydrogen in the ring formed may be substituted by a substituent selected from substituent group X;

substituent group X:

aryl which may be substituted with aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

Heteroaryl which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

diarylamino groups (two aryl groups may be bonded to each other) which may be substituted with aryl, heteroaryl, cycloalkyl, alkyl, cyano, or halogen;

diheteroarylamino which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

arylheteroarylamino which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

alkyl which may be substituted by aryl, heteroaryl, cycloalkyl, cyano or halogen;

cycloalkyl which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

alkoxy which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

aryloxy which may be substituted with aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

heteroaryloxy which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

arylthio which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

heteroarylthio which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

alkyl-substituted silyl groups which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen;

A cyano group; and

the halogen(s) are selected from the group consisting of,

X¹、X²、X³and X⁴Independently of each other > O, > N-R, > CR₂And > S or > Se,

said > N-R and said > CR₂Each R of (A) is independently any one of the following groups:

an aryl group having 6 to 12 carbon atoms which may be substituted with an alkyl group having 1 to 6 carbon atoms, a cyano group or a halogen;

a heteroaryl group having 2 to 15 carbon atoms which may be substituted with an alkyl group having 1 to 6 carbon atoms, a cyano group or a halogen;

cycloalkyl group having 3 to 12 carbon atoms which may be substituted with alkyl group having 1 to 6 carbon atoms, cyano group or halogen; or

An alkyl group having 1 to 6 carbon atoms which may be substituted with a cyano group or a halogen,

said > N-R and said > CR₂R of (A) may be bonded to the a ring, the b ring, the c ring and/or the d ring through a connecting group or a single bond¹And R²Independently represents hydrogen, alkyl group having 1 to 6 carbon atoms, aryl group having 6 to 12 carbon atoms, cyano group or halogen,

Z¹and Z²Each independently is any one of the following groups:

aryl which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

heteroaryl which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

diarylamino groups which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano, or halogen;

diheteroarylamino which may be substituted by aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

Arylheteroarylamino which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

alkyl which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

cycloalkyl which may be substituted by aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

aryloxy which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

heteroaryloxy which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

arylthio which may be substituted by aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

heteroarylthio which may be substituted by aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen;

a cyano group; or

The halogen(s) are selected from the group consisting of,

Z¹can be reacted with R³And/or R⁴Form a ring by bonding, in which case R³And/or R⁴May represent boron, or may be bonded to two aryl groups of a diarylamino group,

Z²can be reacted with R⁸And/or R⁹Form a ring by bonding, in which case R⁸And/or R⁹May represent boron, or may be bonded to two aryl groups of a diarylamino group,

at least one hydrogen in the compound represented by formula (2) may be substituted by deuterium.

[4]According to [3 ]The polycyclic aromatic compound, wherein X¹、X²、X³And X⁴At least one of (a) is > N-R.

[5] The polycyclic aromatic compound according to [3] or [4], wherein R > N-R represents an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms which may be substituted with a cyano group or a halogen, or an alkyl group having 1 to 4 carbon atoms which may be substituted with a cyano group or a halogen.

[6]According to [3]To [5]]The polycyclic aromatic compound of any one of the above compounds, wherein R is¹And R²Are all hydrogen.

[7]According to [3]To [6 ]]The polycyclic aromatic compound of any one of the above compounds, wherein R is³、R⁴、R⁸And R⁹Are all hydrogen.

[8]According to [3]To [6 ]]The polycyclic aromatic compound of any one of the above, wherein X¹、X²、X³And X⁴Are all more than N-R,

r > N-R is an aryl group having 6 to 10 carbon atoms which may be substituted with an alkyl group having 1 to 6 carbon atoms, a cyano group or a halogen group,

Z¹and Z²Are diarylamino groups which may be substituted by aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen, Z¹And X¹Or X²R of > N-R as R³Or R⁴Boron of (b) is a linking group to bond with the a ring,

Z²and X³Or X⁴R of > N-R as R⁸Or R⁹The boron of (3) is a linking group and is bonded to the c-ring.

[9]According to [3]To [8 ]]The polycyclic aromatic compound of any one of the above compounds, wherein R is⁵、R⁶、R⁷、R¹⁰、R¹¹And R¹²Independently hydrogen, aryl group having 6 to 10 carbon atoms which may be substituted with cyano or halogen, cycloalkyl group having 3 to 12 carbon atoms which may be substituted with cyano or halogen, or alkyl group having 1 to 6 carbon atoms which may be substituted with cyano or halogen.

[10] The polycyclic aromatic compound according to [1], which is represented by formula (1-307), formula (1-313), formula (1-321) or formula (1-331);

in the formula, Me is methyl, and tBu is tert-butyl.

[11] A green light-emitting material containing the polycyclic aromatic compound according to any one of [1] to [10 ].

[12] A material for organic devices, comprising the polycyclic aromatic compound according to any one of [1] to [10 ].

[13] The material for organic devices according to [12], wherein the material for organic devices is a material for organic electroluminescent elements, a material for organic field effect transistors, or a material for organic thin-film solar cells.

[14] A material for a light-emitting layer, which contains the polycyclic aromatic compound according to any one of [1] to [10] and is used for forming a light-emitting layer of an organic electroluminescent element.

[15] An organic electroluminescent element comprising: a pair of electrodes including an anode and a cathode; and a light-emitting layer which is arranged between the pair of electrodes and contains the material for a light-emitting layer according to [14 ].

[16] The organic electroluminescent element according to [15], wherein the light-emitting layer further contains at least one compound selected from the group consisting of a compound represented by the following formula (3), a compound represented by the following formula (4), and a compound represented by the following formula (5);

In the formula (3), L¹Is an arylene group having 6 to 24 carbon atoms,

in the formula (4), L²And L³Each independently an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 30 carbon atoms,

in the formula (5), L⁴、L⁵And L⁶Each independently an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 30 carbon atoms,

at least one hydrogen in the compound represented by each formula is substituted by an alkyl group having 1 to 6 carbon atoms, a cyano group, a halogen or deuterium.

[17] The organic electroluminescent element according to [15] or [16], which comprises an electron transport layer and/or an electron injection layer disposed between the cathode and the light-emitting layer, wherein at least one of the electron transport layer and the electron injection layer contains at least one selected from the group consisting of a borane derivative, a pyridine derivative, a fluoranthene derivative, a BO derivative, an anthracene derivative, a benzofluorene derivative, a phosphine oxide derivative, a pyrimidine derivative, an arylnitrile derivative, a triazine derivative, a benzimidazole derivative, a phenanthroline derivative, a hydroxyquinoline metal complex, a thiazole derivative, a benzothiazole derivative, a thiapyrrole derivative, and an oxazoline derivative.

[18] The organic electroluminescent element according to [17], wherein the electron transport layer and/or the electron injection layer further contains at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, oxides of alkali metals, halides of alkali metals, oxides of alkaline earth metals, halides of alkaline earth metals, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals, and organic complexes of rare earth metals.

[19] A display device comprising the organic electroluminescent element according to any one of [15] to [18 ].

[20] A lighting device comprising the organic electroluminescent element according to any one of [15] to [18 ].

[ Effect of the invention ]

The present invention provides a novel polycyclic aromatic compound. The compound of the present invention can provide a green light-emitting material having high color purity. In addition, the compound of the present invention is useful as a material for an organic device such as an organic electroluminescent element.

Drawings

Fig. 1 is a schematic sectional view showing an organic EL element according to the present embodiment.

Fig. 2 is a diagram illustrating a method for manufacturing an organic EL element on a substrate having a bank portion by an ink-jet method.

FIG. 3 shows the absorption and fluorescence spectra of compounds (1-307).

FIG. 4 shows the absorption and fluorescence spectra of compounds (1-313).

FIG. 5 shows the absorption and fluorescence spectra of compounds (1-321).

[ description of symbols ]

100: organic electroluminescent element

101: substrate

102: anode

103: hole injection layer

104: hole transport layer

105: luminescent layer

106: electron transport layer

107: electron injection layer

108: cathode electrode

110: substrate

120: electrode for electrochemical cell

130: coating film

140: coating film

150: luminescent layer

200: embankment part

300: ink jet head

310: droplets of ink.

Detailed Description

The present invention will be described in detail below. The following description of the constituent elements may be based on typical embodiments or specific examples, but the present invention is not limited to such embodiments. In the present specification, the numerical range expressed by the term "to" means a range including the numerical values described before and after the term "to" as the lower limit value and the upper limit value. In the present specification, "hydrogen" in the description of the structural formulae means "hydrogen atom (H)".

In this specification, the organic electroluminescent element is sometimes referred to as an organic EL element.

In the present specification, the chemical structure or the substituent may be represented by carbon number, but the carbon number in the case where the chemical structure is substituted with a substituent, the case where the substituent is substituted with a substituent, or the like, refers to the carbon number of each of the chemical structure or the substituent, and does not refer to the total carbon number of the chemical structure and the substituent or the total carbon number of the substituent and the substituent. For example, the "substituent B having a carbon number Y substituted with the substituent a having a carbon number X" means that the "substituent a having a carbon number X" is substituted with the "substituent B having a carbon number Y, and the carbon number Y is not the total carbon number of the substituent a and the substituent B. For example, the "substituent B having a carbon number Y substituted with the substituent a" means that the substituent a "(not limited to a carbon number) is substituted with the" substituent B having a carbon number Y "and the carbon number Y is not the total carbon number of the substituent a and the substituent B.

1. A polycyclic aromatic compound represented by the formula (1)

Three kinds of materials, i.e., a fluorescent material, a phosphorescent material, and a Thermally Activated Delayed Fluorescence (TADF) material, are used as light-emitting materials for organic EL displays, but the light-emitting efficiency of the fluorescent material is low, approximately 25% to 62.5%. On the other hand, the emission efficiencies of the phosphorescent material and the TADF material may reach 100%, but both have a problem of low color purity (wide emission spectrum width). In a display, various colors are expressed by mixing light emissions of red, green, and blue, which are three primary colors of light, but if the color purity of each is low, a color that cannot be reproduced appears, and the image quality of the display is greatly reduced. Therefore, in a commercially available display, an optical filter is used to remove an unnecessary color from a light emission spectrum to improve color purity (to reduce a spectral width). Therefore, if the original spectral width is wide, the ratio of removal increases, and therefore, even when the light emission efficiency is high, the substantial efficiency is greatly reduced. For example, the half-value width of the blue emission spectrum of a commercially available smartphone is approximately 20nm to 25nm, but the half-value width of a general fluorescent material is approximately 40nm to 60nm, a phosphorescent material is approximately 60nm to 90nm, and a TADF material is approximately 70nm to 100 nm. In the case of using a fluorescent material, the half-value width is relatively narrow, and therefore, only a part of the unnecessary color needs to be removed, but in the case of using a phosphorescent material or a TADF material, more than half needs to be removed. Under such a background, development of a light-emitting material that achieves both light-emitting efficiency and color purity is desired.

In general, a phosphorescent material is used as a green light-emitting material for an organic EL display.

The green phosphorescent material is a complex compound having a heavy metal atom such as Ir at the center. The green phosphorescent material has a very high efficiency because the emission efficiency is close to 100%, but has a very wide emission spectrum with a half-value width of 60nm to 90nm, which is disadvantageous in terms of substantial efficiency in the production of an organic EL display.

Therefore, patent document 6 (international publication No. 2015/102118) proposes a new molecular design for dramatically improving the color purity of an organic EL material. In the compounds (1 to 401) disclosed in the documents, for example, HOMO is successfully localized in three carbons (black circles) on a benzene ring containing six carbons and LUMO is localized in the remaining three carbons (white circles) by utilizing a multiple resonance effect of boron (electron withdrawing) and nitrogen (electron donating). By the efficient reverse intersystem crossing, the luminous efficiency of the compound is up to 100% at the maximum. Further, boron and nitrogen in the compound (1-401) not only locally form HOMO and LUMO, but also have an effect of suppressing structural relaxation in an excited state by maintaining a firm planar structure by contracting three benzene rings, and as a result, an emission spectrum having a small Stokes shift (Stokes shift) of the peak of absorption and emission and high color purity is successfully obtained. The half-value width of the emission spectrum was 28nm, and color purity was shown to exceed the level of a fluorescent material with high color purity which has been put to practical use.

On the other hand, in the dimer compound such as the formula (1-421), intermolecular stacking is caused by high planarity, and therefore, there is also a problem that the efficiency of the light-emitting element is not sufficiently satisfied.

In patent document 6, the wavelength of the peak of the light emission is not clear in all the disclosed compounds.

Therefore, the present inventors have made diligent studies as a result: by introducing a substituent, the wavelength of the peak of the emission can be adjusted and the device efficiency can be improved. Specifically, it was found that: the polycyclic aromatic compound represented by formula (1) wherein a specific ring is an aromatic ring having a substituent provides an emission spectrum having high color purity in the same skeleton as the dimer compound. The present inventors have also found that the polycyclic aromatic compound represented by the formula (1) exhibits green luminescence. The reason why the emission spectrum with high color purity is realized is considered to be: by introducing the substituent, the proportion of structures existing on the same plane in the entire molecule is reduced, and thus stacking between molecules can be reduced. However, the effect of the polycyclic aromatic compound of the present invention is not limited by the principle.

The polycyclic aromatic compound represented by the formula (1) is preferably a polycyclic aromatic compound represented by the following formula (2).

The a ring and the C ring in formula (1) are each independently an aryl ring having a substituent or a heteroaryl ring having a substituent. In addition, the B ring and the D ring are each independently an aryl ring which may have a substituent or a heteroaryl ring which may have a substituent. The substituents in the a ring and the C ring and the B ring and the D ring are preferably substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diarylamino (two aryl groups may be bonded), substituted or unsubstituted diheteroarylamino, substituted or unsubstituted arylheteroarylamino (amino having aryl and heteroaryl), substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted arylthio, substituted or unsubstituted heteroarylthio, alkyl-substituted silane, cyano or halogen. Examples of the substituent in the case where these groups have a substituent include: aryl, heteroaryl or alkyl.

The ring A and the ring B preferably have a structure including "B (boron)", "X" and the like¹"and" X²"5-or 6-membered ring having a bond shared by the condensed bicyclic structure of the formula (1), wherein the C ring and the D ring preferably have a structure containing" B (boron) "," X (boron) ", and ³"and" X⁴"the condensed bicyclic structure of the formula (1) has a bonded 5-or 6-membered ring in common.

The term "condensed bicyclic structure" as used herein means a structure containing "B (boron)" and "X" shown in the left part of formula (1)¹"and" X²"two saturated hydrocarbon rings condensed. The same applies to the structure of the condensed bicyclic ring in the right part of formula (1). The "6-membered ring bonded in common to the condensed bicyclic structure" means, for example, as shown in the formula (2), an a-ring (benzene ring (6-membered ring)) condensed in the condensed bicyclic structure. The phrase "(a ring) aryl ring or heteroaryl ring having the 6-membered ring" means that the a ring is formed by only the 6-membered ring or by further condensing another ring or the like on the 6-membered ring so as to include the 6-membered ring. In other words, the term "an (A-ring) aryl ring or heteroaryl ring having 6-membered rings" as used herein means that the 6-membered rings constituting all or a part of the A-ring are condensed in a condensed bicyclic structure. About the "B ringThe same applies to the (b ring) "," C ring (C ring) "," D ring (D ring) ", and" 5-membered ring ".

The a ring and the C ring in formula (1) are each independently an aryl ring having a substituent or a heteroaryl ring having a substituent. The number of substituents is not particularly limited as long as it can correspond to the kind of aryl ring or heteroaryl ring, but is preferably one. One substituent may be further bonded to the ring to which it is bonded, thereby forming a ring. In the present specification, one substituent in the A ring is sometimes referred to as Z ¹One substituent in the A ring is referred to as Z²。

That is, the A ring preferably has one substituent Z¹Aryl ring of (a) or having one substituent Z¹Or a heteroaryl ring having one substituent Z¹Aryl ring of (a) or having one substituent Z¹Z in the heteroaryl ring of (1)¹Bound to Z by a single bond or a linking group¹The structure of the aryl or heteroaryl ring to which it is bonded. In addition, the C ring preferably has one substituent Z²Aryl ring of (a) or having one substituent Z²Or a heteroaryl ring having one substituent Z²Aryl ring of (a) or having one substituent Z²Z in the heteroaryl ring of (1)²Bound to Z by a single bond or a linking group²The structure of the aryl or heteroaryl ring to which it is bonded. More preferably, both of the A ring and the C ring have any preferred form.

As to the preferred bonding position of the substituent, it will be described later.

The ring A (or ring B, ring C, ring D) in the formula (1) corresponds to the ring a in the formula (2) and the substituent Z thereof¹、R³And R⁴(or b Ring and its substituent R⁵Substituent R⁷C ring and its substituent Z²、R⁸And R⁹D ring and its substituent R¹⁰Substituent R¹²). That is, the formula (2) corresponds to the formula in which "A ring to D ring having 6-membered ring" are selected as the A ring to D ring of the formula (1). The rings of formula (2) are represented by the lower case letters a to d in the meaning indicated above.

R in the formula (2)³、R⁴、R⁵、R⁶、R⁷、R⁸、R⁹、R¹⁰、R¹¹And R¹²Each independently is hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio, alkyl-substituted silyl, cyano, or halogen. At least one hydrogen of the aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio, or alkyl-substituted silane groups at this time may be substituted with an aryl, heteroaryl, alkyl, cyano, or halogen.

In the formula (2), the substituent R of the b ring⁵Substituent R⁷And/or substituents R of the d ring¹⁰Substituent R¹²May be bonded to each other and together with the b-ring and/or the d-ring form an aryl or heteroaryl ring, at least one hydrogen in the ring formed may be substituted by aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio, alkyl-substituted silane groups, cyano or halogen. At least one hydrogen of the aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio in this case may be substituted by aryl, heteroaryl, alkyl, cyano or halogen. Therefore, the compound represented by the formula (2) has a structure of a ring constituting the compound changed according to the bonding form of the substituents in the b-ring and the d-ring to each other as shown in the following formula (2-1). The ring B 'and the ring D' in the formula (2-1) correspond to the ring B and the ring D in the formula (1), respectively. The symbols in the formula (2-1) are defined as in the formula (2).

The B 'ring and D' ring in the formula (2-1) are represented by the substituent R in the formula (2)⁵Substituent R⁷And a substituent R¹⁰Substituent R¹²The adjacent groups in (b) are bonded to each other and form an aryl ring or a heteroaryl ring together with the b-ring and the d-ring, respectively (may also be referred to as a fused ring formed by condensing other ring structures in the b-ring or the d-ring). Further, according to the formula (2-1): r of ring b⁷R with ring d¹²It does not correspond to "adjacent radicals to each other", they are not bonded. That is, the term "adjacent group" refers to a group adjacent to the same ring. In addition, Z¹May be bonded to the A ring (a ring) by a connecting group or a single bond, and Z²The C ring (C ring) may be bonded to the C ring by a linking group or a single bond, and when the C ring is bonded to the C ring, the ring structure is changed in the same manner as the B 'ring and the D' ring.

For example, the compound has a B 'ring (or D' ring) formed by condensing a benzene ring, an indane ring (including a dimethyl substituent, etc.), an indole ring, a pyrrole ring, a benzofuran ring, a benzothiophene ring, a cyclopentane ring, and a cyclohexane ring with respect to a benzene ring as a B ring (or D ring), and the condensed ring B '(or the condensed ring D') is a naphthalene ring, a fluorene ring (including a dimethyl substituent, etc.), a carbazole ring, an indole ring, a dibenzofuran ring, a dibenzothiophene ring, an indane ring, or a tetrahydronaphthalene ring.

X in the formulae (1) and (2)¹、X²、X³And X⁴Independently of each other > O, > N-R, > CR₂And > S or > Se. R > N-R is optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl or optionally substituted alkyl, and R > N-R is optionally bonded to the A, B, C and/or D rings by a connecting group or a single bond. Said > CR₂R of (a) is hydrogen, aryl which may be substituted, heteroaryl which may be substituted, cycloalkyl which may be substituted or alkyl which may be substituted, and, in addition, the radicals > CR₂R (a) may be bonded to the a ring, B ring, C ring and/or D ring through a linking group or a single bond.

X¹、X²、X³And X⁴Independently of one another, preferably > O or > N-R, more preferably at least one > N-R, the others > O, and even more preferably all > N-R.

As X¹、X²、X³And X⁴R in the above-mentioned N-R is preferably an aryl group which may be substituted or a cycloalkyl group which may be substituted, more preferably a phenyl group which may be substituted, still more preferably a phenyl group which may be substituted by an alkyl group having 1 to 6 carbon atoms, still more preferably an unsubstituted phenyl group or a phenyl group in which at least one meta-position or at least one ortho-position is substituted by an alkyl group having 1 to 4 carbon atoms, particularly preferably an unsubstituted phenyl group or a phenyl group in which both meta-positions are substituted by a methyl group.

R as > N-R and > CR₂The linking group in the case where R in (A) is bonded to the ring A, the ring B, the ring C and/or the ring D is preferably-O-, -S-, -C (-R)₂-or boron as described later. Furthermore, the "-C (-R)₂R of the- (O-X-O) -group is hydrogen or an alkyl group. Examples of the alkyl group include the alkyl groups described later. Particularly preferably an alkyl group having 1 to 6 carbon atoms and further having 1 to 4 carbon atoms (for example, methyl group, ethyl group and the like).

Here, the stipulation that "R > N — R is bonded to the a ring, the B ring, the C ring and/or the D ring by a linking group or a single bond" in formula (1) corresponds to the stipulation that "R > N — R is bonded to the a ring, the B ring, the C ring and/or the D ring by a linking group or a single bond" in formula (2).

The regulation can be represented by a compound represented by the following formula (2-3) and having X¹Or X³A ring structure introduced into the condensed rings B 'and D'. That is, for example, the compound has a structure in which X is introduced into a benzene ring as the b-ring (or d-ring) in the formula (2)¹(or X)³) A compound having a B 'ring (or a D' ring) formed by condensing another ring. The condensed ring B '(or the condensed ring D') to be formed is, for example, a carbazole ring, a phenoxazine ring, a phenothiazine ring, an acridine ring or the like. These rings may have a substituent. Examples of the substituent in this case include: an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a heteroaryl group having 2 to 15 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), a cyano group, or a halogen.

The symbols in the formulae (2 to 3) are defined as in the formula (2).

In the formula (2-3), X is shown¹Or X³A ring structure introduced into the condensed rings B 'and D' but serving as X²Or X⁴R > N-R may be bonded to the a-ring or the c-ring in the same manner, and when bonded, the ring structure may be changed in the same manner as the B 'ring and the D' ring.

In addition, the substituent Z in the formula (2)¹And a substituent Z²The substitution position (b) is defined as the position para to the position bonded with boron in the a-ring and the c-ring. The a ring and C ring of formula (1) are not limited to benzene rings but various aryl rings or heteroaryl rings, and the substitution position of the substituent on these rings is not limited, but as in formula (2), the substitution is preferably performed at a position relatively distant from the position to which boron is bonded, and more preferably at the farthest position. For example, when the ring A is a naphthalene ring, a fluorene ring, or the like, the substituent (represented by Z) is exemplified below¹) Preferred substitution positions of (a). The symbols in each structure are defined as in the formula (2). In the following formula, A is > CR₂、＞NR₂O or S, R is hydrogen, alkyl (preferably C1-C4 alkyl) or phenyl.

R in formula (1) or formula (2)¹And R²Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a heteroaryl group having 2 to 15 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), a cyano group or a halogen. R ¹And R²Hydrogen, methyl, cyano or halogen is preferred, hydrogen, cyano or halogen is more preferred, and hydrogen is even more preferred.

As the substituent for the aryl ring or the heteroaryl ring in the a ring and the C ring of formula (1), preferred is aryl which may be substituted, heteroaryl which may be substituted, diarylamino which may be substituted (two aryl groups may be bonded to each other), diheteroarylamino which may be substituted, arylheteroarylamino which may be substituted, alkyl which may be substituted, cycloalkyl which may be substituted, aryloxy which may be substituted, heteroaryloxy which may be substituted, arylthio which may be substituted, heteroarylthio which may be substituted, cyano or halogen. As the substituent for the aryl ring or the heteroaryl ring in the a ring and the C ring of formula (1), the following substituents are more preferable.

a cyano group; or

A halogen.

Z in the formula (2)¹And Z²Each independently is any of the following groups.

diarylamino groups (two aryl groups may be bonded to each other) which may be substituted with aryl, heteroaryl, alkyl-substituted silyl, cyano, or halogen;

a cyano group; or

A halogen.

As Z¹Or Z²Two aryl groups in the diarylamino group(s) may be bonded to each other. In this case, two aryl groups in the diarylamino group are, for example, as long as they are represented by > SiR₂、＞CR₂(R is hydrogen or an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms)) as a linking group.

In formula (2), Z¹Can be reacted with R³And/or R⁴Form a ring by bonding, in which case R³And/or R⁴May represent boron. In addition, Z²Can be reacted with R⁸And/or R⁹Form a ring by bonding, in which case R⁸And/or R⁹May represent boron.

Z in relation to formula (1) or formula (2)¹And Z²In the above-mentioned aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, aryloxy, heteroaryloxy, arylthio, heteroarylthio, cyano or halogen, and as a substituent for them, aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silane group, cyano or halogen, the description of "aryl", "heteroaryl", "diarylamino", "diheteroarylamino", "arylheteroarylamino", "aryloxy", "heteroaryloxy", "arylthio", "heteroarylthio", "alkyl", "cycloalkyl", "alkoxy", "alkyl-substituted silane group" or "halogen" may be referred to later. Z ¹And Z²All of them are preferably a heteroaryl group such as diarylamino, alkyl, cycloalkyl, aryloxy, and N-carbazolyl, or a halogen.

Z¹And Z²They may be the same or different, but are preferably the same from the viewpoint of ease of synthesis.

Examples of the "aryl ring" of the ring A, ring B, ring C and ring D of the formula (1) include aryl rings having 6 to 30 carbon atoms, preferably aryl rings having 6 to 16 carbon atoms, more preferably aryl rings having 6 to 12 carbon atoms, and particularly preferably aryl rings having 6 to 10 carbon atoms. Furthermore, the "aryl ring" corresponds to the "R" specified in the formula (2)⁵～R⁷And R¹⁰～R¹²The "aryl ring" in which adjacent groups in (b) are bonded to each other and form together with the b-ring and/or the d-ring "and the b-ring (or the d-ring) already contains a benzene ring having 6 carbon atoms, and therefore the total carbon number of the condensed rings in which the 5-membered ring is condensed is 9 carbon atoms which is the lower limit. In addition, Z¹An aryl ring formed by bonding to the A ring (a ring) through a connecting group or a single bond, or Z²The aryl ring formed by bonding to the C ring (C ring) through a linking group or a single bond is also the same.

Specific "aryl ring" may include: a benzene ring as a monocyclic system, a biphenyl ring as a bicyclic system, a naphthalene ring as a condensed bicyclic system, a tribiphenyl ring (m-terphenyl, o-terphenyl, p-terphenyl) as a tricyclic system, an acenaphthene ring, a fluorene ring, a phenalene ring, a phenanthrene ring as a condensed tricyclic system, a triphenylene ring, a pyrene ring, a tetracene ring as a condensed tetracyclic system, a perylene ring, a pentacene ring as a condensed pentacene ring, and the like.

Examples of the "heteroaryl ring" of the a ring, B ring, C ring and D ring of formula (1) include heteroaryl rings having 2 to 30 carbon atoms, preferably heteroaryl rings having 2 to 25 carbon atoms, more preferably heteroaryl rings having 2 to 20 carbon atoms, still more preferably heteroaryl rings having 2 to 15 carbon atoms, and particularly preferably heteroaryl rings having 2 to 10 carbon atoms. Examples of the "heteroaryl ring" include heterocyclic rings containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen as ring-constituting atoms in addition to carbon. Further, the "heteroaryl ring" corresponds to "R" specified in formula (2)⁵～R⁷And R¹⁰～R¹²The heteroaryl ring "in which adjacent groups in (a) are bonded to each other and form a ring b and/or a ring d", and the ring b (or the ring d) already contains a benzene ring having 6 carbon atoms, and thus the total carbon number of the condensed rings in which the 5-membered ring is condensed is 6 carbon atoms as the lower limit. In addition, Z¹A heteroaryl ring formed by bonding to the A ring (a ring) by a linking group or a single bond, or Z²The heteroaryl ring formed by bonding to the C ring (C ring) through a linking group or a single bond is also the same.

Specific examples of the "heteroaryl ring" include: a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring, a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, an isoindole ring, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a 1H-benzotriazole ring, a quinoline ring, an isoquinoline ring, a cinnoline (cinnoline) ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, a carbazole ring, an acridine ring, a phenoxazine ring, a phenothiazine ring, an indolizine ring, a furan ring, a benzofuran ring, an isobenzofuran ring, a dibenzofuran ring, a benzothiophene ring, a furazan ring, a thianthrene ring, and the like.

At least one of the "aryl ring" or "heteroaryl ring" may be substituted with a substituted or unsubstituted "aryl", a substituted or unsubstituted "heteroaryl", a substituted or unsubstituted "diarylamino", a substituted or unsubstituted "diheteroarylamino", a substituted or unsubstituted "arylheteroarylamino", a substituted or unsubstituted "alkyl", a substituted or unsubstituted "cycloalkyl", a substituted or unsubstituted "alkoxy", a substituted or unsubstituted "aryloxy", a substituted or unsubstituted "heteroaryloxy", a substituted or unsubstituted "arylthio", a substituted or unsubstituted "heteroarylthio", an alkyl-substituted silane group, a cyano group or a halogen as a first substituent, in particular, the "aryl ring" or "heteroaryl ring" in the a ring, C ring is substituted by either. As said first substituent, an aryl group such as "aryl", "heteroaryl", "diarylamino", a heteroaryl group such as "diheteroarylamino", an aryl group such as "arylheteroarylamino", an aryl group such as "heteroarylalkyl", and a heteroaryl group such as "aryloxy", an aryl group such as "heteroaryloxy", an aryl group such as "arylthio", and a heteroaryl group such as "heteroarylthio", there may be mentioned a monovalent radical of said "aryl ring" or "heteroaryl ring".

Specific "aryl" groups include: phenyl as a monocyclic system, biphenyl as a bicyclic system, naphthyl (1-naphthyl or 2-naphthyl) as a condensed bicyclic system, terphenyl (m-terphenyl, o-terphenyl or p-terphenyl) as a tricyclic system, acenaphthyl, fluorenyl, phenalkenyl, phenanthryl as a condensed tricyclic system, triphenylene, pyrenyl, tetracenyl as a condensed tricyclic system, perylenyl, pentacenyl as a condensed pentacyclic system, and the like.

Examples of the "heteroaryl group" (first substituent) include a heteroaryl group having 2 to 30 carbon atoms, preferably a heteroaryl group having 2 to 25 carbon atoms, more preferably a heteroaryl group having 2 to 20 carbon atoms, further preferably a heteroaryl group having 2 to 15 carbon atoms, and particularly preferably a heteroaryl group having 2 to 10 carbon atoms. Examples of the "heteroaryl group" include a heterocyclic ring containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen as ring-constituting atoms in addition to carbon, and the like.

Specific examples of the "heteroaryl group" include: pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, indolyl, isoindolyl, 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiyl, phenoxazinyl, phenothiazinyl, phenazinyl, indolizinyl, furyl, benzofuryl, isobenzofuryl, dibenzofuryl, naphthobenzofuryl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, naphthobenzothienyl, furazanyl, thianthrenyl, and the like.

The "alkyl group" as the first substituent may be either a straight chain or a branched chain, and examples thereof include a straight-chain alkyl group having 1 to 24 carbon atoms and a branched-chain alkyl group having 3 to 24 carbon atoms. Preferably an alkyl group having 1 to 18 carbon atoms (branched alkyl group having 3 to 18 carbon atoms), more preferably an alkyl group having 1 to 12 carbon atoms (branched alkyl group having 3 to 12 carbon atoms), still more preferably an alkyl group having 1 to 6 carbon atoms (branched alkyl group having 3 to 6 carbon atoms), and particularly preferably an alkyl group having 1 to 4 carbon atoms (branched alkyl group having 3 to 4 carbon atoms).

Specific examples of the alkyl group include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2-dimethylheptyl, 2, 6-dimethyl-4-heptyl, 3,5, 5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl and the like.

Further, for example, there can be mentioned: 1-ethyl-1-methylpropyl, 1-diethylpropyl, 1-dimethylbutyl, 1-ethyl-1-methylbutyl, 1, 4-trimethylpentyl, 1, 2-trimethylpropyl, 1-dimethyloctyl, 1-dimethylpentyl, 1-dimethylheptyl, 1, 5-trimethylhexyl, 1-ethyl-1-methylhexyl, 1-ethyl-1, 3-dimethylbutyl, 1,2, 2-tetramethylpropyl, 1-butyl-1-methylpentyl, 1-diethylbutyl, 1-ethyl-1-methylpentyl, 1, 3-trimethylbutyl, 1-propyl-1-methylpentyl, 1-ethylbutyl, 1-methylpentyl, 1,1, 2-trimethylpropyl, 1-ethyl-1, 2, 2-trimethylpropyl, 1-propyl-1-methylbutyl, 1-dimethylhexyl and the like.

Examples of the "cycloalkyl group" as the first substituent include cycloalkyl groups having 3 to 12 carbon atoms. The preferable cycloalkyl group is a cycloalkyl group having 3 to 10 carbon atoms. More preferably, the cycloalkyl group has 3 to 8 carbon atoms. More preferably, the cycloalkyl group is a cycloalkyl group having 3 to 6 carbon atoms.

As specific cycloalkyl groups, there may be mentioned: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and alkyl (particularly methyl) substituents having 1 to 5 carbon atoms thereof, or norbornenyl, bicyclo [1.0.1] butyl, bicyclo [1.1.1] pentyl, bicyclo [2.0.1] pentyl, bicyclo [1.2.1] hexyl, bicyclo [3.0.1] hexyl, bicyclo [2.1.2] heptyl, bicyclo [2.2.2] octyl, adamantyl, diamantanyl, decahydronaphthyl, decahydroazulenyl, and the like.

Examples of the "alkoxy group" as the first substituent include a linear alkoxy group having 1 to 24 carbon atoms and a branched alkoxy group having 3 to 24 carbon atoms. The alkoxy group is preferably an alkoxy group having 1 to 18 carbon atoms (an alkoxy group having a branched chain having 3 to 18 carbon atoms), more preferably an alkoxy group having 1 to 12 carbon atoms (an alkoxy group having a branched chain having 3 to 12 carbon atoms), yet more preferably an alkoxy group having 1 to 6 carbon atoms (an alkoxy group having a branched chain having 3 to 6 carbon atoms), and particularly preferably an alkoxy group having 1 to 4 carbon atoms (an alkoxy group having a branched chain having 3 to 4 carbon atoms).

Specific examples of the alkoxy group include: methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy and the like.

The "alkyl-substituted silyl group" as the first substituent is preferably a trialkylsilyl group. With respect to the alkyl group to be substituted, reference may be made to the description of the "alkyl group" as the first substituent. Preferred alkyl groups for substitution are alkyl groups having 1 to 5 carbon atoms, and specific examples thereof include: methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-pentyl, and the like.

Specific examples of the trialkylsilyl group include: trimethylsilyl group, triethylsilyl group, tripropylsilyl group, triisopropylsilyl group, tributylsilyl group, tri-sec-butylsilyl group, tri-tert-pentylsilyl group, ethyldimethylsilyl group, propyldimethylsilyl group, isopropyldimethylsilyl group, butyldimethylsilyl group, sec-butyldimethylsilyl group, tert-pentyldimethylsilyl group, methyldiethylsilyl group, propyldiethylsilyl group, isopropyldiethylsilyl group, butyldiethylsilyl group, sec-butyldiethylsilyl group, tert-butyldiethylsilyl group, methyldipropylsilyl group, ethyldipropylsilyl group, butyldipropylsilyl group, sec-butyldipropylsilyl group, tert-pentyldipropylsilyl group, methyldiisopropylsilyl group, methyl-propylsilyl group, ethyl, Ethyldiisopropylsilane, butyldiisopropylsilane, sec-butyldiisopropylsilane, tert-amyldiisopropylsilane, etc.

Examples of the "halogen" as the first substituent include: fluorine (F), chlorine (Cl), bromine (Br), iodine (I). Preferably fluorine, chlorine or bromine, more preferably chlorine.

Substituted or unsubstituted "aryl", substituted or unsubstituted "heteroaryl", substituted or unsubstituted "diarylamino", substituted or unsubstituted "diheteroarylamino", substituted or unsubstituted "arylheteroarylamino", substituted or unsubstituted "alkyl", substituted or unsubstituted "cycloalkyl", substituted or unsubstituted "alkoxy", substituted or unsubstituted "aryloxy", substituted or unsubstituted "heteroaryloxy", substituted or unsubstituted "arylthio", substituted or unsubstituted "heteroarylthio" as specified as substituted or unsubstituted, at least one of which may be substituted by a second substituent. Examples of the second substituent include aryl, heteroaryl, alkyl, cyano and halogen, and specific examples thereof are described with reference to the monovalent group of the "aryl ring" or the "heteroaryl ring" and the "alkyl group" or the "halogen" as the first substituent. In the aryl or heteroaryl group as the second substituent, a group in which at least one hydrogen atom is substituted by an aryl group such as a phenyl group (specifically, the group described above), an alkyl group such as a methyl group (specifically, the group described above), a cyano group, or a halogen is also included in the aryl or heteroaryl group as the second substituent. For example, when the second substituent is a carbazolyl group, a carbazolyl group in which at least one hydrogen at the 9-position is substituted with an aryl group such as a phenyl group or an alkyl group such as a methyl group is also included in the heteroaryl group as the second substituent.

R as formula (2)³～R¹²The aryl, heteroaryl, diarylamino aryl, diheteroarylamino heteroaryl, arylheteroarylamino aryl and heteroaryl, aryloxy aryl, heteroaryloxy heteroaryl, arylthio aryl, heteroarylthio heteroaryl in (1) may be a monovalent group of the "aryl ring" or "heteroaryl ring" as defined in the formula. In addition, the first and second substrates are,as R³～R¹²The alkyl group, the cycloalkyl group, the alkoxy group, the alkyl-substituted silyl group or the halogen in (1) can be referred to the description of "alkyl group", "cycloalkyl group", "alkoxy group", "alkyl-substituted silyl group" or "halogen" as the first substituent in the description of the above formula (1). Further, aryl, heteroaryl or alkyl groups as substituents for these groups are also the same. In addition, with respect to R⁵～R⁷And R¹⁰～R¹²Aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio, alkyl-substituted silyl, cyano or halogen as substituents for these rings and aryl, heteroaryl, alkyl, cyano or halogen as further substituents, when adjacent radicals in (a) are bonded to one another and form together with the b-ring or the d-ring an aryl ring or a heteroaryl ring, are also the same.

The emission wavelength can be adjusted by steric hindrance, electron donating property, and electron withdrawing property of the structure of the first substituent. As a substituent for an aryl ring or a heteroaryl ring in the A ring, B ring, C ring and D ring (including Z)¹And Z²) Preferred specific examples of (A) include a group represented by the following structural formula, a cyano group and a halogen. More preferably methyl group, t-butyl group, t-amyl (t-amyl) group, phenyl group, o-tolyl group, p-tolyl group, 2, 4-xylyl group, 2, 5-xylyl group, 2, 6-xylyl group, 2,4, 6-mesityl group, diphenylamino group, di-p-tolylamino group, bis (p- (t-butyl) phenyl) amino group, carbazolyl group, 3, 6-dimethylcarbazolyl group, 3, 6-di-t-butylcarbazolyl group and phenoxy group, more preferred are methyl group, t-butyl group, phenyl group, o-tolyl group, 2, 6-xylyl group, 2,4, 6-mesityl group, diphenylamino group, di-p-tolylamino group, bis (p- (t-butyl) phenyl) amino group, carbazolyl group, 3, 6-dimethylcarbazolyl group, 3, 6-di-t-butylcarbazolyl group and chlorine. From the viewpoint of ease of synthesis, a gene having a large steric hindrance is preferably selectively synthesized, and specifically, a t-butyl group, a t-amyl (t-amyl) group, an o-tolyl group, a p-tolyl group, a 2, 4-xylyl group, a 2, 5-xylyl group, a 2, 6-xylyl group, a 2,4, 6-mesityl group, a, Di-p-tolylamino, bis (p- (tert-butyl) phenyl) amino, 3, 6-dimethylcarbazolyl, 3, 6-di-tert-butylcarbazolyl, and chlorine.

In the following structural formulae, "Me" represents a methyl group, "tBu" represents a tert-butyl group, "tAm" represents a tert-pentyl group, "thoct" represents a tert-octyl group, and a bond site.

*-Me *-tBu *-tAm *-tOct

In the aryl or heteroaryl ring in the A and C rings of formula (1), Z¹And Z²Each independently of the other is said to be any of the preferred substituents, preferably not having Z¹And Z²And (ii) an additional substituent. For example, R in the formula (2) is preferable³、R⁴、R⁸And R⁹Are all hydrogen.

Z¹And Z²The substituents may be the same or different, but the same is preferable from the viewpoint of ease of synthesis.

The aryl ring or heteroaryl ring in the B ring and D ring of formula (1) preferably has one substituent or no substituent. The substituent is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group or a tert-butyl group. For example, R in the formula (2) is preferable⁵、R⁷、R¹⁰、R¹²Are all hydrogen, and R⁶And R¹¹Each independently methyl or tert-butyl.

X of formula (1)¹、X²、X³And X⁴R > N-R in (1) is aryl, heteroaryl, cycloalkyl or alkyl, at least one of which may be substituted by aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio, alkyl-substituted silyl, cyano or halogen. Examples of these groups or substituents substituted on these groups include those described above. Particularly preferred are aryl groups having 6 to 10 carbon atoms (e.g., phenyl group, naphthyl group, etc.), heteroaryl groups having 2 to 15 carbon atoms (e.g., carbazolyl group, etc.), and alkyl groups having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, etc.). The description is for X in formula (2) ¹、X²、X³And X⁴The same applies to the other.

X of formula (1)¹、X²、X³And X⁴In (b) > CR₂R of (A) is hydrogen, aryl, heteroaryl, cycloalkyl or alkyl, at least one of which may be substituted by aryl, heteroaryl, diarylamino, or alkyl,Diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, heteroaryloxy, arylthio, heteroarylthio, alkyl-substituted silyl, cyano or halogen substitution. Examples of these groups or substituents substituted on these groups include those described above. Particularly preferably an alkyl group having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, etc.). The description is for X in formula (2)¹、X²、X³And X⁴The same applies to the other.

R for formula (1) or formula (2)¹And R²In the above description, for more details of the alkyl group having 1 to 6 carbon atoms, the aryl group having 6 to 12 carbon atoms, the heteroaryl group having 2 to 15 carbon atoms or the diarylamino group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), the "alkyl group", "aryl group", "heteroaryl group" or "diarylamino group" may be referred to.

At least one selected from the group consisting of an aryl ring and a heteroaryl ring in the compound represented by formula (1) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, and at least one-CH in the cycloalkane may be substituted ₂-may be substituted by-O-.

Examples of the "cycloalkane" include: a C3-24 cycloalkane, a C3-20 cycloalkane, a C3-16 cycloalkane, a C3-14 cycloalkane, a C5-10 cycloalkane, a C5-8 cycloalkane, a C5-6 cycloalkane, a C5 cycloalkane, and the like.

Specific examples of the cycloalkane include: cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornene, bicyclo [1.0.1] butane, bicyclo [1.1.1] pentane, bicyclo [2.0.1] pentane, bicyclo [1.2.1] hexane, bicyclo [3.0.1] hexane, bicyclo [2.1.2] heptane, bicyclo [2.2.2] octane, adamantane, diamantane, decahydronaphthalene, decahydroazulene, and alkyl (particularly methyl) substituents, halogen (particularly fluorine) substituents and deuterium substituents each having 1 to 5 carbon atoms.

Among these, a structure in which at least one hydrogen in the carbon at the α -position of cycloalkane (in a cycloalkyl group condensed in an aryl ring or a heteroaryl ring, the carbon at the position adjacent to the carbon at the condensation position) is substituted is preferable, a structure in which two hydrogens in the carbon at the α -position are substituted is more preferable, and a structure in which a total of four hydrogens in the two carbons at the α -position are substituted is further preferable. Examples of the substituent include an alkyl (particularly methyl) substituent having 1 to 5 carbon atoms, a halogen (particularly fluorine) substituent, and a deuterium substituent. Particularly preferred is a structure in which a partial structure represented by the following formula (B10) or formula (B11) is bonded to adjacent carbon atoms in an aryl ring or heteroaryl ring.

In the formula, Me represents a methyl group and X represents a bonding position.

In addition, all or a part of the hydrogens in the compound represented by formula (1) or formula (2) may be replaced with deuterium. For example, in the formula (1), ring A, ring B, ring C, ring D (rings A to D are aryl or heteroaryl rings), substituents for rings A to D, and the group X¹～X⁴R (═ aryl, heteroaryl, alkyl), R in N-R¹、R²、Z¹And Z²The hydrogen in (b) may be replaced by deuterium, but among these, there may be mentioned a form in which all or a part of the hydrogen in the aryl or heteroaryl group is replaced by deuterium.

As described above, as X in the formula (1)¹、X²、X³And X⁴R of > N-R and > CR₂R of (a) may be bonded to the a ring, B ring, C ring, and/or D ring by a linking group or a single bond, respectively, but the linking group in this case may be the same as the linking group in which the substituent in the a ring, B ring, C ring, and/or D ring is bonded to the aryl ring or heteroaryl ring. Examples of such a linking group include boron, and for example, in formula (2), the following forms are mentioned.

(1)Z¹And as X¹R of > N-R together via R⁴I.e. B (boron) to bond with the a ring

(2)Z²And as X³R of > N-R together via R⁹I.e. B (boron) to bond with the c ring

(3)Z¹And as X²R of > N-R together via R³I.e. B (boron) to bond with the a ring

(4)Z²And as X⁴R of > N-R together via R⁸I.e., B (boron), to the c-ring.

Examples of structures satisfying any of the above-mentioned (1) to (4) include compounds represented by any of the following formulae (1-X-1), (1-X-2), (1-X-3) and (1-X-4). The formula (1-X-1) satisfies the above (1) and (2), the formula (1-X-2) satisfies the above (1) and (4), the formula (1-X-3) satisfies the above (3) and (2), and the formula (1-X-4) satisfies the above (3) and (4).

Other specific examples of the polycyclic aromatic compound represented by the formula (1) include compounds represented by the following formulae. In the following formulae, "Me" represents a methyl group, "tBu" represents a tert-butyl group, and "D" represents deuterium.

2. Method for producing polycyclic aromatic compound

The polycyclic aromatic compound represented by the formula (1) and preferably the formula (2) can be basically produced as a final product (second reaction) by producing an intermediate by bonding the respective ring structures to each other (first reaction), and then bonding the respective ring structures to each other by a boron atom. In the first Reaction, for example, a nucleophilic substitution Reaction, a general etherification Reaction such as Ullmann Reaction, or a general amination Reaction such as Buchwald-Hartwig Reaction, or a Buchwald-Hartwig Reaction can be used. In the second Reaction, a Tandem Hetero-Friedel-Crafts Reaction (successive aromatic electrophilic substitution Reaction, the same applies hereinafter) can be used. In the following schemes, the symbols in the structural formulae are defined as the same as those in formula (1) or formula (2).

As shown in the following scheme (1), the second reaction is a reaction in which boron atoms bonding respective ring structures are introduced. First, X is converted to X by n-butyllithium, sec-butyllithium, tert-butyllithium or the like¹And X²And X³And X⁴Ortho-metallation of hydrogen atoms in between. Then, boron trichloride, boron tribromide or the like is added to perform metal exchange of lithium-boron, and then a bronsted base such as N, N-diisopropylethylamine or the like is added to perform a tandem boron-hybrid reed-quart reaction, whereby a target product can be obtained. In the second reaction, a Lewis acid such as aluminum trichloride may be added to accelerate the reaction.

Flow (1)

In the process (1), lithium is introduced into a desired position by ortho-metalation, but as in the process (2) described below, a halogen atom (Hal) may be introduced into a position to which lithium is to be introduced in advance, and lithium may be introduced into a desired position by halogen-metal exchange. According to the above method, even when ortho-metalation is not possible due to the influence of a substituent, the target compound can be synthesized and is useful.

Flow (2)

By appropriately selecting the synthesis method and also appropriately selecting the raw materials used, a compound having a substituent at a desired position can be synthesized; x ¹、X²、X³And X⁴Independently of each other > O, > N-R, > CR₂Polycyclic aromatic compounds > S or > Se.

Further, the site where the tandem borohydrid-quart reaction occurs may be different depending on, for example, the rotation of the amino group in the intermediate, and therefore, a by-product may be formed. In this case, the target polycyclic aromatic compound can be isolated from the mixture thereof by chromatography, recrystallization or the like.

Examples of the ortho-metallation reagent used in the above-mentioned process include: alkyllithium such as methyllithium, n-butyllithium, sec-butyllithium and tert-butyllithium, and organic basic compounds such as lithium diisopropylamide, lithium tetramethylpiperidide, lithium hexamethyldisilazide and potassium hexamethyldisilazide.

Examples of the metal-boron metal exchange reagent used in the above-mentioned process include: boron halides such as boron trifluoride, trichloride, tribromide and triiodide; CIPN (NEt)₂)₂And the like, boron aminated halides; alkoxylates of boron; boron aryloxides, and the like.

Examples of the bransted base used in the above-mentioned scheme include: n, N-diisopropylethylamine, triethylamine, 2,2,6, 6-tetramethylpiperidine, 1,2,2,6, 6-pentamethylpiperidine, N-dimethylaniline, N-dimethyltoluidine, 2, 6-lutidine, sodium tetraphenylborate, potassium tetraphenylborate, triphenylborane, tetraphenylsilane, Ar, N-diisopropylethylamine, N-tetramethylpiperidine, N-dimethyltoluidine, N-dimethylpyridine, N-tetramethylpiperidine, N-dimethylpiperidine, N-dimethylpiperidine ₄BNa、Ar₄BK、Ar₃B、Ar₄Si (Ar is an aryl group such as phenyl) and the like.

As lewis acids used in the above-mentioned schemes, there can be mentioned: AlCl₃、AlBr₃、AlF₃、BF₃·OEt₂、BCl₃、BBr₃、GaCl₃、GaBr₃、InCl₃、InBr₃、In(OTf)₃、SnCl₄、SnBr₄、AgOTf、ScCl₃、Sc(OTf)₃、ZnCl₂、ZnBr₂、Zn(OTf)₂、MgCl₂、MgBr₂、Mg(OTf)₂、LiOTf、NaOTf、KOTf、Me₃SiOTf、Cu(OTf)₂、CuCl₂、YCl₃、Y(OTf)₃、TiCl₄、TiBr₄、ZrCl₄、ZrBr₄、FeCl₃、FeBr₃、CoCl₃、CoBr₃And the like.

In the scheme, in order to promote the tandem heterolydrol-quart reaction, a bransted base or a lewis acid may also be used. Among them, in the case of using a boron halide such as boron trifluoride, trichloride, tribromide, triiodide, etc., since an acid such as hydrogen fluoride, hydrogen chloride, hydrogen bromide, hydrogen iodide is generated as the aromatic electrophilic substitution reaction proceeds, it is effective to use a bronsted base which captures the acid. On the other hand, in the case of using a boron amide halide or a boron alkoxide, since an amine or an alcohol is generated as the aromatic electrophilic substitution reaction proceeds, it is not necessary to use a bronsted base in many cases, but since the ability to remove an amino group or an alkoxy group is low, it is effective to use a lewis acid for accelerating the removal.

The polycyclic aromatic compound represented by the formula (1) having a cyano group or a halogen in the structure can be synthesized in the same manner as described above by using a raw material having a desired site subjected to cyanation, halogenation or deuteration. Further, a compound in which at least a part of hydrogen atoms is replaced with deuterium can be synthesized in the same manner as described above by using a raw material in which a desired site is deuterated.

3. Organic device

The polycyclic aromatic compound of the present invention is useful as a material for organic devices. Examples of the organic device include an organic electroluminescent element, an organic field effect transistor, and an organic thin film solar cell.

3-1. organic electroluminescent element

The polycyclic aromatic compound of the present invention is useful, for example, as a material for an organic electroluminescent element. Hereinafter, the organic EL device of the present embodiment will be described in detail with reference to the drawings. Fig. 1 is a schematic sectional view showing an organic EL element according to the present embodiment.

< Structure of organic electroluminescent element >

The organic electroluminescent element 100 shown in fig. 1 includes: the light-emitting device comprises a substrate 101, an anode 102 disposed on the substrate 101, a hole injection layer 103 disposed on the anode 102, a hole transport layer 104 disposed on the hole injection layer 103, a light-emitting layer 105 disposed on the hole transport layer 104, an electron transport layer 106 disposed on the light-emitting layer 105, an electron injection layer 107 disposed on the electron transport layer 106, and a cathode 108 disposed on the electron injection layer 107.

In addition, the organic electroluminescent element 100 may have a configuration in which the order of production is reversed, for example, the configuration may include: the organic light emitting diode comprises a substrate 101, a cathode 108 arranged on the substrate 101, an electron injection layer 107 arranged on the cathode 108, an electron transport layer 106 arranged on the electron injection layer 107, a light emitting layer 105 arranged on the electron transport layer 106, a hole transport layer 104 arranged on the light emitting layer 105, a hole injection layer 103 arranged on the hole transport layer 104, and an anode 102 arranged on the hole injection layer 103.

All of the layers are not indispensable, and the minimum constituent unit is constituted by the anode 102, the light-emitting layer 105, and the cathode 108, and the hole injection layer 103, the hole transport layer 104, the electron transport layer 106, and the electron injection layer 107 are layers that can be arbitrarily provided. In addition, each of the layers may include a single layer, or may include a plurality of layers.

As the form of the layer constituting the organic electroluminescent element, in addition to the form of the constitution of "substrate/anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode", there may be mentioned "substrate/anode/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode", "substrate/anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/cathode"), The structural forms of "substrate/anode/light-emitting layer/electron transport layer/electron injection layer/cathode", "substrate/anode/hole transport layer/light-emitting layer/electron transport layer/cathode", "substrate/anode/hole injection layer/light-emitting layer/electron injection layer/cathode", "substrate/anode/hole injection layer/light-emitting layer/electron transport layer/cathode", "substrate/anode/light-emitting layer/electron injection layer/cathode".

< substrate in organic electroluminescent element >

The substrate 101 is a support of the organic electroluminescent element 100, and quartz, glass, metal, plastic, or the like is generally used. The substrate 101 is formed in a plate shape, a film shape, or a sheet shape according to the purpose, and for example, a glass plate, a metal foil, a plastic film, a plastic sheet, or the like can be used. Among them, a glass plate and a plate made of a transparent synthetic resin such as polyester, polymethacrylate, polycarbonate, polysulfone are preferable. In the case of a glass substrate, soda-lime glass, alkali-free glass, or the like can be used, and the thickness is sufficient to maintain mechanical strength, and therefore, for example, it is sufficient if the thickness is 0.2mm or more. The upper limit of the thickness is, for example, 2mm or less, preferably 1mm or less. As for the material of the glass, the less the ion eluted from the glass, the better, so it is preferably alkali-free glass, because SiO is applied₂Etc. soda lime glass for barrier coating (barrier coat) is also commercially available, and therefore the soda lime glass can be used. In addition, in order to improve the gas barrier property, a gas barrier film such as a fine silicon oxide film may be provided on at least one surface of the substrate 101, and in particular, when a synthetic resin plate, film or sheet having low gas barrier property is used as the substrate 101, it is preferable to provide a gas barrier film.

< Anode in organic electroluminescent element >

The anode 102 functions to inject holes into the light-emitting layer 105. Further, when the hole injection layer 103 and/or the hole transport layer 104 are provided between the anode 102 and the light-emitting layer 105, holes are injected into the light-emitting layer 105 via the layers.

Examples of the material for forming the anode 102 include inorganic compounds and organic compounds. Examples of the inorganic compound include: metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (Indium Oxide, Tin Oxide, Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), etc.), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass, or nesa glass. Examples of the organic compound include: polythiophene such as poly (3-methylthiophene), and conductive polymers such as polypyrrole and polyaniline. Further, it can be suitably selected from substances used as an anode of an organic electroluminescence element.

The resistance of the transparent electrode is not limited as long as a sufficient current can be supplied to light emission of the light-emitting element, but is preferably low in terms of power consumption of the light-emitting element. For example, an ITO substrate of 300 Ω/γ or less functions as an element electrode, but a substrate of about 10 Ω/γ may be provided at present, and therefore, a low-resistance product of, for example, 100 Ω/γ to 5 Ω/γ, preferably 50 Ω/γ to 5 Ω/γ is particularly preferably used. The thickness of ITO can be arbitrarily selected depending on the resistance value, but is usually used in many cases between 50nm and 300 nm.

< hole injection layer and hole transport layer in organic electroluminescent element >

The hole injection layer 103 functions to efficiently inject holes transferred from the anode 102 into the light-emitting layer 105 or the hole transport layer 104. The hole transport layer 104 functions to efficiently transport holes injected from the anode 102 or holes injected from the anode 102 through the hole injection layer 103 to the light-emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are formed by laminating and mixing one or more kinds of hole injection and transport materials, or are formed by mixing a hole injection and transport material and a polymer binder. Further, an inorganic salt such as iron (III) chloride may be added to the hole injection/transport material to form a layer.

As the hole injecting/transporting material, it is necessary to efficiently inject and transport holes from the positive electrode between the electrodes to which the electric field is supplied, and it is desirable that the injected holes be efficiently transported with high hole injection efficiency. Therefore, a substance having a small ionization potential, a large hole mobility, and excellent stability, and in which impurities serving as traps are not easily generated during production and use, is preferable.

As the material for forming the hole injection layer 103 and the hole transport layer 104, any compound can be selected from compounds conventionally used as charge transport materials for holes in photoconductive materials, p-type semiconductors, and conventional compounds used in hole injection layers and hole transport layers of organic electroluminescent devices.

Specific examples of the compound include carbazole derivatives (e.g., N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis (N-arylcarbazole) and bis (N-alkylcarbazole), triarylamine derivatives (e.g., polymers having an aromatic tertiary amino group in the main chain or side chain, 1-bis (4-di-p-tolylaminophenyl) cyclohexane, N ' -diphenyl-N, N ' -di (3-methylphenyl) -4,4' -diaminobiphenyl, N ' -diphenyl-N, N ' -dinaphthyl-4, 4' -diaminobiphenyl, N ' -diphenyl-N, N ' -di (3-methylphenyl) -4,4' -diphenyl-1, 1' -diamine, N ' -dinaphthyl-N, N ' -diphenyl-4, 4' -diphenyl-1, 1' -diamine, N⁴,N⁴' -Diphenyl-N⁴,N⁴'-bis (9-phenyl-9H-carbazol-3-yl) - [1,1' -biphenyl]4,4' -diamine, N⁴,N⁴,N⁴',N⁴'-tetrakis ([1,1' -biphenyl)]-4-yl) - [1,1' -biphenyl]Triphenylamine derivatives such as-4, 4 '-diamine, 4',4 ″ -tris (3-methylphenyl (phenyl) amino) triphenylamine, starburst amine derivatives, and the like), stilbene derivatives, phthalocyanine derivatives (metal-free, copper phthalocyanine, and the like), pyrazoline derivatives, hydrazone-based compounds, benzofuran derivatives or thiophene derivatives, oxadiazole derivatives, quinoxaline derivatives (for example, 1,4,5,8,9, 12-hexaazatriphenylene-2, 3,6,7,10, 11-hexacarbonitrile, and the like), heterocyclic compounds such as porphyrin derivatives, polysilanes, and the like. In the polymer system, polycarbonate or styrene derivative, polyvinylcarbazole, polysilane, or the like having the monomer in the side chain is preferable, but there is no particular limitation as long as it is a compound which forms a thin film necessary for manufacturing a light-emitting element, and which can inject holes from an anode and can further transport holes.

Further, it is also known that the conductivity of an organic semiconductor is strongly affected by doping. Such an organic semiconductor matrix material contains a compound having a good electron donating property or a compound having a good electron accepting property. For the doping of electron-donating substances, strong electron acceptors such as Tetracyanoquinodimethane (TCNQ) or 2,3,5, 6-tetrafluorotetracyanoquinodimethane (2,3,5, 6-tetrafluorolotetracynano-1, 4-benzoquinodimethane, F4TCNQ) are known (see, for example, documents "m. faefer, a. baie, t. friez, k. rio (m. pfeiffer, a. beyer, t.fritz, k.leo)," applied physics promo (appl. phys. lett.), (73), (22), 3202. quiz 3204(1998) "and documents" j. buherervz, m. faeffer, t. friez, k. litt.), "applied physics promo (pfeir, pf. pfeir.)," applied physics, k. floitz, t. leuz) ", and documents" j. beherervz, m. faffeiz, m. mez, t. bevetz., "applied physics. They generate so-called holes by an electron transfer process in an electron-donating base substance (hole-transporting substance). The conductivity of the base material varies considerably depending on the number and mobility of holes. As a matrix material having a hole transporting property, for example, a benzidine derivative (N, N ' -Bis (3-methylphenyl) -N, N ' -Bis (phenyl) benzidine, TPD, etc.) or a starburst amine derivative (4,4',4 ″ -Tris (N, N-diphenylamino) triphenylamine, TDATA, etc.), or a specific metal phthalocyanine (particularly zinc phthalocyanine (ZnPc), etc.) is known (japanese patent laid-open No. 2005-167175). As the hole injecting/transporting material, a conductive polymer known as poly (3,4-ethylenedioxythiophene)/poly (styrenesulfonate) (poly (3,4-ethylenedioxythiophene)/poly (phenylenesulfonate), PEDOT/PSS) shown in examples can be used.

Crosslinkable polymer material: a compound represented by the formula (XLP-1)

The hole injection layer and the hole transport layer preferably contain a compound represented by formula (XLP-1). Further, the compound represented by the formula (XLP-1) may be contained in another organic layer in the organic electroluminescent element. In particular, when the organic layer is formed by a wet film formation method using the composition for forming an organic layer, the composition for forming an organic layer preferably contains a compound represented by formula (XLP-1).

In the formula (XLP-1),

MUx is a divalent group obtained by removing any two hydrogens of the MU or the aromatic compound having a crosslinkable substituent (PG), and ECx is a monovalent group obtained by removing any one hydrogen of the EC or the aromatic compound having a crosslinkable substituent (PG), wherein the content of the monovalent and divalent aromatic compounds having a crosslinkable substituent (PG) is 0.1-80 wt% in the molecule, and k is an integer of 2-50000.

More specifically, the present invention is to provide a novel,

MUx wherein any two hydrogens of the aromatic compound having a crosslinkable substituent (PG) are removed are each independently an arylene group, a heteroarylene group, a diarylenearylamino group, a diarylenearylboronyl group, a oxaboronyl-hexenediyl group, or an oxaboronyl-hexenediyl group, wherein at least one hydrogen of these divalent groups is substituted with the crosslinkable substituent (PG), and wherein at least one hydrogen of these divalent groups is further substituted with one or more substituents selected from the group consisting of an aryl group, a heteroaryl group, a diarylamino group, an alkyl group, and a cycloalkyl group. When two or more crosslinkable substituents (PG) are present in MUx, they may be the same or different, and are preferably the same.

The monovalent groups obtained by removing any hydrogen of the aromatic compound having the crosslinkable substituent (PG) in ECx are each independently an aryl group, a heteroaryl group, a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, or an aryloxy group, at least one hydrogen of these monovalent groups is substituted with the crosslinkable substituent (PG), and at least one hydrogen of these monovalent groups may be further substituted with one or more substituents selected from the group consisting of an aryl group, a heteroaryl group, a diarylamino group, an alkyl group, and a cycloalkyl group. When two or more crosslinkable substituents (PG) are present in ECx, they may be the same or different, and are preferably the same.

The content of the divalent group obtained by removing any two hydrogens of the aromatic compound having the crosslinkable substituent (PG) and the monovalent group obtained by removing any one hydrogen of the aromatic compound is 0.1 to 80 wt%, preferably 0.5 to 50 wt%, more preferably 1 to 20 wt% in the molecule.

k is an integer of 2 to 50000, preferably an integer of 20 to 50000, and more preferably an integer of 100 to 50000. In the case where the k Mux s contain two or more divalent groups, these groups may be randomly bonded, and the same divalent group may be a block, but the latter is preferable.

Examples of the crosslinkable substituent (PG) include monovalent groups formed by bonding L in a divalent partial structure to a monovalent crosslinkable partial structure represented by the following formulae (PG-1) to (PG-18).

In the formulae (PG-1) to (PG-18), R^PGRepresents a methylene group, an oxygen atom or a sulfur atom, n^PGRepresents an integer of 0 to 5, in the presence of a plurality of R^PGIn the case where n is present in plural, they may be the same or different^PGWherein G represents a bonding position (bonding position to L), and the crosslinking group represented by the formula may have a substituent.

As L in the divalent partial structure in the crosslinkable substituent (PG), there can be mentioned: a single bond, -O-, > C- ═ O, -O-C (-O) -, C1-12 alkylene, C1-12 oxyalkylene and C1-12 polyoxyalkylene. The crosslinkable substituent (PG) is preferably represented by the formula (PG-1), the formula (PG-2), the formula (PG-3), the formula (PG-9), the formula (PG-10) or the formula (PG-18), more preferably represented by the formula (PG-1), the formula (PG-3) or the formula (PG-18).

When a plurality of crosslinkable substituents (PG) are present in the formula (XLP-1), they may be the same or different.

Examples of the divalent group obtained by removing any two hydrogens of the aromatic compound having the crosslinkable substituent (PG) include the following divalent groups.

< light-emitting layer in organic electroluminescent element >

The light-emitting layer 105 emits light by recombination of holes injected from the anode 102 and electrons injected from the cathode 108 between the electrodes to which an electric field is supplied. The material for forming the light-emitting layer 105 may be a compound (light-emitting compound) which emits light by being excited by recombination of holes and electrons, and is preferably a compound which can be formed into a stable thin film shape and which exhibits strong light emission (fluorescence) efficiency in a solid state. In the present invention, it is preferable to use a polycyclic aromatic compound represented by the formula (1) as a material for the light-emitting layer.

The light-emitting layer may be a single layer or may include a plurality of layers, and each of the layers is formed of a material (host material or dopant material) for the light-emitting layer. The host material and the dopant material may be one kind or a combination of two or more kinds, respectively. The dopant material may be contained within the entire host material, or may be contained within portions of the host material, either. The doping method may be a co-evaporation method with the host material, a simultaneous evaporation method after mixing with the host material in advance, or a wet film-forming method after mixing with the host material in advance together with an organic solvent.

The amount of the host material to be used differs depending on the type of the host material, and may be determined in accordance with the characteristics of the host material. The amount of the host material used is preferably 50 to 99.999 mass%, more preferably 80 to 99.95 mass%, and still more preferably 90 to 99.9 mass% of the total amount of the material for the light-emitting layer.

The amount of the dopant material used differs depending on the type of the dopant material, and may be determined by matching the characteristics of the dopant material. The amount of the dopant used is preferably 0.001 to 50% by mass, more preferably 0.05 to 20% by mass, and still more preferably 0.1 to 10% by mass, based on the total amount of the material for the light-emitting layer. In the above range, for example, concentration quenching is preferably prevented.

On the other hand, in the organic electroluminescent element using the thermally activated delayed fluorescence dopant material, the amount of the dopant material used is preferably low in terms of preventing the concentration quenching phenomenon, but is preferably high in terms of the efficiency of the thermally activated delayed fluorescence mechanism. Further, in the organic electroluminescent element using the thermally activated delayed fluorescence auxiliary dopant material, it is preferable that the amount of the dopant material (emission dopant) used is lower than the amount of the auxiliary dopant material in terms of the efficiency of the thermally activated delayed fluorescence mechanism of the auxiliary dopant material.

When the auxiliary dopant material is used, the amounts of the host material, the auxiliary dopant material, and the dopant material used are 40 to 99.999 mass%, 59 to 1 mass%, and 20 to 0.001 mass%, preferably 60 to 99.99 mass%, 39 to 5 mass%, and 10 to 0.01 mass%, more preferably 70 to 99.95 mass%, 29 to 10 mass%, and 5 to 0.05 mass%, respectively, of the entire light-emitting layer material. The compounds of the invention and their polymeric compounds can also be used as auxiliary dopant materials.

[ host Material ]

Examples of the host material include condensed ring derivatives such as anthracene and pyrene, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, fluorene derivatives, and benzofluorene derivatives, which are known from the past as a light-emitting body.

From the viewpoint of not inhibiting but promoting the generation of TADF in the light-emitting layer, the T1 energy of the host material is preferably higher than the T1 energy of the dopant or the auxiliary dopant having the highest T1 energy in the light-emitting layer, and specifically, the T1 energy of the host is preferably 0.01eV or more, more preferably 0.03eV or more, and still more preferably 0.1eV or more. In addition, a compound having TADF activity may also be used in the host material.

Examples of the host material include compounds represented by the following formula (3), the following formula (4), and the following formula (5).

In the formula (3), L¹The arylene group has 6 to 24 carbon atoms, preferably 6 to 16 carbon atoms, more preferably 6 to 12 carbon atoms, particularly preferably 6 to 10 carbon atoms, and specifically, the following may be mentioned: a divalent group such as a benzene ring, a biphenyl ring, a naphthalene ring, a terphenyl ring, an acenaphthene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, a triphenylene ring, a pyrene ring, a tetracene ring, a perylene ring, and a pentacene ring.

In the formula (4), L²And L³Each independently an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 30 carbon atoms. The aryl group is preferably an aryl group having 6 to 24 carbon atoms, more preferably an aryl group having 6 to 16 carbon atoms, further preferably an aryl group having 6 to 12 carbon atoms, particularly preferably an aryl group having 6 to 10 carbon atoms, and specifically, there can be mentioned: a monovalent group such as a benzene ring, a biphenyl ring, a naphthalene ring, a terphenyl ring, an acenaphthene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, a triphenylene ring, a pyrene ring, a tetracene ring, a perylene ring, and a pentacene ring. The heteroaryl group is preferably a heteroaryl group having 2 to 25 carbon atoms, more preferably a heteroaryl group having 2 to 20 carbon atoms, still more preferably a heteroaryl group having 2 to 15 carbon atoms, particularly preferably a heteroaryl group having 2 to 10 carbon atoms, and specifically, there can be mentioned: pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, oxadiazole ring, thiadiazole ring, triazole ring, tetrazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyridazine ring, pyrazine ring, triazine ring, indole ring, isoindole ring, 1H-indazole ring, benzimidazole ring, benzoxazole ring, benzothiazole ring, 1H-benzotriazole ring, quinoline ring, isoquinoline ring, cinnoline ring, quinazoline ring, quinoxaline ring, oxazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, acridine ring, phenoxathiin ring, phenoxazine ring, phenothiazine ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, indole ring, imidazole ring, oxadiazole ring, thiadiazole ring, triazole ring, 1H-indazole ring, quinoline ring, quinazoline A thiophene ring, a dibenzothiophene ring, a furazan ring, an oxadiazole ring, a thianthrene ring, and the like.

In the formula (5), L⁴、L⁵And L⁶Each independently an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 30 carbon atoms. The aryl group is preferably an aryl group having 6 to 24 carbon atoms, more preferably an aryl group having 6 to 16 carbon atoms, further preferably an aryl group having 6 to 12 carbon atoms, particularly preferably an aryl group having 6 to 10 carbon atoms, and specifically, there can be mentioned: a monovalent group such as a benzene ring, a biphenyl ring, a naphthalene ring, a terphenyl ring, an acenaphthene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, a triphenylene ring, a pyrene ring, a tetracene ring, a perylene ring, and a pentacene ring. The heteroaryl group is preferably a heteroaryl group having 2 to 25 carbon atoms, more preferably a heteroaryl group having 2 to 20 carbon atoms, still more preferably a heteroaryl group having 2 to 15 carbon atoms, particularly preferably a heteroaryl group having 2 to 10 carbon atoms, and specifically, there can be mentioned: a monovalent group such as a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring, a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, an isoindole ring, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a 1H-benzotriazole ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinazoline ring, a quinoxaline ring, a oxazine ring, a naphthyridine ring, a purine ring, a pteridine ring, a carbazole ring, an acridine ring, a phenoxathiin ring, a phenoxazine ring, a phenothiazine ring, an indolizine ring, a furan ring, a benzofuran ring, an isobenzofuran ring, a dibenzofuran ring, a thiophene ring, a benzothiophene ring, a furazan ring, an oxadiazole ring, and a thianthracene ring.

At least one hydrogen in the compound represented by formula (3), formula (4) or formula (5) may be substituted by an alkyl group having 1 to 6 carbon atoms, a cyano group, a halogen or deuterium.

As the host compound, a compound having at least one structure selected from the group of partial structures (H-a) represented by the following formula is preferably used. The compound may be a compound represented by formula (3), formula (4) or formula (5), or may be another compound. At least one hydrogen atom in each structure of the group of partial structures (H-A) may be substituted by any one of the group of partial structures (H-A) or the group of partial structures (H-B), and at least one hydrogen atom in these structures may be substituted by deuterium, halogen, cyano, alkyl having 1 to 4 carbon atoms (e.g., methyl or tert-butyl), trimethylsilyl or phenyl.

(H-A)

(H-B)

The main compound is preferably a compound represented by any one of the structural formulae listed below, and among these compounds, a compound having one to three structures selected from the group consisting of the partial structure (H-a) and one structure selected from the group consisting of the partial structure (H-B) is more preferred, and a compound having a carbazolyl group as the partial structure (H-a) is even more preferred, and a compound represented by the following formula (3-201), formula (3-202), formula (3-203), formula (3-204), formula (3-212), formula (3-221), formula (3-222), formula (3-261) or formula (3-262) is particularly preferred. In the following structural formulae, at least one hydrogen may be substituted by a halogen, a cyano group, an alkyl group having 1 to 4 carbon atoms (for example, a methyl group or a tert-butyl group), a phenyl group, a naphthyl group, or the like. In the following formulae, Me represents a methyl group.

As the host material, the following polymer host material can also be used.

In the formula (SPH-1), the MUs are independently at least one selected from the group consisting of divalent groups of compounds represented by the formulae (B-1) to (B-4), two hydrogens of the MUs are substituted with EC or MU, EC is independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino or aryloxy, at least one hydrogen of them may be further substituted with aryl, heteroaryl or diarylamino, and k is an integer of 2 to 50000. k is preferably an integer of 100 to 40000, more preferably an integer of 500 to 25000.

The compounds represented by the formulae (B-1) to (B-4) are the following compounds.

In the formulae (B-1) to (B-4), Ar is each independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino or aryloxy, at least one hydrogen of which may in turn be substituted by aryl, heteroaryl or diarylamino, adjacent groups in Ar may be bonded to each other and together with the parent skeleton of the anthracene, pyrene, fluorene or carbazole rings, respectively, form an aryl or heteroaryl ring, and at least one hydrogen of the formed rings may be substituted by aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino or aryloxy. Specific descriptions of the groups may be cited as in the polycyclic aromatic compound of the formula (1) or the formula (2). In each formula, n is an integer of 1 to 6, preferably an integer of 1 to 4, more preferably an integer of 1 to 2, and particularly preferably 1.

Specific examples of "Ar" in the formulae (B-1) to (B-4) include monovalent groups represented by the following structural formulae and groups having combinations of the following structures.

At least one hydrogen in the compounds represented by the formulae (B-1) to (B-4) may be substituted by a group represented by the formula (FG-1) described later, a group represented by the formula (FG-2) described later, or an alkyl group having 1 to 24 carbon atoms, a halogen or deuterium, and further, any-CH in the alkyl group₂Can be composed of-O-or-Si (CH)₃)₂-substituted, except for-CH in the alkyl group directly bonded to the compound represented by the formulae (B-1) to (B-4)₂Any other than-CH₂The alkyl group may be substituted with an arylene group having 6 to 24 carbon atoms, and any hydrogen in the alkyl group may be substituted with fluorine.

At least one hydrogen in EC in the formula (SPH-1) may be substituted by a group represented by the following formula (FG-1), a group represented by the following formula (FG-2), an alkyl group having 1 to 24 carbon atoms, a halogen, or deuterium, and further, any-CH in the alkyl group₂Can be composed of-O-or-Si (CH)₃)₂-substitution in the alkyl group except-CH directly bonded to EC in formula (B-6)₂Any other than-CH₂The alkyl group may be substituted with an arylene group having 6 to 24 carbon atoms, and any hydrogen in the alkyl group may be substituted with fluorine.

(in the formula (FG-1),

r is independently fluorine, trimethylsilyl, trifluoromethyl, C1-C24 alkyl or C3-C24 cycloalkyl, and any-CH in the alkyl ₂-CH which may be substituted by-O-, other than the one directly bonded to the phenyl or phenylene group in said alkyl group₂Any other than-CH₂May be substituted with an arylene group having 6 to 24 carbon atoms, at least one hydrogen in the cycloalkyl group may be substituted with an alkyl group having 1 to 24 carbon atoms or an aryl group having 6 to 12 carbon atoms,

when two adjacent R's are alkyl or cycloalkyl, they may be bonded to form a ring,

m is independently an integer of 0 to 4, n is an integer of 0 to 5, p is an integer of 1 to 5, and represents a bonding position)

(in the formula (FG-2),

r is independently fluorine, trimethylsilyl, trifluoromethyl, C1-24 alkyl, C3-24 cycloalkyl or C6-12 aryl, and any-CH in the alkyl₂-CH which may be substituted by-O-, other than the one directly bonded to the phenyl or phenylene group in said alkyl group₂Any other than-CH₂May be substituted with an arylene group having 6 to 24 carbon atoms, at least one hydrogen in the cycloalkyl group may be substituted with an alkyl group having 1 to 24 carbon atoms or an aryl group having 6 to 12 carbon atoms, at least one hydrogen in the aryl group may be substituted with an alkyl group having 1 to 24 carbon atoms,

m is an integer of 0 to 4, n is an integer of 0 to 5 independently, and represents a bonding position)

Examples of the MU include: a divalent group represented by the following formulae (MU-1-1) to (MU-1-12), the following formulae (MU-2-1) to (MU-2-202), the following formulae (MU-3-1) to (MU-3-201), and the following formulae (MU-4-1) to (MU-4-122). Examples of EC include groups represented by the following formulae (EC-1) to (EC-29). In these, MU is bonded to MU or EC at one site, and EC is bonded to MU at one site.

Further, from the viewpoint of charge transport, the compound represented by the formula (SPH-1) preferably has at least one divalent group represented by the formula (B-5-X1) in the molecule, and more preferably has 10% or more of the divalent group represented by the formula (B-5-X1) relative to the molecular weight of the compound represented by the formula (SPH-1). Here, the divalent group represented by the formula (B-5-X1) is bonded to MU or EC at a position X.

From the viewpoint of solubility and coating film forming properties, the compound represented by the formula (SPH-1) preferably has an alkyl group having 1 to 24 carbon atoms in 10 to 100% of MUs of the total number of MUs (n) in the molecule, more preferably has an alkyl group having 1 to 18 carbon atoms (branched alkyl group having 3 to 18 carbon atoms) in 30 to 100% of MUs of the total number of MUs (n) in the molecule, and still more preferably has an alkyl group having 1 to 12 carbon atoms (branched alkyl group having 3 to 12 carbon atoms) in 50 to 100% of MUs of the total number of MUs (n) in the molecule. On the other hand, from the viewpoint of in-plane orientation and charge transport, it is preferable that 10% to 100% of the MUs of the total number of MUs (n) in a molecule have an alkyl group having 7 to 24 carbon atoms, and more preferably 30% to 100% of the MUs of the total number of MUs (n) in a molecule have an alkyl group having 7 to 24 carbon atoms (branched alkyl group having 7 to 24 carbon atoms).

TADF Material (auxiliary dopant)

The light-emitting layer preferably contains a TADF material.

In the present specification, the TADF material refers to a material of the "thermally active retardation phosphor". In the "thermally active delayed phosphor", the energy difference between the excited singlet state and the excited triplet state is reduced, whereby reverse energy transfer from the self-excited triplet state to the excited singlet state, which is generally low in transition probability, is efficiently generated, and light emission from the singlet state (thermally active delayed fluorescence, TADF) is exhibited. In general fluorescence emission, 75% of triplet excitons generated by current excitation pass through a thermal deactivation path, and thus cannot be extracted as fluorescence. On the other hand, in TADF, all excitons can be used for fluorescence emission, and a highly efficient organic EL device can be realized.

The TADF material is preferably a donor-acceptor type TADF compound (a TADF compound of D-a type) designed to localize HOMO and LUMO within molecules using an electron donating substituent called a donor and an electron accepting substituent called an acceptor to produce efficient reverse intercross crossing.

In the present specification, the term "electron-donating substituent" (donor) refers to a substituent and a partial structure that are localized in the HOMO orbital of the TADF compound molecule, and the term "electron-accepting substituent" (acceptor) refers to a substituent and a partial structure that are localized in the LUMO orbital of the TADF compound molecule.

In general, TADF compounds using a donor or acceptor have a large Spin Orbit Coupling (SOC) and a small exchange interaction between HOMO and LUMO, Δ E, due to structural reasons_S1T1Small and therefore very fast reverse inter-system crossing speeds can be achieved. On the other hand, a TADF compound using a donor or an acceptor has a large structural relaxation in an excited state (in a molecule, since a stable structure is different between a ground state and an excited state, when a transition from the ground state to the excited state is generated by an external stimulus, the structure is changed to a stable structure in the excited state thereafter), and a broad emission spectrum is provided, and therefore, when it is used as a light-emitting material, there is a possibility that color purity is lowered.

However, by using the polycyclic aromatic compound of the present invention together, the polycyclic aromatic compound of the present invention functions as an emitting dopant and the TADF material functions as an auxiliary dopant, and thus high color purity can be provided. The TADF material may be any material as long as it has an emission spectrum at least partially overlapping with the absorption spectrum of the polycyclic aromatic compound of the present invention. The polycyclic aromatic compound of the present invention and the TADF material may be contained in the same layer, or may be contained in adjacent layers.

Examples of the TADF material that can be used for such a purpose include a compound represented by the following formula (H7) and a compound having the following formula (H7) as a partial structure.

ED-Ln-EA (H7)

In the formula (H7), ED is an electron donating group, Ln is a linking group, EA is an electronThe lowest excited singlet energy level (E) of the acceptor group, the compound represented by the formula (H7)_S1) With the lowest excited triplet energy level (E)_T1) Energy difference (Δ E)_S1T1) Is below 0.2eV (Hiroki UOyama, Xinzhijian (Kenichi Goushi), Zhijin Katsuyuki Shizu, wild Haozi (Hiroko Nomura), Chihaya Adachi, Nature (Nature), 492,234-238 (2012)). Energy difference (Δ E)_S1T1) Preferably 0.15eV or less, more preferably 0.10eV or less, and still more preferably 0.08eV or less.

As electron donating groups (donor structures) and electron accepting groups (acceptor structures) used in TADF Materials, for example, the structures described in Chemistry of Materials (2017, 29, 1946-1963) can be used. The ED may contain sp³More specifically, the nitrogen functional group includes carbazole, dimethylcarbazole, di-t-butylcarbazole, dimethoxycarbazole, tetramethylcarbazole, benzofluorocarbazole, benzothiophenocarbazole, phenylindolinocarbazole, phenylbicarbazole, bicarbazole, tercarbazole (tercarbazole), diphenylcarbazolylamine, tetraphenylcarbazolylamine, phenoxazine, dihydrophenazine, phenothiazine, dimethylacridine, diphenylamine, bis (4- (t-butyl) phenyl) amine, N '- (4- (diphenylamino) phenyl) -N' - (4- (diphenylamino) phenyl) N-carbazolyl diamine ⁴,N⁴A group derived from diphenylbenzene-1, 4-diamine, dimethylatetraphenyldihydroacridine diamine, tetramethyl-dihydro-indenoacridine, diphenyl-dihydrodibenzoazasilaline, or the like. Further, the EA includes, for example, an sp-containing compound²Nitrogen aromatic ring, CN-substituted aromatic ring, ketone-containing ring and cyano group, and more specifically, there may be mentioned sulfonyldiphenyl, benzophenone, phenylenebis (benzophenone), benzonitrile, isonicotinonitrile, phthalonitrile, isophthalonitrile, terephthalonitrile, triazole, oxazole, thiadiazole, benzothiazole, benzobis (thiazole), benzoxazole, benzobis (oxazole), quinoline, benzimidazole, dibenzoquinoxaline, heptaazaphenalene, thioxanthone dioxide, dimethylanthrone, anthracenedione, pyridine, cycloheptylpyridine, benzenetricarbonitrile, fluorenedicarbonitrile, pyrazinedicarbonitrile, pyridinedicarbonitrile, dibenzoquinoxaline dicarbonitrile, dibenzoquinonedicarbonitrile, quinophthalone, phthalone, and phthalone,Pyrimidine, phenylpyrimidine, methylpyrimidine, triazine, triphenyltriazine, bis (phenylsulfonyl) benzene, dimethylthioxanthone dioxide, thianthrene tetraoxide, tris (dimethylphenyl) borane, and the like. Examples of Ln include a single bond and an arylene group, and more specifically, a phenylene group, a biphenylene group, a naphthylene group, and the like. In either structure, hydrogen may be substituted with alkyl, cycloalkyl, and aryl groups. Particularly preferred are compounds having at least one member selected from the group consisting of carbazole, phenoxazine, acridine, triazine, pyrimidine, pyrazine, thioxanthone, benzonitrile, phthalonitrile, isophthalonitrile, diphenylsulfone, triazole, oxadiazole, thiadiazole, and benzophenone as a partial structure.

In the formula (H7), Ln of the linking group functions as a spacer structure that separates a partial structure of a donor from a partial structure of a receptor.

More specifically, the compound represented by the formula (H7) may be any compound represented by any one of the formulae (H7-1), (H7-2) and (H7-3).

In the formulae (H7-1), (H7-2) and (H7-3),

m is each independently a single bond, -O-, > N-Ar or > C (-Ar)₂From the viewpoint of the depth of the HOMO of the partial structure to be formed and the heights of the lowest excited singlet level and the lowest excited triplet level, a single bond, -O-, or > N-Ar is preferable,

j is a linking group corresponding to Ln in the formula (H7), each independently is an arylene group having 6 to 18 carbon atoms, and is preferably an arylene group having 6 to 12 carbon atoms, more specifically, a phenylene group, a methylphenylene group, and a dimethylphenylene group,

q is independently ═ C (-H) -or ═ N-, and in terms of the shallowness of the LUMO of the partial structure formed and the heights of the lowest excited singlet level and the lowest excited triplet level, it is preferably ═ N-,

ar is independently hydrogen, an aryl group having 6 to 24 carbon atoms, a heteroaryl group having 2 to 24 carbon atoms, an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 18 carbon atoms, and in terms of the depth of the HOMO of the partial structure formed and the height of the lowest excited singlet level and the lowest excited triplet level, the preferred is hydrogen, an aryl group having 6 to 12 carbon atoms, a heteroaryl group having 2 to 14 carbon atoms, an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 6 to 10 carbon atoms, and the more preferred is hydrogen, phenyl, tolyl, xylyl, mesitylphenyl, biphenyl, pyridyl, bipyridyl, triazinyl, carbazolyl, dimethylcarbazolyl, di-tert-butylcarbazolyl, benzimidazolyl or phenylbenzimidazolyl, and the more preferred is hydrogen, phenyl or carbazolyl,

m is 1 or 2, and m is,

n is an integer of 2 to (6-m), and preferably an integer of 4 to (6-m) from the viewpoint of steric hindrance.

Further, at least one hydrogen in the compounds represented by each of the formulae may be substituted by halogen or deuterium.

Examples of the compound represented by the formula (H7) include compounds represented by the following structural formulae. In the structural formula, ". indicates a bonding position,". Me "indicates a methyl group, and" tBu "indicates a tert-butyl group.

As the compound represented by the formula (H7), PIC-TRZ, TXO-TPA, TXO-PhCz, PXZD SO2, ACRD SO2, DTC-DBT, DTAO, 4CzBN-Ph, 5CzBN, 3Cz2DPhCzBN, 4CzIPN, 2PXZ-TAZ, Cz-TRZ3, BDPCC-TPTA, MA-TA, PA-TA, FA-TA, PXZ-TRZ, DMAC-TRZ, BCzT, DCzTrz, DDCzTrz, spiro (spiroo) AC-TPZ, Ac-HPM, Ac-PPM, Ac-TRM, TCzTrz, TmCzTrz and DCzzZTrz are preferable among the specific compounds, and particularly preferable are PIC-TRZ, TXO-TPA, PXO-PhCz, ZD SO2, MPD SO 3, DTzTrz, TXCzBN-TPAD, ACRD-TPAD 9636, ACRD-TPAD-TFAD, TFAD-9636, DTZ-TPO-TPZ-TPAD, and DCzIPZ-TPAD 9636.

[ dopant Material ]

The dopant material is not particularly limited, and a known compound can be used, and can be selected from various materials according to a desired luminescent color. Specific examples thereof include: phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopyrene, dibenzopyrene, rubrene and

A condensed ring derivative, a benzoxazole derivative, a benzothiazole derivative, a benzimidazole derivative, a benzotriazole derivative, an oxazole derivative, an oxadiazole derivative, a thiazole derivative, an imidazole derivative, a thiadiazole derivative, a triazole derivative, a pyrazoline derivative, a stilbene derivative, a thiophene derivative, a tetraphenylbutadiene derivative, a cyclopentadiene derivative, a bisstyrylanthracene derivative or a distyrylbenzene derivative (Japanese patent laid-open No. 1-245087), a bisstyrylarylene derivative (Japanese patent laid-open No. 2-247278), a diazabenzodiindene derivative, a furan derivative, a benzofuran derivative, phenylisobenzofuran, ditrimethylphenylisobenzofuran, bis (2-methylphenyl) isobenzofuran, bis (2-trifluoromethylphenyl) isobenzofuran, a benzotriazole derivative, an oxadiazole derivative, a thiazole derivative, an imidazole derivative, a thiadiazole, Isobenzofuran derivatives such as phenylisobenzofuran, dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7-piperidylcoumarin derivatives, 7-hydroxycoumarin derivatives, 7-methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolyl coumarin derivatives, 3-benzimidazolylcoumarin derivatives, coumarin derivatives such as 3-benzoxazolyl coumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, polymethine derivatives, cyanine derivatives, oxobenzanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyrylium derivatives, quinolone derivatives, acridine derivatives, oxazine derivatives, phenylene ether derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, furopyridine derivatives, 1,2, 5-thiadiazolopyridine derivatives, pyrromethene derivatives, perinone derivatives, pyrrolopyrrole derivatives, squarylium salt derivatives, violanthrone derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives, benzofluorene derivatives, and the like.

In addition, polycyclic aromatic compounds described in International publication No. 2015/102118 and the like can also be used.

When each color-emitting light is exemplified, examples of the blue dopant material to the blue-green dopant material include: naphthalene, anthracene, phenanthrene, pyrene, triphenylene, perylene, fluorene, indene,

And the like, furan, pyrrole, thiophene, silole, 9-silafluorene, 9' -spirodisilylfluorene, benzothiophene, benzofuran, indole, dibenzothiophene, dibenzofuran, imidazopyridine, aromatic heterocyclic compounds such as phenanthroline, pyrazine, naphthyridine, quinoxaline, pyrrolopyridine, thioxanthene and the like or derivatives thereof, distyrylbenzene derivatives, tetraphenylbutadiene derivatives, stilbene derivatives, aldazine derivatives, coumarin derivatives, imidazole, thiazole, thiadiazole, carbazole, oxazole, oxadiazole, triazole and the like azole derivatives and metal complexes thereof, and aromatic amine derivatives represented by N, N '-diphenyl-N, N' -bis (3-methylphenyl) -4,4 '-diphenyl-1, 1' -diamine and the like.

The green to yellow dopant materials include coumarin derivatives, phthalimide derivatives, naphthalimide derivatives, perinone derivatives, pyrrolopyrrole derivatives, cyclopentadiene derivatives, acridone derivatives, quinacridone derivatives, and tetracene derivatives such as rubrene, and preferable examples thereof include: examples of the blue-green dopant material include compounds obtained by introducing a substituent capable of increasing the wavelength of light, such as an aryl group, a heteroaryl group, an arylvinyl group, an amino group, or a cyano group, into a compound exemplified as the blue-green dopant material to the blue-green dopant material.

Further, examples of the orange dopant material to the red dopant material include naphthalimide derivatives such as bis (diisopropylphenyl) perylenetetracarboxylic acid imide and the like, perinone derivatives, rare earth complexes such as Eu complexes in which acetylacetone or benzoylacetone and phenanthroline and the like are used as ligands, 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran or the like, metal phthalocyanine derivatives such as magnesium phthalocyanine and aluminum chlorophthalocyanine, rhodamine compounds, deazaflavin derivatives, coumarin derivatives, quinacridone derivatives, phenoxazine derivatives, oxazine derivatives, quinazoline derivatives, pyrrolopyridine derivatives, squarylium salt derivatives, violanthrone derivatives, phenazine derivatives, phenoxazone derivatives and thiadiazolopyridine derivatives, further, the following compounds are also included as preferable examples: examples of the blue-green-yellow dopant material and the green-yellow-green-yellow dopant material include compounds obtained by introducing a substituent capable of increasing the wavelength of light, such as an aryl group, a heteroaryl group, an arylvinyl group, an amino group, or a cyano group.

Further, the dopant can be used by appropriately selecting from compounds described in 2004, 6/13 th page and references cited therein.

Among the dopant materials, amines having a stilbene structure, perylene derivatives, borane derivatives, aromatic amine derivatives, coumarin derivatives, pyran derivatives, or pyrene derivatives are particularly preferable.

The amine having a stilbene structure is represented by, for example, the following formula.

In the formula, Ar¹Is an m-valent group derived from an aryl group having 6 to 30 carbon atoms, Ar²And Ar³Each independently an aryl group having 6 to 30 carbon atoms, Ar¹～Ar³At least one of (A) has a stilbene structure, Ar¹～Ar³May be substituted with an aryl group, a heteroaryl group, an alkyl group, a trisubstituted silyl group (a silyl group trisubstituted with an aryl group and/or an alkyl group), or a cyano group, and m is an integer of 1 to 4.

The amine having a stilbene structure is more preferably diaminostilbene represented by the following formula.

In the formula, Ar²And Ar³Each independently an aryl group having 6 to 30 carbon atoms, Ar²And Ar³May be substituted with aryl, heteroaryl, alkyl, trisubstituted silyl (silyl trisubstituted with aryl and/or alkyl) or cyano.

Specific examples of the aryl group having 6 to 30 carbon atoms include: phenyl, naphthyl, acenaphthenyl, fluorenyl, phenalkenyl, phenanthryl, anthracenyl, fluoranthenyl, triphenylenyl, pyrenyl, phenanthrenyl, triphenylenyl, phenanthrenyl,

Mesitylene, perylene, distyryl, distyrylphenyl, distyrylbiphenyl, distyrylfluorenyl, and the like.

Specific examples of the amines having a stilbene structure include: n, N, N ', N' -tetrakis (4-biphenyl) -4,4 '-diaminostilbene, N, N, N', N '-tetrakis (1-naphthyl) -4,4' -diaminostilbene, N, N ', N' -tetrakis (2-naphthyl) -4,4 '-diaminostilbene, N, N' -bis (2-naphthyl) -N, N '-diphenyl-4, 4' -diaminostilbene, N, N '-bis (9-phenanthryl) -N, N' -diphenyl-4, 4 '-diaminostilbene, 4' -bis [4 '-bis (diphenylamino) styryl ] -biphenyl, 1, 4-bis [4' -bis (diphenylamino) styryl ] -benzene, toluene, xylene, 2, 7-bis [4' -bis (diphenylamino) styryl ] -9, 9-dimethylfluorene, 4' -bis (9-ethyl-3-carbazolenyl) -biphenyl, 4' -bis (9-phenyl-3-carbazolenyl) -biphenyl, and the like.

Further, amines having a stilbene structure described in Japanese patent laid-open Nos. 2003-347056 and 2001-307884 may be used.

Examples of perylene derivatives include: 3, 10-bis (2, 6-dimethylphenyl) perylene, 3, 10-bis (2,4, 6-trimethylphenyl) perylene, 3, 10-diphenyl perylene, 3, 4-diphenyl perylene, 2,5,8, 11-tetra-tert-butylperylene, 3,4,9, 10-tetraphenylperylene, 3- (1' -pyrenyl) -8, 11-di (tert-butyl) perylene, 3- (9' -anthryl) -8, 11-di (tert-butyl) perylene, 3' -bis (8, 11-di (tert-butyl) perylenyl), and the like.

Further, perylene derivatives described in Japanese patent laid-open No. 11-97178, Japanese patent laid-open No. 2000-133457, Japanese patent laid-open No. 2000-26324, Japanese patent laid-open No. 2001-267079, Japanese patent laid-open No. 2001-267078, Japanese patent laid-open No. 2001-267076, Japanese patent laid-open No. 2000-34234, Japanese patent laid-open No. 2001-267075, and Japanese patent laid-open No. 2001-217077 may be used.

Examples of the borane derivatives include: 1, 8-diphenyl-10- (ditrimethylphenylboronyl) anthracene, 9-phenyl-10- (ditrimethylphenylboronyl) anthracene, 4- (9' -anthryl) ditrimethylphenylboronyl naphthalene, 4- (10' -phenyl-9 ' -anthryl) ditrimethylphenylboronyl naphthalene, 9- (ditrimethylphenylboronyl) anthracene, 9- (4' -biphenyl) -10- (ditrimethylphenylboronyl) anthracene, 9- (4' - (N-carbazolyl) phenyl) -10- (ditrimethylphenylboronyl) anthracene, and the like.

Further, borane derivatives described in International publication No. 2000/40586, for example, can also be used.

The aromatic amine derivative is represented by the following formula, for example.

In the formula, Ar⁴An n-valent group derived from an aryl group having 6 to 30 carbon atoms, Ar⁵And Ar⁶Each independently an aryl group having 6 to 30 carbon atoms, Ar ⁴～Ar⁶May be substituted with an aryl group, a heteroaryl group, an alkyl group, a trisubstituted silyl group (a silyl group trisubstituted with an aryl group and/or an alkyl group), or a cyano group, and n is an integer of 1 to 4.

In particular, the following aromatic amine derivatives are more preferable: ar (Ar)⁴Is derived from anthracene,

Divalent radicals of fluorene, benzofluorene or pyrene, Ar⁵And Ar⁶Each independently an aryl group having 6 to 30 carbon atoms, Ar⁴～Ar⁶Can be prepared from aryl, heteroaryl, alkyl, trisubstituted silane radicals (from aryl and/or alkyl radicals)A trisubstituted silyl group) or a cyano group, and n is 2.

Mesityl, tetracenyl, perylenyl, pentacenyl, and the like.

As aromatic amine derivatives, as

Examples of the system include: n, N, N ', N' -tetraphenyl

6, 12-diamine, N, N, N ', N' -tetrakis (p-tolyl)

6, 12-diamine, N, N, N ', N' -tetrakis (m-tolyl)

6, 12-diamine, N, N, N ', N' -tetrakis (4-isopropylphenyl)

-6, 12-diamine, N, N, N ', N' -tetrakis (naphthalen-2-yl)

6, 12-diamine, N '-diphenyl-N, N' -di (p-tolyl)

-6, 12-diamine, N '-diphenyl-N, N' -bis (4-ethylphenyl)

6, 12-diamine, N '-diphenyl-N, N' -bis (4-isopropylphenyl)

-6, 12-diamine, N '-diphenyl-N, N' -bis (4-tert-butylphenyl)

6, 12-diamine, N '-bis (4-isopropylphenyl) -N, N' -di (p-tolyl)

6, 12-diamine, and the like.

Examples of pyrene-based compounds include: n, N, N ', N ' -tetraphenylpyrene-1, 6-diamine, N, N, N ', N ' -tetra (p-tolyl) pyrene-1, 6-diamine, N, N, N ', N ' -tetra (m-tolyl) pyrene-1, 6-diamine, N, N, N ', N ' -tetra (4-isopropylphenyl) pyrene-1, 6-diamine, N, N, N ', N ' -tetra (3, 4-dimethylphenyl) pyrene-1, 6-diamine, N, N ' -diphenyl-N, N ' -di (p-tolyl) pyrene-1, 6-diamine, N, N ' -diphenyl-N, N ' -bis (4-ethylphenyl) pyrene-1, 6-diamine, N, N ' -diphenyl-N, n ' -bis (4-isopropylphenyl) pyrene-1, 6-diamine, N, N ' -diphenyl-N, N ' -bis (4-t-butylphenyl) pyrene-1, 6-diamine, N, N ' -bis (4-isopropylphenyl) -N, N ' -di (p-tolyl) pyrene-1, 6-diamine, N, N, N ', N ' -tetrakis (3, 4-dimethylphenyl) -3, 8-diphenylpyrene-1, 6-diamine, N, N-tetraphenylpyrene-1, 8-diamine, N, N ' -bis (biphenyl-4-yl) -N, N ' -diphenylpyrene-1, 8-diamine¹,N⁶-diphenyl-N¹,N⁶-bis- (4-trimethylsilyl-phenyl) -1H, 8H-pyrene-1, 6-diamine and the like.

Further, examples of anthracene series include: n, N, N, N-tetraphenylanthracene-9, 10-diamine, N, N, N ', N ' -tetra (p-tolyl) anthracene-9, 10-diamine, N, N, N ', N ' -tetra (m-tolyl) anthracene-9, 10-diamine, N, N, N ', N ' -tetra (4-isopropylphenyl) anthracene-9, 10-diamine, N, N ' -diphenyl-N, N ' -di (p-tolyl) anthracene-9, 10-diamine, N, N ' -diphenyl-N, N ' -di (m-tolyl) anthracene-9, 10-diamine, N, N ' -diphenyl-N, N ' -bis (4-ethylphenyl) anthracene-9, 10-diamine, N, N ' -diphenyl-N, n '-bis (4-isopropylphenyl) anthracene-9, 10-diamine, N, N' -diphenyl-N, N '-bis (4-tert-butylphenyl) anthracene-9, 10-diamine, N, N' -bis (4-isopropylphenyl) -N, N '-di (p-tolyl) anthracene-9, 10-diamine, 2, 6-di-tert-butyl-N, N, N', N '-tetra (p-tolyl) anthracene-9, 10-diamine, 2, 6-di-tert-butyl-N, N' -diphenyl-N, N '-bis (4-isopropylphenyl) anthracene-9, 10-diamine, 2, 6-di-tert-butyl-N, N' -bis (4-isopropylphenyl) -N, n ' -di (p-tolyl) anthracene-9, 10-diamine, 2, 6-dicyclohexyl-N, N ' -bis (4-isopropylphenyl) -N, N ' -bis (4-tert-butylphenyl) anthracene-9, 10-diamine, 9, 10-bis (4-diphenylamino-phenyl) anthracene, 9, 10-bis (4-di (1-naphthylamino) phenyl) anthracene, 9, 10-bis (4-di (2-naphthylamino) phenyl) anthracene, 10-di-p-tolylamino-9- (4-di-p-tolylamino-1-naphthyl) anthracene, 2, 6-dicyclohexyl-N, N ' -bis (4-isopropylphenyl) -N, N ' -bis (4-tert-butylphenyl) anthracene-9, 10-diamine, 9, 10-bis (4-, 10-diphenylamino-9- (4-diphenylamino-1-naphthyl) anthracene, 10-diphenylamino-9- (6-diphenylamino-2-naphthyl) anthracene, and the like.

In addition, there may be mentioned: [4- (4-diphenylamino-phenyl) naphthalen-1-yl ] -diphenylamine, [6- (4-diphenylamino-phenyl) naphthalen-2-yl ] -diphenylamine, 4 '-bis [ 4-diphenylaminonaphthalen-1-yl ] biphenyl, 4' -bis [ 6-diphenylaminonaphthalen-2-yl ] biphenyl, 4 '-bis [ 4-diphenylaminonaphthalen-1-yl ] -p-terphenyl, 4' -bis [ 6-diphenylaminonaphthalen-2-yl ] -p-terphenyl, and the like.

Further, aromatic amine derivatives described in Japanese patent laid-open publication No. 2006-156888 and the like can also be used.

Examples of the coumarin derivatives include coumarin-6 and coumarin-334.

Further, coumarin derivatives described in Japanese patent laid-open Nos. 2004-43646, 2001-76876, and 6-298758 may be used.

Examples of the pyran derivative include 4- (dicyanomethylene) -2-methyl-6- (4-dimethylaminostyryl) -4H-pyran (4- (dicyanomethylene) -2-methyl-6- (4-dimethylaminostyryl) -4H-pyran, DCM), 4- (dicyanomethylene) -2-tert-butyl-6- (1,1,7, 7-tetramethyltyrosyl-4-vinyl) -4H-pyran (4- (dicyanomethylene) -2-tert-butyl-6- (1,1,7, 7-tetramethyljunolidin-4-vinyl) -4H-pyran, DCJTB) and the like.

Further, pyran derivatives described in Japanese patent laid-open Nos. 2005-126399, 2005-097283, 2002-234892, 2001-220577, 2001-081081090, 2001-052869, and the like can also be used.

< composition for Forming light-emitting layer >

The polycyclic aromatic compound represented by the formula (1) may be used as a composition for forming a light-emitting layer together with an organic solvent. The composition contains at least one polycyclic aromatic compound as a first component, at least one host material as a second component, and at least one organic solvent as a third component. The first component functions as a dopant component of the light-emitting layer obtained from the composition, and the second component functions as a host component of the light-emitting layer. The third component functions as a solvent for dissolving the first component and the second component in the composition, and gives a smooth and uniform surface shape by utilizing a controlled evaporation rate of the third component itself at the time of application.

[ organic solvent ]

The composition for forming a light-emitting layer contains at least one organic solvent as a third component. The film forming property, the presence or absence of defects in the film, the surface roughness, and the smoothness can be controlled and improved by controlling the evaporation rate of the organic solvent during film formation. In addition, when the film is formed by the ink jet method, the stability of the meniscus (meniscus) in the pinhole of the ink jet head can be controlled, and the ejection property can be controlled and improved. In addition, by controlling the drying rate of the film and the orientation of the derivative molecules, the electrical characteristics, light-emitting characteristics, efficiency and lifetime of the organic EL element having the light-emitting layer obtained from the composition for forming a light-emitting layer can be improved.

(1) Physical Properties of organic solvent

In the third component, the boiling point of the at least one organic solvent is 130 to 300 ℃, more preferably 140 to 270 ℃, and still more preferably 150 to 250 ℃. From the viewpoint of the ejection property of the inkjet, the boiling point is preferably higher than 130 ℃. In addition, from the viewpoint of defects, surface roughness, residual solvent and smoothness of the coating film, the boiling point is preferably less than 300 ℃. The third component is more preferably a composition containing two or more organic solvents from the viewpoint of good ink-jet ejection properties, film-forming properties, smoothness, and low residual solvent. On the other hand, the composition may be made into a solid state by removing the solvent from the light-emitting layer-forming composition in consideration of the transportability and the like.

The third component further contains a Good Solvent (GS) and a Poor Solvent (PS) with respect to the host material of the second component, and particularly preferably the Boiling Point (BP) of the Good Solvent (GS)_GS) Lower than the Boiling Point (BP) of the Poor Solvent (PS)_PS) The composition of (1).

By adding poor solvent with high boiling point, the good solvent with low boiling point volatilizes first during film forming, the concentration of the content in the composition and the concentration of the poor solvent are increased, and the rapid film forming is promoted. Thus, a coating film having few defects, small surface roughness, and high smoothness can be obtained.

Difference in solubility (S)_GS-S_PS) Preferably 1% or more, more preferably 3% or more, and still more preferably 5% or more. Difference in Boiling Point (BP)_PS-BP_GS) Preferably 10 ℃ or higher, more preferably 30 ℃ or higher, and still more preferably 50 ℃ or higher.

The organic solvent is removed from the coating film by a drying step such as vacuum, reduced pressure, or heating after film formation. In the case of heating, it is preferable to perform the heating at a glass transition temperature (Tg) of the first component) +30 ℃ or lower from the viewpoint of improving the coating film formability. From the viewpoint of reducing the residual solvent, it is preferable to heat the first component at a glass transition temperature (Tg) of-30 ℃ or higher. Even if the heating temperature is lower than the boiling point of the organic solvent, the organic solvent is sufficiently removed because the film is thin. Further, the drying may be performed a plurality of times at different temperatures, or a plurality of drying methods may be used in combination.

(2) Specific examples of organic solvents

Examples of the organic solvent used in the composition for forming a light-emitting layer include alkylbenzene solvents, phenyl ether solvents, alkyl ether solvents, cyclic ketone solvents, aliphatic ketone solvents, monocyclic ketone solvents, solvents having a diester skeleton, and fluorine-containing solvents, and specific examples thereof include pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tetradecanol, hexane-2-ol, heptane-2-ol, octane-2-ol, decane-2-ol, dodecane-2-ol, cyclohexanol, α -terpineol (α -terpineol), β -terpineol, γ -terpineol, δ -terpineol, terpineol (mixture), ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, Dipropylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol isopropyl methyl ether, dipropylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol butyl methyl ether, tripropylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, ethylene glycol monophenyl ether, triethylene glycol monomethyl ether, diethylene glycol dibutyl ether, triethylene glycol butyl methyl ether, polyethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, p-xylene, m-xylene, o-xylene, 2, 6-lutidine, 2-fluoro-m-xylene, 3-fluoro-o-xylene, 2-chlorobenzotrifluoride, cumene, toluene, 2-chloro-6-fluorotoluene, 2-fluorophenylmethyl ether, anisole, 2, 3-dimethylpyrazine, bromobenzene, 4-fluorophenylmethyl ether, 3-fluorophenylmethyl ether, 3-trifluoromethylanisole, mesitylene, 1,2, 4-trimethylbenzene, tert-butylbenzene, 2-methylanisole, phenetole, benzodioxole (benzodioxole), 4-methylanisole, sec-butylbenzene, 3-methylanisole, 4-fluoro-3-methylanisole, isopropyltoluene (cymene), 1,2, 3-trimethylbenzene, 1, 2-dichlorobenzene, 2-fluorobenzonitrile, 4-fluoro-o-dimethoxybenzene (4-fluorodimethoxybenzene), 2, 6-dimethylanisole, n-butylbenzene, 3-fluorobenzonitrile, decalin (decahydronaphthalene), neopentylbenzene, 2, 5-dimethylanisole, 2, 4-dimethylanisole, benzonitrile, 3, 5-dimethylanisole, 3-dimethylanisole, 2-methylanisole, 3-methylanisole, and/5-dimethylanisole, Diphenyl ether, 1-fluoro-3, 5-dimethoxybenzene, methyl benzoate, isopentylbenzene, 3, 4-dimethylanisole, o-tolunitrile (o-tolulanie), n-pentylbenzene, o-dimethoxybenzene (veratrole), 1,2,3, 4-tetrahydronaphthalene, ethyl benzoate, n-hexylbenzene, propyl benzoate, cyclohexylbenzene, 1-methylnaphthalene, butyl benzoate, 2-methylbiphenyl, 3-phenoxytoluene, 2 '-dimethylbiphenyl (2,2' -bitolyl), dodecylbenzene, dipentylbenzene, tetramethylbenzene, trimethoxybenzene, trimethoxytoluene, 2, 3-dihydrobenzofuran, 1-methyl-4- (propoxymethyl) benzene, 1-methyl-4- (butoxymethyl) benzene, 1-methyl-4- (pentoxymethyl) benzene, 1-methyl-4- (hexyloxymethyl) benzene, 1-methyl-4- (heptyloxymethyl) benzene, benzylbutyl ether, benzylpentyl ether, benzylhexyl ether, benzylheptyl ether, benzyloctyl ether and the like, but not limited thereto. The solvents may be used alone or in combination.

[ optional Components ]

The composition for forming a light-emitting layer may contain any component within a range not impairing the properties thereof. Examples of the optional component include a binder and a surfactant.

(1) Adhesive agent

The composition for forming a light-emitting layer may contain a binder. The binder forms a film at the time of film formation, while joining the obtained film to a substrate. In addition, the composition for forming a light-emitting layer can dissolve, disperse, and bind other components.

Examples of the binder used in the composition for forming a light-emitting layer include acrylic resins, polyethylene terephthalate, Ethylene-vinyl acetate copolymers, Ethylene-vinyl alcohol copolymers, Acrylonitrile-Ethylene-Styrene copolymer (AES) resins, ionomers, chlorinated polyethers, diallyl phthalate resins, unsaturated polyester resins, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride (polyvinylidene chloride), polystyrene, polyvinyl acetate, Teflon (Teflon), Acrylonitrile-Butadiene-Styrene copolymer (Acrylonitrile-Butadiene-Styrene, ABS) resins, Acrylonitrile-Styrene copolymer (Acrylonitrile-Styrene, AS) resins, phenol resins, epoxy resins, melamine resins, urea resins, alkyd resins, Styrene resins, Polyurethane, and copolymers of the resin and the polymer, but are not limited thereto.

The binder used in the composition for forming a light-emitting layer may be one kind or a mixture of two or more kinds.

(2) Surface active agent

The composition for forming a light-emitting layer may contain a surfactant, for example, in order to control the film surface uniformity of the composition for forming a light-emitting layer, and the solvent affinity and liquid repellency of the film surface. Surfactants are classified into ionic and nonionic surfactants according to the structure of hydrophilic groups, and further classified into alkyl surfactants, silicon surfactants, and fluorine surfactants according to the structure of hydrophobic groups. Further, depending on the molecular structure, the molecular weight is classified into a simple molecular system having a relatively small molecular weight and a high molecular system having a side chain or branch having a large molecular weight. Further, the compositions are classified into a single system and a mixed system in which two or more surfactants and a base material are mixed. As the surfactant that can be used in the composition for forming a light-emitting layer, all kinds of surfactants can be used.

Examples of the surfactant include: perlipulforo (Polyflow) No.45, Perlipulforo (Polyflow) KL-245, Perlipulforo (Polyflow) No.75, Perlipulforo (Polyflow) No.90, Perlipulforo (Polyflow) No.95 (trade name, manufactured by Co., Ltd.) chemical industry, Dipper (Disperbyk)161, Dipper (Disperbyk)162, Dipper (Disperbyk)163, Dipper (Disperbyk)164, Dipper (Disperbyk)166, Dipper (Disperbyk)170, Dipper (Disperbyk)180, Dipper (Disperbyk)181, Dipper (Disperbyk)182, Byk 300, ByK 306, ByK-368, Japan, ByK-342, ByK-320, ByK 300, ByK 306, ByK-368, Japan K-330, KyK-344, KyK-320, Byk, Kogyk (Japan K)342, Byk)320, Byk, KF-96-50CS, KF-50-100CS (trade name, manufactured by shin-Etsu Chemical industries, Ltd.), Shafu Long (Surflon) SC-101, Shafu Long (Surflon) KH-40 (trade name, manufactured by Qingmei Chemical industries, Ltd.), Fujit (Ftergent)222F, Fujit (Ftergent)251, FTX-218 (trade name, manufactured by Nioes (NEOS) (stock), Aifu Tufu Long (EFTOP) EF-351, Aifu Tuo (EFTOP) EF-352, Aifu Tuo (EFTOP) EF-601, Aifu Tupo (EFTOP) EF-801, Aifu Tuo (EFTOP) 802 (trade name, manufactured by Mitsubishi materials (Mitsubishi) (stock)), Meijia Fac (Megafac) F-470, Meijiac (Megac) F-471, Meijia (Megac) EF-477, Megac) F-475, Megac (Megac) F-475, Megac-475, Meijia method (Megafac) F-479, Meijia method (Megafac) F-553, Meijia method (Megafac) F-554 (trade name, manufactured by Diesen (DIC) (Doku Co., Ltd.), fluoroalkyl benzenesulfonate, fluoroalkyl carboxylate, fluoroalkyl polyoxyethylene ether, fluoroalkyl ammonium iodide, fluoroalkyl betaine, fluoroalkyl sulfonate, diglycerin tetra (fluoroalkyl polyoxyethylene ether), fluoroalkyl trimethylammonium salt, fluoroalkyl sulfamate, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene laurate, polyoxyethylene oleate, polyoxyethylene stearate, polyoxyethylene laurylamine, sorbitan laurate, sorbitan palmitate, sorbitan stearate, sorbitan oleate, sorbitan fatty acid ester, polyoxyethylene sorbitan laurate, and the like, Polyoxyethylene sorbitan palmitate, polyoxyethylene sorbitan stearate, polyoxyethylene sorbitan oleate, polyoxyethylene naphthyl ether, alkylbenzene sulfonate and alkyldiphenyl ether disulfonate.

One kind of surfactant may be used, or two or more kinds may be used in combination.

[ composition and Properties of composition for Forming light-emitting layer ]

The content of each component in the composition for forming a light-emitting layer is preferably, from the viewpoints of good solubility, storage stability and film-forming property of each component in the composition for forming a light-emitting layer, good film quality of a coating film obtained from the composition for forming a light-emitting layer and good ejection property when an inkjet method is used, and good electrical characteristics, light-emitting characteristics, efficiency and lifetime of an organic EL element having a light-emitting layer produced using the composition: the first component is 0.0001 to 2.0% by mass based on the total mass of the composition for forming a light-emitting layer, the second component is 0.0999 to 8.0% by mass based on the total mass of the composition for forming a light-emitting layer, and the third component is 90.0 to 99.9% by mass based on the total mass of the composition for forming a light-emitting layer.

More preferably: the first component is 0.005 to 1.0 mass% based on the total mass of the composition for forming a light-emitting layer, the second component is 0.095 to 4.0 mass% based on the total mass of the composition for forming a light-emitting layer, and the third component is 95.0 to 99.9 mass% based on the total mass of the composition for forming a light-emitting layer. More preferably: the first component is 0.05 to 0.5 mass% based on the total mass of the composition for forming a light-emitting layer, the second component is 0.25 to 2.5 mass% based on the total mass of the composition for forming a light-emitting layer, and the third component is 97.0 to 99.7 mass% based on the total mass of the composition for forming a light-emitting layer.

The composition for forming a light-emitting layer can be produced by appropriately selecting the above-mentioned components by a conventional method, and stirring, mixing, heating, cooling, dissolving, dispersing, or the like. After the preparation, filtration, degassing (also referred to as degassing), ion exchange treatment, inert gas substitution, and enclosing treatment may be appropriately selected.

Regarding the viscosity of the composition for forming a light-emitting layer, a high-viscosity composition for forming a light-emitting layer can obtain good film-forming properties and good ejection properties when an ink jet method is used. On the other hand, a low-viscosity composition for forming a light-emitting layer can be easily formed into a film. Therefore, the viscosity of the composition for forming a light-emitting layer is preferably 0.3 to 3 mPas, more preferably 1 to 3 mPas, at 25 ℃. In the present invention, the viscosity is a value measured using a cone-plate type rotational viscometer (cone-plate type).

With respect to the surface tension of the composition for forming a light-emitting layer, a low surface tension can provide a coating film having good film-forming properties and no defects. On the other hand, high surface tension can achieve good ink ejection properties. Therefore, the surface tension of the composition for forming a light-emitting layer is preferably 20 to 40mN/m, more preferably 20 to 30mN/m, at 25 ℃. In the present invention, the surface tension is a value measured by the pendant drop method.

< Electron injection layer, Electron transport layer in organic electroluminescent element >

The electron injection layer 107 functions to efficiently inject electrons transferred from the cathode 108 into the light-emitting layer 105 or the electron transport layer 106. The electron transport layer 106 functions to efficiently transport electrons injected from the cathode 108 or electrons injected from the cathode 108 through the electron injection layer 107 to the light-emitting layer 105. The electron transporting layer 106 and the electron injecting layer 107 are formed by laminating and mixing one or more kinds of electron transporting and injecting materials, or are formed by mixing a mixture of an electron transporting and injecting material and a polymer binder.

The electron injection/transport layer is a layer that controls the injection of electrons from the cathode and the transport of electrons, and it is desirable that the electron injection efficiency be high and the injected electrons be transported efficiently. Therefore, a substance having a high electron affinity, a high electron mobility, and excellent stability is preferable, and impurities that become traps are less likely to be generated during production and use. However, when the balance between the transport of holes and electrons is considered, if the effect of efficiently preventing holes from the anode from flowing to the cathode side without being recombined is mainly exerted, even if the electron transport ability is not so high, the effect of improving the light emission efficiency is obtained as in the case of a material having a high electron transport ability. Therefore, the electron injection/transport layer in this embodiment may also have a function of a layer that can efficiently prevent the movement of holes.

The material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107 can be selected and used as desired from compounds conventionally used as electron transport compounds in photoconductive materials, and conventional compounds used in electron injection layers and electron transport layers of organic EL devices.

The material used for the electron transport layer or the electron injection layer preferably contains at least one selected from the following materials: a compound containing an aromatic ring or a heteroaromatic ring containing at least one atom selected from carbon, hydrogen, oxygen, sulfur, silicon, and phosphorus, a pyrrole derivative or a fused ring derivative thereof, and a metal complex having an electron-accepting nitrogen. Specifically, there may be mentioned: fused ring aromatic ring derivatives such as naphthalene and anthracene, styrene aromatic ring derivatives represented by 4,4' -bis (diphenylvinyl) biphenyl, perinone derivatives, coumarin derivatives, naphthalimide derivatives, quinone derivatives such as anthraquinone and diphenoquinone, phosphine oxide derivatives, arylnitrile derivatives, and indole derivatives. Examples of the metal complex having electron-accepting nitrogen include: and hydroxyoxazole complexes such as hydroxyphenyl oxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. These materials may be used alone or in combination with different materials.

Specific examples of the other electron transport compound include: pyridine derivatives, naphthalene derivatives, fluoranthene derivatives, BO derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives (1, 3-bis [ (4-tert-butylphenyl) 1,3, 4-oxadiazolyl ] phenylene, etc.), thiophene derivatives, triazole derivatives (N-naphthyl-2, 5-diphenyl-1, 3, 4-triazole, etc.), thiadiazole derivatives, metal complexes of 8-hydroxyquinoline derivatives, hydroxyquinoline metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzoxazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, phenanthroline derivatives, perinone or more kinds of substituted derivatives, Triazine derivatives, pyrazine derivatives, benzoquinoline derivatives (e.g., 2 '-bis (benzo [ h ] quinolin-2-yl) -9,9' -spirobifluorene), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (e.g., tris (N-phenylbenzimidazol-2-yl) benzene), benzoxazole derivatives, thiazole derivatives, benzothiazole derivatives, quinoline derivatives, terpyridine and other oligopyridine derivatives, bipyridine derivatives, terpyridine derivatives (e.g., 1, 3-bis (4'- (2, 2': 6', 2' -terpyridine)) benzene), naphthyridine derivatives (e.g., bis (1-naphthyl) -4- (1, 8-naphthyridin-2-yl) phenylphosphine oxide), aldazine derivatives, and the like, Aryl nitrile derivatives, indole derivatives, phosphine oxide derivatives, bisstyryl derivatives, silole derivatives, oxazoline derivatives, and the like.

In addition, a metal complex having electron-accepting nitrogen may also be used, and examples thereof include: hydroxyoxazole complexes such as hydroxyquinoline metal complexes and hydroxyphenyl oxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes.

The materials can be used alone or in admixture with different materials.

Among the above materials, preferred are borane derivatives, pyridine derivatives, fluoranthene derivatives, BO-based derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, arylnitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, hydroxyquinoline-based metal complexes, thiazole derivatives, benzothiazole derivatives, silole derivatives, and oxazoline derivatives.

[ borane derivatives ]

The borane derivative is, for example, a compound represented by the following formula (ETM-1), and is disclosed in detail in Japanese patent laid-open No. 2007-27587.

In the formula (ETM-1), R¹¹And R¹²Each independently is at least one of hydrogen, alkyl, aryl which may be substituted, silyl which may be substituted, nitrogen-containing heterocycle which may be substituted, or cyano, R ¹³～R¹⁶Each independently represents an alkyl group which may be substituted or an aryl group which may be substituted, X represents an arylene group which may be substituted, Y represents an aryl group having 16 or less carbon atoms which may be substituted, a substituted boron group or a substituted carbazolyl group, and n is an integer of 0 to 3.

Among the compounds represented by the above formula (ETM-1), a compound represented by the following formula (ETM-1-1) or a compound represented by the following formula (ETM-1-2) is preferable.

In the formula (ETM-1-1), R¹¹And R¹²Each independently is at least one of hydrogen, alkyl, aryl which may be substituted, silyl which may be substituted, nitrogen-containing heterocycle which may be substituted, or cyano, R¹³～R¹⁶Each independently is an alkyl group which may be substituted or an aryl group which may be substituted, R²¹And R²²Each independently is at least one of hydrogen, alkyl, aryl which may be substituted, silyl which may be substituted, nitrogen-containing heterocycle which may be substituted or cyano, X¹Is an arylene group having 20 or less carbon atoms which may be substituted, n is independently an integer of 0 to 3, and m is independently an integer of 0 to 4.

In the formula (ETM-1-2), R¹¹And R¹²Each independently is at least one of hydrogen, alkyl, aryl which may be substituted, silyl which may be substituted, nitrogen-containing heterocycle which may be substituted, or cyano, R ¹³～R¹⁶Each independently is an alkyl group which may be substituted or an aryl group which may be substituted, X¹Is an arylene group having 20 or less carbon atoms which may be substituted, and n is an integer of 0 to 3 independently.

As X¹Specific examples of (A) include divalent groups represented by the following formulae (X-1) to (X-9).

(in the formulae, R^aEach independently is an alkyl group or a substituted phenyl group, representing a bonding position)

Specific examples of the borane derivative include the following compounds.

The borane derivatives can be produced using conventional starting materials and conventional synthesis methods.

[ pyridine derivatives ]

The pyridine derivative is, for example, a compound represented by the following formula (ETM-2), and preferably a compound represented by the formula (ETM-2-1) or the formula (ETM-2-2).

Phi- (pyridine substituent)_n (ETM-2)

Phi is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), and n is an integer of 1-4.

In the formula (ETM-2-1), R¹¹～R¹⁸Each independently represents hydrogen, an alkyl group (preferably an alkyl group having 1 to 24 carbon atoms), a cycloalkyl group (preferably a cycloalkyl group having 3 to 12 carbon atoms) or an aryl group (preferably an aryl group having 6 to 30 carbon atoms).

In the formula (ETM-2-2), R¹¹And R¹²Each independently hydrogen, alkyl (preferably C1-C24 alkyl), cycloalkyl (preferably C3-C12 cycloalkyl) or aryl (preferably C6-C30 aryl), R ¹¹And R¹²May be bonded to form a ring.

In each formula, the "pyridine substituent" is any one of the following formulas (Py-1) to (Py-15) (wherein:. represents a bonding site), and each pyridine substituent is independently substituted with an alkyl group having 1 to 4 carbon atoms. In addition, the pyridine substituent may be bonded to the phi, anthracene ring or fluorene ring in each formula via phenylene or naphthylene.

The pyridine substituent is any one of the above formulae (Py-1) to (Py-15), and among these formulae, any one of the following formulae (Py-21) to (Py-44) is preferable.

At least one hydrogen of each pyridine derivative may be substituted by deuterium, and in addition, one of the two "pyridine-based substituents" in the formula (ETM-2-1) and the formula (ETM-2-2) may be substituted by an aryl group.

As R¹¹～R¹⁸The "alkyl group" in (1) may be either a straight chain or a branched chain, and examples thereof include a straight chain alkyl group having 1 to 24 carbon atoms and a branched alkyl group having 3 to 24 carbon atoms. The preferred "alkyl group" is an alkyl group having 1 to 18 carbon atoms (branched alkyl group having 3 to 18 carbon atoms). More preferably, the "alkyl group" is an alkyl group having 1 to 12 carbon atoms (branched alkyl group having 3 to 12 carbon atoms). Further preferred "alkyl group" is an alkyl group having 1 to 6 carbon atoms (branched alkyl group having 3 to 6 carbon atoms). Particularly preferred "alkyl group" is an alkyl group having 1 to 4 carbon atoms (branched alkyl group having 3 to 4 carbon atoms).

Specific examples of the "alkyl group" include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2-dimethylheptyl, 2, 6-dimethyl-4-heptyl, 3,5, 5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl and the like.

As the alkyl group having 1 to 4 carbon atoms substituted in the pyridine substituent, the description of the alkyl group can be cited.

As R¹¹～R¹⁸Examples of the "cycloalkyl group" in (1) include cycloalkyl groups having 3 to 12 carbon atoms. The preferable "cycloalkyl group" is a cycloalkyl group having 3 to 10 carbon atoms. More preferably, the "cycloalkyl group" is a cycloalkyl group having 3 to 8 carbon atoms. Further preferred "cycloalkyl group" is a cycloalkyl group having 3 to 6 carbon atoms.

Specific "cycloalkyl" groups include: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, dimethylcyclohexyl, or the like.

As R¹¹～R¹⁸The "aryl group" in (1) is preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 18 carbon atoms, still more preferably an aryl group having 6 to 14 carbon atoms, and particularly preferably an aryl group having 6 to 12 carbon atoms.

Specific examples of the "aryl group having 6 to 30 carbon atoms" include: phenyl as monocyclic aryl, (1-, 2-) naphthyl as condensed bicyclic aryl, acenaphthene- (1-, 3-, 4-, 5-) as condensed tricyclic aryl, fluorene- (1-, 2-, 3-, 4-, 9-) as non- (1-, 2-) as condensed tricyclic aryl, (1-, 2-, 3-, 4-, 9-) phenanthrene, triphenylene- (1-, 2-) as condensed tetracyclic aryl, pyrene- (1-, 2-, 4-) as condensed tetracyclic aryl, tetracene- (1-, 2-, 5-) as condensed pentacyclic aryl, perylene- (1-, 2-, 3-) as condensed tetracyclic aryl, perylene- (2-, 3-) as condensed tetracyclic aryl, perylene, and the like, Pentacene- (1-, 2-, 5-, 6-) radicals and the like.

Preferred examples of the "aryl group having 6 to 30 carbon atoms" include phenyl, naphthyl, phenanthryl,

Examples of the group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group and a phenanthryl group, and particularly preferred examples thereof include a phenyl group, a 1-naphthyl group and a 2-naphthyl group.

R in the formula (ETM-2-2)¹¹And R¹²A ring may be bonded to form a ring, and as a result, cyclobutane, cyclopentane, cyclopentene, cyclopentadiene, cyclohexane, fluorene, indene, or the like may be spiro-bonded to the 5-membered ring of the fluorene skeleton.

Specific examples of the pyridine derivative include the following compounds.

The pyridine derivative can be produced using a conventional raw material and a conventional synthesis method.

[ fluoranthene derivative ]

The fluoranthene derivative is, for example, a compound represented by the following formula (ETM-3), and is disclosed in detail in international publication No. 2010/134352.

In the formula (ETM-3), X¹²～X²¹Represents hydrogen, halogen, linear, branched or cyclic alkyl, linear, branched or cyclic alkoxy, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl.

Specific examples of the fluoranthene derivative include the following compounds.

[ BO derivative ]

The BO derivative is, for example, a polycyclic aromatic compound represented by the following formula (ETM-4) or a polymer of a polycyclic aromatic compound having a plurality of structures represented by the following formula (ETM-4).

R¹～R¹¹Each independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, alkoxy, or aryloxy, at least one of which may be substituted with aryl, heteroaryl, or alkyl.

In addition, R¹～R¹¹May be bonded to each other and together with the a-ring, the b-ring or the c-ring forms an aryl ring or a heteroaryl ring, at least one hydrogen in the formed ring may be substituted by aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, alkoxy or aryloxy, at least one of which may be substituted by aryl, heteroaryl, alkoxy or aryloxy Alkyl or aryl substituted.

In addition, at least one hydrogen in the compound or structure represented by formula (ETM-4) may be substituted with halogen or deuterium.

As to the form of the substituent or ring in the formula (ETM-4) and the polymer formed by combining the structures of the plurality of formulae (ETM-4), the polymer in International publication No. 2015/102118 will be referred to.

Specific examples of the BO-based derivative include the following compounds.

The BO-based derivative can be produced using a conventional raw material and a conventional synthesis method.

[ Anthracene derivatives ]

One of the anthracene derivatives is, for example, a compound represented by the following formula (ETM-5).

Ar¹Each independently a single bond, a divalent benzene, naphthalene, anthracene, fluorene or phenalene.

Ar²Each independently an aryl group having 6 to 20 carbon atoms, preferably an aryl group having 6 to 16 carbon atoms, more preferably an aryl group having 6 to 12 carbon atoms, and particularly preferably an aryl group having 6 to 10 carbon atoms. Specific examples of the "aryl group having 6 to 20 carbon atoms" include: phenyl group, (o, m, p) tolyl group, (2,3-, 2,4-, 2,5-, 2,6-, 3,4-, 3,5-) xylyl group, mesityl (2,4, 6-trimethylphenyl group), (o, m, p) cumenyl group as monocyclic aryl group, (2-, 3-, 4-) biphenyl group as bicyclic aryl group, (1-, 2-) naphthyl group as condensed bicyclic aryl group, (m-terphenyl-2 ' -yl group, m-terphenyl-4 ' -yl group, m-terphenyl-5 ' -yl group, o-terphenyl-3 ' -yl group, o-terphenyl-4 ' -yl group, p-terphenyl-2 ' -yl group, m-terphenyl-2-yl group, p-terphenyl-4 ' -yl group, p-terphenyl-2-yl group, p-terphenyl, M-terphenyl-3-yl, m-terphenyl-4-yl O-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, p-terphenyl-4-yl), anthracene- (1-, 2-, 9-) yl, acenaphthene- (1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalene- (1-, 2-) yl, (1-, 2-, 3-, 4-, 9-) phenanthryl as condensed tricyclic aryl, triphenylene- (1-, 2-) yl, pyrene- (1-, pyrene-3-, and perylene-4-yl as condensed tricyclic aryl, 2-, 4-) and tetracene- (1-, 2-, 5-) groups, and perylene- (1-, 2-, 3-) groups as condensed pentacyclic aryl groups. Specific examples of the "aryl group having 6 to 10 carbon atoms" include: phenyl, biphenyl, naphthyl, terphenyl, anthracenyl, acenaphthenyl, fluorenyl, phenalkenyl, phenanthrenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, and the like.

R¹～R⁴Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms or an aryl group having 6 to 20 carbon atoms.

With respect to R¹～R⁴The alkyl group having 1 to 6 carbon atoms in the group may be either a straight chain or a branched chain. Namely, a C1-6 linear alkyl group or a C3-6 branched alkyl group. More preferably an alkyl group having 1 to 4 carbon atoms (branched alkyl group having 3 to 4 carbon atoms). Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3-dimethylbutyl, and 2-ethylbutyl, and preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl, and more preferably methyl, ethyl, or tert-butyl.

As R¹～R⁴Specific examples of the cycloalkyl group having 3 to 6 carbon atoms in (b) include: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, dimethylcyclohexyl, or the like.

With respect to R¹～R⁴The aryl group having 6 to 20 carbon atoms in (A) is preferably an aryl group having 6 to 16 carbon atoms, more preferably an aryl group having 6 to 12 carbon atoms, and particularly preferably an aryl group having 6 to 10 carbon atoms. As a specific example of "aryl group having 6 to 20 carbon atoms", Ar²Specific examples of the "aryl group having 6 to 20 carbon atoms" in (1). The "aryl group having 6 to 20 carbon atoms" is preferably a phenyl group, a biphenyl group, a terphenyl group or a naphthyl group, more preferably a phenyl group, a biphenyl group, a 1-naphthyl group, a 2-naphthyl group or an m-terphenyl-5' -yl group, further preferably a phenyl group, a biphenyl group, a 1-naphthyl group or a 2-naphthyl group, and most preferably a phenyl group.

Specific examples of the anthracene derivative include the following compounds.

The anthracene derivative can be produced using an existing raw material and an existing synthesis method.

[ benzofluorene derivative ]

The benzofluorene derivative is, for example, a compound represented by the following formula (ETM-6).

Ar¹As the aryl group having 6 to 20 carbon atoms, the same description as "aryl group having 6 to 20 carbon atoms" in the formula (ETM-5-1) can be cited. Preferably an aryl group having 6 to 16 carbon atoms, more preferably an aryl group having 6 to 12 carbon atoms, and particularly preferably an aryl group having 6 to 10 carbon atoms. Specific examples thereof include: phenyl, biphenyl, naphthyl, terphenyl, anthracenyl, acenaphthenyl, fluorenyl, phenalkenyl, phenanthrenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, and the like.

Ar²Independently represents hydrogen, alkyl (preferably C1-C24 alkyl), cycloalkyl (preferably C3-C12 cycloalkyl) or aryl (preferably C6-C30 aryl), or two Ar²May be bonded to form a ring.

As Ar²The "alkyl group" in (1) may be either a straight chain or a branched chain, and examples thereof include a straight chain alkyl group having 1 to 24 carbon atoms and a branched alkyl group having 3 to 24 carbon atoms. The preferred "alkyl group" is an alkyl group having 1 to 18 carbon atoms (branched alkyl group having 3 to 18 carbon atoms). More preferablyThe "alkyl group" is an alkyl group having 1 to 12 carbon atoms (branched alkyl group having 3 to 12 carbon atoms). Further preferred "alkyl group" is an alkyl group having 1 to 6 carbon atoms (branched alkyl group having 3 to 6 carbon atoms). Particularly preferred "alkyl group" is an alkyl group having 1 to 4 carbon atoms (branched alkyl group having 3 to 4 carbon atoms). Specific examples of the "alkyl group" include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl and the like.

As Ar²Examples of the "cycloalkyl group" in (1) include cycloalkyl groups having 3 to 12 carbon atoms. The preferable "cycloalkyl group" is a cycloalkyl group having 3 to 10 carbon atoms. More preferably, the "cycloalkyl group" is a cycloalkyl group having 3 to 8 carbon atoms. Further preferred "cycloalkyl group" is a cycloalkyl group having 3 to 6 carbon atoms. Specific "cycloalkyl" groups include: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl, dimethylcyclohexyl, or the like.

As Ar²The "aryl group" in (1) is preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 18 carbon atoms, still more preferably an aryl group having 6 to 14 carbon atoms, and particularly preferably an aryl group having 6 to 12 carbon atoms.

Specific examples of the "aryl group having 6 to 30 carbon atoms" include: phenyl, naphthyl, acenaphthenyl, fluorenyl, phenalkenyl, phenanthrenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, pentacenyl, and the like.

Two Ar²A ring may be bonded to form a ring, and as a result, cyclobutane, cyclopentane, cyclopentene, cyclopentadiene, cyclohexane, fluorene, indene, or the like may be spiro-bonded to the 5-membered ring of the fluorene skeleton.

Specific examples of the benzofluorene derivative include the following compounds.

The benzofluorene derivative can be produced using conventional raw materials and conventional synthesis methods.

[ phosphine oxide derivative ]

The phosphine oxide derivative is, for example, a compound represented by the following formula (ETM-7-1). Details are also described in international publication No. 2013/079217 and international publication No. 2013/079678.

R⁵Is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 5 to 20 carbon atoms,

R⁶CN, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, heteroalkyl group having 1 to 20 carbon atoms, aryl group having 6 to 20 carbon atoms, heteroaryl group having 5 to 20 carbon atoms, alkoxy group having 1 to 20 carbon atoms or aryloxy group having 6 to 20 carbon atoms,

R⁷And R⁸Independently represents a substituted or unsubstituted aryl group having 6 to 20 carbon atoms or a heteroaryl group having 5 to 20 carbon atoms,

R⁹is oxygen or sulfur, and is selected from the group consisting of,

j is 0 or 1, k is 0 or 1, r is an integer of 0 to 4, and q is an integer of 1 to 3.

The phosphine oxide derivative may be, for example, a compound represented by the following formula (ETM-7-2).

R¹～R³Which may be the same or different, are selected from the group consisting of hydrogen, alkyl, cycloalkyl, aralkyl, alkenyl, cycloalkenyl, alkynyl, alkoxy, alkylthio, aryl ether, arylthioether, aryl, heterocyclic, halogen, cyano, formyl, carbonyl, carboxyl, amino, nitro, silyl and fused rings formed between adjacent substituents.

Ar¹May be the same or different and is an arylene or heteroarylene group, Ar²Can be the same or different and can be different,and is aryl or heteroaryl. Wherein Ar is¹And Ar²Has a substituent, or forms a condensed ring with an adjacent substituent. n is an integer of 0 to 3, and when n is 0, no unsaturated moiety is present, and when n is 3, R is not present¹。

Among these substituents, the alkyl group means, for example, a saturated aliphatic hydrocarbon group such as a methyl group, an ethyl group, a propyl group, or a butyl group, and the alkyl group may be unsubstituted or substituted. The substituent to be substituted is not particularly limited, and examples thereof include an alkyl group, an aryl group, and a heterocyclic group, and these are also common in the following description. The number of carbons of the alkyl group is not particularly limited, and is usually in the range of 1 to 20 in terms of easiness of obtaining and cost.

The cycloalkyl group means a saturated alicyclic hydrocarbon group such as a cyclopropyl group, a cyclohexyl group, a norbornyl group, an adamantyl group and the like, and the cycloalkyl group may be unsubstituted or substituted. The number of carbon atoms in the alkyl moiety is not particularly limited, and is usually within a range of 3 to 20.

The aralkyl group means an aromatic hydrocarbon group via an aliphatic hydrocarbon such as a benzyl group or a phenylethyl group, and both the aliphatic hydrocarbon and the aromatic hydrocarbon may be unsubstituted or substituted. The number of carbon atoms in the aliphatic moiety is not particularly limited, and is usually in the range of 1 to 20.

The alkenyl group means an unsaturated aliphatic hydrocarbon group containing a double bond such as a vinyl group, an allyl group, or a butadienyl group, and the alkenyl group may be unsubstituted or substituted. The number of carbon atoms of the alkenyl group is not particularly limited, and is usually in the range of 2 to 20.

The cycloalkenyl group means an unsaturated alicyclic hydrocarbon group having a double bond, such as a cyclopentenyl group, a cyclopentadienyl group, or a cyclohexenyl group, and the cycloalkenyl group may be unsubstituted or substituted.

The alkynyl group means an unsaturated aliphatic hydrocarbon group containing a triple bond such as an ethynyl group, and the alkynyl group may be unsubstituted or substituted. The carbon number of the alkynyl group is not particularly limited, and is usually in the range of 2 to 20.

The alkoxy group means, for example, an aliphatic hydrocarbon group having an ether bond such as a methoxy group, and the aliphatic hydrocarbon group may be unsubstituted or substituted. The number of carbon atoms of the alkoxy group is not particularly limited, and is usually in the range of 1 to 20.

The alkylthio group is a group in which an oxygen atom of an ether bond of an alkoxy group is substituted with a sulfur atom.

The aryl ether group means an aromatic hydrocarbon group such as a phenoxy group via an ether bond, and the aromatic hydrocarbon group may be unsubstituted or substituted. The number of carbon atoms of the aryl ether group is not particularly limited, and is usually in the range of 6 to 40.

The arylthioether group is a group in which an oxygen atom of an ether bond of an arylether group is substituted with a sulfur atom.

The aryl group represents, for example, an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, a biphenyl group, a phenanthryl group, a terphenyl group, or a pyrenyl group. The aryl group may be unsubstituted or substituted. The number of carbons of the aryl group is not particularly limited, and is usually in the range of 6 to 40.

The heterocyclic group means a cyclic structural group having an atom other than carbon, such as a furyl group, a thienyl group, an oxazolyl group, a pyridyl group, a quinolyl group, and a carbazolyl group, and the heterocyclic group may be unsubstituted or substituted. The number of carbon atoms of the heterocyclic group is not particularly limited, and is usually in the range of 2 to 30.

Halogen means fluorine, chlorine, bromine and iodine.

The formyl group, the carbonyl group, and the amino group may include a group substituted with an aliphatic hydrocarbon, an alicyclic hydrocarbon, an aromatic hydrocarbon, a heterocycle, or the like.

Further, the aliphatic hydrocarbon, alicyclic hydrocarbon, aromatic hydrocarbon, and heterocyclic ring may be unsubstituted or substituted.

The silyl group means, for example, a silicon compound group such as a trimethylsilyl group, which may be unsubstituted or substituted. The number of carbon atoms of the silyl group is not particularly limited, and is usually in the range of 3 to 20. The number of silicon is usually 1 to 6.

The condensed ring formed between the adjacent substituent(s) is, for example, Ar¹And R²、Ar¹And R³、Ar²And R²、Ar²And R³、R²And R³、Ar¹And Ar²Etc. are formed between them. Here, in the case where n is 1, two R' s¹May form conjugated or non-conjugated fused rings with each other. The condensed ring may contain a nitrogen atom, an oxygen atom, a sulfur atom in the ring inner structure, or may be further condensed with another ring.

Specific examples of the phosphine oxide derivative include the following compounds.

The phosphine oxide derivatives can be produced using existing starting materials and existing synthetic methods.

[ pyrimidine derivatives ]

The pyrimidine derivative is, for example, a compound represented by the following formula (ETM-8), and preferably a compound represented by the following formula (ETM-8-1). Details are also described in international publication No. 2011/021689.

Ar is independently aryl which may be substituted or heteroaryl which may be substituted. n is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably 2 or 3.

Examples of the "aryl group" of the "aryl group which may be substituted" include aryl groups having 6 to 30 carbon atoms, preferably aryl groups having 6 to 24 carbon atoms, more preferably aryl groups having 6 to 20 carbon atoms, and still more preferably aryl groups having 6 to 12 carbon atoms.

Specific "aryl" groups include: phenyl as a monocyclic aryl group, (2-, 3-, 4-) biphenyl as a bicyclic aryl group, (1-, 2-) naphthyl as a condensed bicyclic aryl group, (m-terphenyl-2 ' -yl, m-terphenyl-4 ' -yl, m-terphenyl-5 ' -yl, o-terphenyl-3 ' -yl, o-terphenyl-4 ' -yl, p-terphenyl-2 ' -yl, m-terphenyl-2-yl, m-terphenyl-3-yl, m-terphenyl-4-yl, o-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, p-terphenyl-1-2-naphthyl as a tricyclic aryl group, terphenyl-4 ' -yl as a tricyclic aryl group, P-terphenyl-4-yl), acenaphthylene- (1-, 3-, 4-, 5-) as condensed tricyclic aryl, fluorene- (1-, 2-, 3-, 4-, 9-) based, phenalene- (1-, 2-) based, (1-, 2-, 3-, 4-, 9-) phenanthryl, tetrabiphenyl (5' -phenyl-m-terphenyl-2-yl, 5' -phenyl-m-terphenyl-3-yl, 5' -phenyl-m-terphenyl-4-yl, m-quaterphenyl) as tetracyclic aryl, triphenylene- (1-, 2-) based as condensed tetracyclic aryl, pyrene- (1-, 2-, 4-) group, tetracene- (1-, 2-, 5-) group, perylene- (1-, 2-, 3-) group as condensed pentacyclic aryl group, pentacene- (1-, 2-, 5-, 6-) group, and the like.

Examples of the "heteroaryl group" of the "optionally substituted heteroaryl group" include a heteroaryl group having 2 to 30 carbon atoms, preferably a heteroaryl group having 2 to 25 carbon atoms, more preferably a heteroaryl group having 2 to 20 carbon atoms, still more preferably a heteroaryl group having 2 to 15 carbon atoms, and particularly preferably a heteroaryl group having 2 to 10 carbon atoms. Examples of the heteroaryl group include heterocyclic rings containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen as ring-constituting atoms in addition to carbon.

Specific examples of the heteroaryl group include: furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, oxadiazolyl, furazanyl, thiadiazolyl, triazolyl, tetrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, benzofuranyl, isobenzofuranyl, benzo [ b ] thienyl, indolyl, isoindolyl, 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxazinyl, phenothiazinyl, phenazinyl, phenoxathinyl, thianthrenyl, indolizinyl and the like.

Additionally, the aryl and heteroaryl groups may be substituted, such as by the aryl or heteroaryl groups, respectively.

Specific examples of the pyrimidine derivative include the following compounds.

The pyrimidine derivative can be produced using conventional starting materials and conventional synthetic methods.

[ aryl nitrile derivatives ]

The arylnitrile derivative is, for example, a compound represented by the following formula (ETM-9), or a multimer in which a plurality of arylnitrile derivatives are bonded by a single bond or the like. Details are described in U.S. patent application publication No. 2014/0197386.

From the viewpoint of fast electron-transporting property, Ar_niPreferably, it has a large number of carbon atoms and is higher than E_T1From the viewpoint of (1), Ar_niPreferably, the number of carbon atoms is small. Specifically, when used for a layer adjacent to the light-emitting layer, it is preferably E_T1High, thereby Ar_niThe aryl group has 6 to 20 carbon atoms, preferably 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms. In addition, the number of substitution n of nitrile groups is higher than E_T1From the viewpoint of (1), it is more preferable that E is high_S1From the viewpoint of (1), it is preferably small. Specifically, the number n of substitution of nitrile groups is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably an integer of 1 to 2, and still more preferably 1.

Ar is independently aryl which may be substituted or heteroaryl which may be substituted. Is high E_S1And high E_T1In view of the above, a donor heteroaryl group is preferable, and since it is used as an electron transporting layer, a donor heteroaryl group is preferably small. From the viewpoint of charge transport properties, aryl or heteroaryl groups having a large number of carbon atoms are preferable, and a large number of substituents are preferable. Specifically, the number m of substitution of Ar is an integer of 1 to 4, preferably an integer of 1 to 3, and more preferably 1 to 2.

The arylnitrile derivative may be a polymer in which a plurality of compounds represented by the formula (ETM-9) are bonded by a single bond or the like. In this case, the bond may be formed by an aryl ring (preferably, a polyvalent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring, or triphenylene ring) in addition to a single bond.

Specific examples of the arylnitrile derivative include the following compounds.

The aryl nitrile derivative can be produced using conventional starting materials and conventional synthesis methods.

[ triazine derivatives ]

The triazine derivative is, for example, a compound represented by the following formula (ETM-10), and preferably a compound represented by the following formula (ETM-10-1). Details are described in U.S. patent application No. 2011/0156013.

Ar is independently aryl which may be substituted or heteroaryl which may be substituted. n is an integer of 1 to 3, preferably 2 or 3.

Specific examples of the triazine derivative include the following compounds.

The triazine derivative can be produced using a conventional raw material and a conventional synthesis method.

[ benzimidazole derivatives ]

The benzimidazole derivative is, for example, a compound represented by the following formula (ETM-11).

Phi- (benzimidazole substituent) n (ETM-11)

Phi is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), n is an integer of 1 to 4, the "benzimidazole substituent" is a substituent in which the pyridyl group in the "pyridine substituent" of the formulae (ETM-2), (ETM-2-1) and (ETM-2-2) is substituted with a benzimidazole group, and at least one hydrogen in the benzimidazole derivative may be substituted with deuterium.

Denotes a bonding site.

R in said benzimidazolyl group¹¹Hydrogen, an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or an aryl group having 6 to 30 carbon atoms, and R in the above formulae (ETM-2-1) and (ETM-2-2)¹¹And (4) description.

φ is further preferably an anthracycline or fluorene ring, and the structure in this case can be referred to the description in said formula (ETM-2-1) or formula (ETM-2-2), R in each formula ¹¹～R¹⁸Reference may be made to the description in said formula (ETM-2-1) or formula (ETM-2-2). In addition, although the formula (ETM-2-1) or the formula (ETM-2-2) has been described as the form in which two pyridine substituents are bonded, when these are substituted with a benzimidazole substituent, two pyridine substituents (i.e., n ═ 2) may be substituted with the benzimidazole substituent, or one pyridine substituent may be substituted with the benzimidazole substituent and R may be substituted with the benzimidazole substituent¹¹～R¹⁸Substituted with another pyridine substituent (i.e., n ═ 1). Further, R in the formula (ETM-2-1) may be substituted with a benzimidazole-based substituent¹¹～R¹⁸And R is¹¹～R¹⁸Substituted "pyridine-based substituents".

Specific examples of the benzimidazole derivative include: 1-phenyl-2- (4- (10-phenylanthren-9-yl) phenyl) -1H-benzo [ d ] imidazole, 2- (4- (10- (naphthalen-2-yl) anthracen-9-yl) phenyl) -1-phenyl-1H-benzo [ d ] imidazole, 2- (3- (10- (naphthalen-2-yl) anthracen-9-yl) phenyl) -1-phenyl-1H-benzo [ d ] imidazole, 5- (10- (naphthalen-2-yl) anthracen-9-yl) -1, 2-diphenyl-1H-benzo [ d ] imidazole, 1- (4- (10- (naphthalen-2-yl) anthracen-9-yl) phenyl) -2-phenyl-1H-imidazole H-benzo [ d ] imidazole, 2- (4- (9, 10-di (naphthalen-2-yl) anthracen-2-yl) phenyl) -1-phenyl-1H-benzo [ d ] imidazole, 1- (4- (9, 10-di (naphthalen-2-yl) anthracen-2-yl) phenyl) -2-phenyl-1H-benzo [ d ] imidazole, 5- (9, 10-di (naphthalen-2-yl) anthracen-2-yl) -1, 2-diphenyl-1H-benzo [ d ] imidazole, and the like.

The benzimidazole derivative can be produced using conventional raw materials and conventional synthetic methods.

[ phenanthroline derivative ]

The phenanthroline derivative is, for example, a compound represented by the following formula (ETM-12) or formula (ETM-12-1). Details are described in international publication No. 2006/021982.

Of the formulae R¹¹～R¹⁸Each independently hydrogen, alkyl (preferably C1-C24 alkyl), cycloalkyl (preferably C3-C12 cycloalkyl) or aryl (preferably C6-C30 aryl). Further, in the formula (ETM-12-1), R¹¹～R¹⁸Any of these bonds to φ as an aryl ring.

At least one hydrogen in each phenanthroline derivative may be substituted by deuterium.

As R¹¹～R¹⁸Alkyl, cycloalkyl and aryl in (1), R in said formula (ETM-2) can be cited¹¹～R¹⁸And (4) description. Further, phi may be represented by the following structural formula in addition to the above examples. In the following structural formulae, R is independently hydrogen, methyl, ethyl, isopropyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenyl, or terphenyl, and represents a bonding position.

Specific examples of the phenanthroline derivative include: 4, 7-diphenyl-1, 10-phenanthroline, 2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline, 9, 10-bis (1, 10-phenanthroline-2-yl) anthracene, 2, 6-bis (1, 10-phenanthroline-5-yl) pyridine, 1,3, 5-tris (1, 10-phenanthroline-5-yl) benzene, 9' -difluoro-bis (1, 10-phenanthroline-5-yl), 2, 9-dimethyl-4, 7-biphenyl-1, 10-phenanthroline (bathocopine), 1, 3-bis (2-phenyl-1, 10-phenanthroline-9-yl) benzene, and the like.

The phenanthroline derivative can be produced using a conventional raw material and a conventional synthesis method.

[ hydroxyquinoline-based metal complex ]

The hydroxyquinoline metal complex is, for example, a compound represented by the following formula (ETM-13).

In the formula, R¹～R⁶Is hydrogen or a substituent, M is Li, Al, Ga, Be or Zn, and n is an integer of 1-3.

Specific examples of the hydroxyquinoline metal complex include: lithium 8-quinolinolate, aluminum tris (8-quinolinolate), aluminum tris (4-methyl-8-quinolinolate), aluminum tris (5-methyl-8-quinolinolate), aluminum tris (3, 4-dimethyl-8-quinolinolate), aluminum tris (4, 5-dimethyl-8-quinolinolate), aluminum tris (4, 6-dimethyl-8-quinolinolate), aluminum bis (2-methyl-8-quinolinolate) (phenoxide), aluminum bis (2-methyl-8-quinolinolate) (2-methylphenol), aluminum bis (2-methyl-8-quinolinolate) (3-methylphenol), aluminum bis (2-methyl-8-quinolinolate) (4-methylphenol), aluminum tris (4-methyl-8-quinolinolate), Bis (2-methyl-8-quinolinolato) (2-phenylphenol) aluminum, bis (2-methyl-8-quinolinolato) (3-phenylphenol) aluminum, bis (2-methyl-8-quinolinolato) (4-phenylphenol) aluminum, bis (2-methyl-8-quinolinolato) (2, 3-dimethylphenol) aluminum, bis (2-methyl-8-quinolinolato) (2, 6-dimethylphenol) aluminum, bis (2-methyl-8-quinolinolato) (3, 4-dimethylphenol) aluminum, bis (2-methyl-8-quinolinolato) (3, 5-dimethylphenol) aluminum, bis (2-methyl-8-quinolinolato) (3, 5-di-tert-butylphenol) aluminum, bis (2-methyl-8-quinolinolato) (2, 6-diphenylphenol) aluminum, bis (2-methyl-8-quinolinolato) (2, 4, 6-triphenylpheno) aluminum, bis (2-methyl-8-quinolinolato) (2, 4, 6-trimethylphenol) aluminum, bis (2-methyl-8-quinolinolato) (2, 4, 5, 6-tetramethylphenol) aluminum, bis (2-methyl-8-quinolinolato) (1-naphthol) aluminum, bis (2-methyl-8-quinolinolato) (2-naphthol) aluminum, bis (2, 4-dimethyl-8-quinolinolato) (2-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2-naphthol) aluminum, bis (2, 4-dimethyl-8-quinolinolato) (3-phenylphenol) aluminum, bis (2, 4-dimethyl-8-quinolinolato) (4-phenylphenol) aluminum, bis (2, 4-dimethyl-8-quinolinolato) (3, 5-dimethylphenol) aluminum, bis (2, 4-dimethyl-8-quinolinolato) (3, 5-di-tert-butylphenol) aluminum, bis (2-methyl-8-quinolinolato) aluminum- μ -oxo-bis (2-methyl-8-quinolinolato) aluminum, bis (2, 4-dimethyl-8-quinolinolato) aluminum- μ -oxo-bis (2, 4-dimethyl-8-quinolinolato) aluminum, aluminum, Bis (2-methyl-4-ethyl-8-quinolinolato) aluminum- μ -oxo-bis (2-methyl-4-ethyl-8-quinolinolato) aluminum, bis (2-methyl-4-methoxy-8-quinolinolato) aluminum- μ -oxo-bis (2-methyl-4-methoxy-8-quinolinolato) aluminum, bis (2-methyl-5-cyano-8-quinolinolato) aluminum- μ -oxo-bis (2-methyl-5-cyano-8-quinolinolato) aluminum, bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum- μ -oxo-bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum -hydroxyquinoline) aluminum, bis (10-hydroxybenzo [ h ] quinoline) beryllium, and the like.

The hydroxyquinoline metal complex can be produced using a conventional raw material and a conventional synthesis method.

[ thiazole derivatives and benzothiazole derivatives ]

Examples of the thiazole derivative include compounds represented by the following formula (ETM-14-1).

Phi- (azole group substituent) n (ETM-14-1)

The benzothiazole derivative is, for example, a compound represented by the following formula (ETM-14-2).

Phi- (benzothiazole substituent) n (ETM-14-2)

Phi is an n-valent aryl ring (preferably an n-valent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring or triphenylene ring), n is an integer of 1 to 4, and the "thiazole substituent" or "benzothiazole substituent" is a substituent in which a pyridyl group in the "pyridine substituent" of the formulae (ETM-2), (ETM-2-1) and (ETM-2-2) is substituted with a thiazolyl group or a benzothiazolyl group, and at least one of the thiazole derivative and the benzothiazole derivative may be substituted with deuterium.

Denotes a bonding site.

φ is further preferably an anthracycline or fluorene ring, and the structure in this case can be referred to the description in said formula (ETM-2-1) or formula (ETM-2-2), R in each formula¹¹～R¹⁸Reference may be made to the description in said formula (ETM-2-1) or formula (ETM-2-2). In addition, although the formula (ETM-2-1) or the formula (ETM-2-2) has been described as a form in which two pyridine substituents are bonded, when these are substituted with a thiazole substituent (or a benzothiazole substituent), two pyridine substituents (that is, n ═ 2) may be substituted with a thiazole substituent (or a benzothiazole substituent), and one of the pyridine substituents may be substituted with a thiazole substituent (or a benzothiazole substituent) and R may be substituted with an R ¹¹～R¹⁸Substituted with another pyridine substituent (i.e., n ═ 1). Further, R in the formula (ETM-2-1) may be substituted with a thiazole-based substituent (or a benzothiazole-based substituent), for example¹¹～R¹⁸And R is¹¹～R¹⁸Substituted "pyridine-based substituents".

The thiazole derivative or the benzothiazole derivative can be produced using a conventional raw material and a conventional synthesis method.

[ Silole derivatives ]

Examples of the silole derivative include compounds represented by the following formula (ETM-15). The details are described in Japanese patent laid-open No. 9-194487.

X and Y are each independently alkyl, cycloalkyl, alkenyl, alkynyl, alkoxy, alkenyloxy, alkynyloxy, aryl, heteroaryl, which may be substituted. As for the details of these groups, the descriptions in the formulae (1) and (2) and the description in the formula (ETM-7-2) can be cited. In addition, alkenyloxy and alkynyloxy are each a group in which an alkyl moiety in an alkoxy group is substituted with an alkenyl group or an alkynyl group, and the details of the alkenyl group and the alkynyl group can be referred to the description in the formula (ETM-7-2).

In addition, X and Y, both of which are alkyl groups, may be bonded to form a ring.

R¹～R⁴Each independently is hydrogen, halogen, alkyl, cycloalkyl, alkoxy, aryloxy, amino, alkylcarbonyl, arylcarbonyl, Alkoxycarbonyl, aryloxycarbonyl, azo, alkylcarbonyloxy, arylcarbonyloxy, alkoxycarbonyloxy, aryloxycarbonyloxy, sulfinyl, sulfonyl, mercapto, silyl, carbamoyl, aryl, heteroaryl, alkenyl, alkynyl, nitro, formyl, nitroso, formyloxy, isocyano, cyanate, isocyanate, thiocyanate, isothiocyanate or cyano, which may be substituted with alkyl, cycloalkyl, aryl or halogen, or may form a fused ring with an adjacent substituent.

With respect to R¹～R⁴The halogen, alkyl, cycloalkyl, alkoxy, aryloxy, amino, aryl, heteroaryl, alkenyl and alkynyl in (1) and (2) can be cited as detailed in the description.

With respect to R¹～R⁴In the above (1), the alkyl, aryl and alkoxy groups in the alkylcarbonyl, arylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, alkylcarbonyloxy, arylcarbonyloxy, alkoxycarbonyloxy and aryloxycarbonyloxy groups can be mentioned in detail as well as the descriptions in the formulae (1) and (2).

Examples of the silyl group include a silyl group and a group in which at least one of the three hydrogens of the silyl group is independently substituted with an aryl group, an alkyl group or a cycloalkyl group, preferably a trisubstituted silyl group, and examples thereof include: triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkylbicycloalkylsilyl, and the like. As for details of the aryl group, the alkyl group and the cycloalkyl group, the descriptions in the formula (1) and the formula (2) can be cited.

The condensed ring formed between the adjacent substituent is, for example, R¹And R²、R²And R³、R³And R⁴Etc. are formed between them. These condensed rings may contain a nitrogen atom, an oxygen atom, a sulfur atom in the ring inner structure, and may be condensed with other rings.

Among them, the compound is preferably represented by the formula R¹And R⁴In the case of phenyl, X and Y are not alkyl or phenyl. In addition, it is preferable that R is¹And R⁴In the case of thienyl, X and Y do not simultaneously satisfy alkyl and R²And R³Do not simultaneously satisfy alkyl, aryl, alkenyl or R²And R³A cycloalkyl group bonded to form a ring. In addition, it is preferable that R is¹And R⁴In the case of a silane group, R²、R³X and Y are each independently not hydrogen or alkyl of 1 to 6 carbon atoms. In addition, it is preferable that when R is in¹And R²When a benzene ring is condensed on the above-mentioned group, X and Y are not an alkyl group or a phenyl group.

The silole derivative can be produced using conventional starting materials and conventional synthetic methods.

[ oxazoline derivatives ]

The oxazoline derivative is, for example, a compound represented by the following formula (ETM-16). Details are described in international publication No. 2017/014226.

In the formula (ETM-16),

phi is an m-valent group derived from an aromatic hydrocarbon having 6 to 40 carbon atoms or an m-valent group derived from an aromatic heterocycle having 2 to 40 carbon atoms, at least one hydrogen of phi is substituted by an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aryl group having 6 to 18 carbon atoms or a heteroaryl group having 2 to 18 carbon atoms,

Y is-O-, -S-or > N-Ar, Ar is aryl with 6-12 carbon atoms or heteroaryl with 2-12 carbon atoms, at least one hydrogen of Ar is substituted by alkyl with 1-4 carbon atoms, cycloalkyl with 5-10 carbon atoms, aryl with 6-12 carbon atoms or heteroaryl with 2-12 carbon atoms, R is¹～R⁵Each independently represents hydrogen, an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 5 to 10 carbon atoms, wherein Ar in the above-mentioned formula > N-Ar and R are¹～R⁵Any one of which is a site bonded to L,

l is independently selected from the group consisting of a divalent group represented by the following formula (L-1) and a divalent group represented by the following formula (L-2),

in the formula (L-1), X¹～X⁶Each independently is ═ CR⁶-or ═ N-, X¹～X⁶At least two of which are ═ CR⁶-，X¹～X⁶Two of (CR)⁶R in (A-C)⁶Is a site bonded to the phi or oxazoline ring, other than CR⁶R in (A-C)⁶Is a hydrogen atom, and is,

in the formula (L-2), X⁷～X¹⁴Each independently is ═ CR⁶-or ═ N-, X⁷～X¹⁴At least two of which are ═ CR⁶-，X⁷～X¹⁴Two of (CR)⁶R in (A-C)⁶Is a site bonded to the phi or oxazoline ring, other than CR⁶R in (A-C)⁶Is a hydrogen atom, and is,

at least one hydrogen of L is substituted by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms or a heteroaryl group having 2 to 10 carbon atoms,

m is an integer of 1 to 4, and when m is 2 to 4, the groups formed by the oxazoline ring and L may be the same or different, and,

At least one hydrogen in the compound represented by formula (ETM-16) may be substituted with deuterium.

The specific oxazoline derivative is a compound represented by the following formula (ETM-16-1) or formula (ETM-16-2).

In the formulae (ETM-16-1) and (ETM-16-2),

in the formula (ETM-16-1), Y is-O-, -S-or > N-Ar, Ar is aryl with 6-12 carbon atoms or heteroaryl with 2-12 carbon atoms, at least one hydrogen of Ar is substituted by alkyl with 1-4 carbon atoms, cycloalkyl with 5-10 carbon atoms, aryl with 6-12 carbon atoms or heteroaryl with 2-12 carbon atoms,

in the formula (ETM-16-1), R¹～R⁴Each independently hydrogen, C1-C4 alkyl or C5-C10 cycloalkyl, wherein R is¹And R²Are the same, and R³And R⁴In the same way, the first and second,

in the formula (ETM-16-2), R¹～R⁵Each independently hydrogen, C1-C4 alkyl or C5-C10 cycloalkyl, wherein R is¹And R²Are the same, and R³And R⁴In the same way, the first and second,

in the formulae (ETM-16-1) and (ETM-16-2),

at least one hydrogen in the compound represented by formula (ETM-16-1) or formula (ETM-16-2) may be substituted with deuterium.

Preferably: and phi is selected from the group consisting of a monovalent group represented by the following formulas (phi 1-1) to (phi 1-18), a divalent group represented by the following formulas (phi 2-1) to (phi 2-34), a trivalent group represented by the following formulas (phi 3-1) to (phi 3-3), and a tetravalent group represented by the following formulas (phi 4-1) to (phi 4-2), wherein at least one hydrogen of phi is substituted by an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aryl group having 6 to 18 carbon atoms, or a heteroaryl group having 2 to 18 carbon atoms.

Wherein Z is > CR₂N-Ar, > N-L, -O-or-S-, > CR₂Wherein R is independently an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms or a heteroaryl group having 2 to 12 carbon atoms, R may be bonded to each other to form a ring, > Ar in N-Ar is an aryl group having 6 to 12 carbon atoms or a heteroaryl group having 2 to 12 carbon atoms, > L in N-L is L in the formula (ETM-16), the formula (ETM-16-1) or the formula (ETM-16-2). Wherein denotes a bonding site.

Preferably: l is a divalent group of a ring selected from the group consisting of benzene, naphthalene, pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, isoquinoline, naphthyridine, phthalazine, quinoxaline, quinazoline, cinnoline and pteridine, and at least one hydrogen of L is substituted by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms or a heteroaryl group having 2 to 10 carbon atoms.

Preferably: ar in > N-Ar as Y or Z is selected from the group consisting of phenyl, naphthyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, quinolyl, isoquinolyl, naphthyridinyl, phthalazinyl, quinoxalinyl, quinazolinyl, cinnolinyl and pteridinyl, and at least one hydrogen of Ar in > N-Ar as Y is substituted by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms.

Preferably: r¹～R⁴Each independently hydrogen, C1-C4 alkyl or C5-C10 cycloalkyl, wherein R is¹And R²Same as R³And R⁴Are the same, and R¹～R⁴All of which are not simultaneously hydrogen, and m is 1 or 2, and when m is 2, the same group is formed by the oxazoline ring and L.

Specific examples of the oxazoline derivative include the following compounds. Further, "Me" in the structural formula represents a methyl group.

More preferably: φ is selected from the group consisting of divalent radicals represented by the following formulae (φ 2-1), (φ 2-31), formulae (φ 2-32), formulae (φ 2-33), and formulae (φ 2-34), wherein at least one hydrogen of φ is substituted by an aryl group having 6 to 18 carbon atoms,

(indicates bonding position)

L is a divalent group of a ring selected from the group consisting of benzene, pyridine, pyrazine, pyrimidine, pyridazine and triazine, at least one hydrogen of L is substituted by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms or a heteroaryl group having 2 to 14 carbon atoms,

ar in > N-Ar as Y is selected from the group consisting of phenyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl and triazinyl, wherein at least one hydrogen of Ar is substituted by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms,

R¹～R⁴Independently represents hydrogen, alkyl group having 1 to 4 carbon atoms or 5 to c10 cycloalkyl, wherein R¹And R²Same as R³And R⁴Are the same, and R¹～R⁴All of which do not simultaneously become hydrogen, and,

m is 2 and the group formed by the oxazoline ring and L is the same.

Other specific examples of the oxazoline derivative include the following compounds. Further, "Me" in the structural formula represents a methyl group.

With respect to details of the alkyl group, cycloalkyl group, aryl group or heteroaryl group in the formulae for specifying the oxazoline derivative, the descriptions in the formulae (1) and (2) may be cited.

The oxazoline derivative can be produced using an existing raw material and an existing synthesis method.

[ reducing substances, others ]

The electron transport layer or the electron injection layer may further contain a substance capable of reducing a material forming the electron transport layer or the electron injection layer. As the reducing substance, various substances can be used as long as they have a certain reducing property, and for example, at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, oxides of alkali metals, halides of alkali metals, oxides of alkaline earth metals, halides of alkaline earth metals, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals, and organic complexes of rare earth metals can be preferably used.

Preferable reducing substances include alkali metals such as Na (work function 2.36eV), K (work function 2.28eV), Rb (work function 2.16eV), and Cs (work function 1.95eV), and alkaline earth metals such as Ca (work function 2.9eV), Sr (work function 2.0 to 2.5eV), and Ba (work function 2.52eV), and particularly preferable substances have a work function of 2.9eV or less. Among these, K, Rb or Cs is more preferable as the reducing substance, Rb or Cs is more preferable, and Cs is most preferable. The alkali metal has particularly high reducing power, and by adding a relatively small amount of the alkali metal to a material forming the electron transporting layer or the electron injecting layer, improvement in light emission luminance or prolongation in the organic EL element can be achieved. In addition, as the reducing substance having a work function of 2.9eV or less, a combination of two or more kinds of the alkali metals is also preferable, and a combination including Cs, for example, a combination of Cs and Na, a combination of Cs and K, Cs and Rb, or a combination of Cs and Na and K is particularly preferable. By including Cs, the reducing ability can be efficiently exerted, and by adding Cs to a material for forming an electron transporting layer or an electron injecting layer, improvement in light emission luminance or prolongation in life of the organic EL element can be achieved.

< cathode in organic electroluminescent element >

The cathode 108 functions to inject electrons into the light-emitting layer 105 through the electron injection layer 107 and the electron transport layer 106.

The material forming the cathode 108 is not particularly limited as long as it can efficiently inject electrons into the organic layer, and the same material as the material forming the anode 102 can be used. Among them, metals such as tin, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium, and magnesium, and alloys thereof (e.g., magnesium-silver alloys, magnesium-indium alloys, and aluminum-lithium alloys such as lithium fluoride and aluminum) are preferable. In order to improve the electron injection efficiency to improve the element characteristics, it is effective to use lithium, sodium, potassium, cesium, calcium, magnesium, or an alloy containing the low work function metal. However, the low work function metal is generally unstable in the atmosphere in many cases. In order to improve the above-mentioned aspect, for example, a method of doping a minute amount of lithium, cesium, or magnesium in an organic layer and using an electrode having high stability is known. As other dopants, inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide, and cesium oxide can also be used. However, the present invention is not limited to these examples.

Further, the following preferable examples are listed: metals such as platinum, gold, silver, copper, iron, tin, aluminum, and indium or alloys using the metals for protecting the electrodes; and inorganic substances such as silicon dioxide, titanium dioxide, and silicon nitride; polyvinyl alcohol, vinyl chloride, hydrocarbon-based polymer compounds, and the like. The method of manufacturing the electrode is not particularly limited as long as conduction can be achieved by resistance heating, electron beam evaporation, sputtering, ion plating, coating, or the like.

< Binders usable in the layers >

The materials used for the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer may be used individually for each layer, or may be dispersed in a solvent-soluble resin such as polyvinyl chloride, polycarbonate, polystyrene, poly (N-vinylcarbazole), polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene ether, polybutadiene, a hydrocarbon resin, a ketone resin, a phenoxy resin, polyamide, ethyl cellulose, a vinyl acetate resin, an acrylonitrile-butadiene-styrene (ABS) resin, or a polyurethane resin as a polymer binder, or a curable resin such as a phenol resin, a xylene resin, a petroleum resin, a urea resin, a melamine resin, an unsaturated polyester resin, an alkyd resin, an epoxy resin, or a silicone resin.

< method for manufacturing organic electroluminescent element >

Each layer constituting the organic electroluminescent element can be formed by forming a material constituting each layer into a thin film by a method such as vapor deposition, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination, printing, spin coating, casting, or coating. The film thickness of each layer formed in the above-described manner is not particularly limited, and may be appropriately set according to the properties of the material, but is usually in the range of 2nm to 5000 nm. The film thickness can be measured by a quartz oscillation type film thickness measuring apparatus or the like.

When a dc voltage is applied to the organic electroluminescent element obtained as described above, the anode may be applied with a + polarity and the cathode may be applied with a-polarity, and when a voltage of about 2V to 40V is applied, light emission can be observed from the transparent or translucent electrode side (anode or cathode or both). In addition, the organic electroluminescent element emits light even when a pulse current or an alternating current is applied thereto. Further, the waveform of the applied alternating current may be arbitrary.

Next, as an example of a method for manufacturing an organic electroluminescent element, a method for manufacturing an organic electroluminescent element including an anode, a hole injection layer, a hole transport layer, a light-emitting layer including a host material and a dopant material, an electron transport layer, an electron injection layer, and a cathode will be described.

[ vapor deposition method ]

An anode is formed by forming a thin film of an anode material on an appropriate substrate by vapor deposition or the like, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. The target organic electroluminescent element can be obtained by forming a thin film as a light-emitting layer by co-evaporating a host material and a dopant material on the thin film, forming an electron transport layer and an electron injection layer on the light-emitting layer, and further forming a thin film containing a substance for a cathode as a cathode by an evaporation method or the like. In the production of the organic electroluminescent element, the cathode, the electron injection layer, the electron transport layer, the light-emitting layer, the hole transport layer, the hole injection layer, and the anode may be produced in the order of reverse production.

When a thin film is formed by a vapor deposition method, the vapor deposition conditions vary depending on the type of material, the target crystal structure and the association structure of the film, and the like. The deposition conditions are preferably, in general, a heating temperature of +50 ℃ to +400 ℃ and a degree of vacuum of 10 ℃ in a crucible for deposition^-6Pa～10^-3Pa, a deposition rate of 0.01nm/sec to 50nm/sec, a substrate temperature of-150 ℃ to +300 ℃, and a film thickness of 2nm to 5 μm.

[ Wet film formation method ]

A low-molecular compound capable of forming each organic layer of an organic EL element is prepared as a liquid composition for forming an organic layer, and a wet film formation method is performed using the low-molecular compound. In the case where an appropriate organic solvent for dissolving the low-molecular compound is not present, the composition for forming an organic layer may be prepared from a high-molecular compound obtained by polymerizing the low-molecular compound as a reactive compound in which a reactive substituent is substituted in the low-molecular compound together with another monomer having a solubility function or a main chain polymer, or the like.

The composition for forming a light-emitting layer is an example of a composition for forming an organic layer, and the light-emitting layer formed using the composition for forming an organic layer can be formed by a wet film-forming method. As for the organic solvent or optional components to be used for the preparation of the composition for forming an organic layer, and the physical properties of the composition, reference is made to the description of the composition for forming a light-emitting layer.

In general, a wet film-forming method forms a coating film by passing through a coating step of coating a substrate with an organic layer-forming composition and a drying step of removing a solvent from the coated organic layer-forming composition. Depending on the coating process, a method using a spin coater is called a spin coating method, a method using a slit coater is called a slit coating method, a method using a plate is called a gravure, offset, reverse offset, or flexo printing method, a method using an ink jet printer is called an ink jet method, and a method of spraying in a mist form is called a spray method. The drying step may be carried out by air drying, heating, drying under reduced pressure, or the like. The drying step may be performed only once, or may be performed a plurality of times by using different methods or conditions. Alternatively, for example, a different method may be used in combination as calcination under reduced pressure.

The wet film formation method is a film formation method using a solution, and examples thereof include a partial printing method (ink jet method), a spin coating method, a casting method, and a coating method. Unlike the vacuum deposition method, the wet film formation method can form a film under atmospheric pressure without using an expensive vacuum deposition apparatus. In addition, the wet film forming method can be used for large-area production or continuous production, which leads to reduction in production cost.

On the other hand, the wet film formation method is less likely to form a multilayer structure than the vacuum deposition method. In the case of producing a laminated film by a wet film formation method, it is necessary to prevent dissolution of a lower layer by a composition of an upper layer, and to use a composition having controlled solubility, crosslinking of a lower layer, and an Orthogonal solvent (mutually insoluble solvent). However, even when such a technique is used, it is sometimes difficult to apply a wet film formation method to all the films.

Therefore, the following method is generally employed: only a plurality of layers were formed by a wet film formation method, and the remaining layers were formed by a vacuum deposition method, thereby producing an organic EL element.

For example, a part of the process for producing an organic EL element by a wet film formation method is shown below.

(step 1) formation of film on anode by vacuum deposition

(step 2) film formation of hole injection layer by Wet film formation method

(step 3) film formation of hole transport layer by Wet film formation method

(step 4) film formation by a Wet film formation method of a composition for light-emitting layer formation comprising a host material and a dopant material

(step 5) deposition of the Electron transport layer by vacuum deposition

(step 6) deposition of the Electron injection layer by vacuum deposition

(step 7) film formation of cathode by vacuum vapor deposition

By passing through the above-described procedure, an organic EL element including an anode/a hole injection layer/a hole transport layer/a light emitting layer including a host material and a dopant material/an electron transport layer/an electron injection layer/a cathode can be obtained.

Of course, the electron transport layer and the electron injection layer may be formed by a wet film formation method using a composition for layer formation containing a material for the electron transport layer and a material for the electron injection layer, respectively. In this case, it is preferable to use a means for preventing the light-emitting layer of the underlayer from dissolving or a means for forming a film from the cathode side in the reverse of the above-mentioned step.

[ other film formation method ]

For forming a film of the composition for forming a light-emitting layer, a Laser Induced Thermal Imaging (LITI) method may be used. LITI is a method of heating and depositing a compound attached to a substrate by a laser beam, and a composition for forming a light-emitting layer can be used for a material to be coated on a substrate.

< optional Process >

Before and after each step of film formation, an appropriate treatment step, cleaning step and drying step may be added as appropriate. Examples of the treatment step include: exposure treatment, plasma surface treatment, ultrasonic treatment, ozone treatment, cleaning treatment with an appropriate solvent, heat treatment, and the like. Further, a series of steps for producing the bank may be mentioned.

Photolithography techniques may be used in the fabrication of the banks. As the bank material which can be used for photolithography, a positive resist material and a negative resist material can be used. Further, a printing method capable of forming a pattern, such as an ink jet method, gravure offset printing, reverse offset printing, or screen printing, may be used. At this time, a permanent resist material may also be used.

Examples of the material used for the bank include polysaccharides and derivatives thereof, homopolymers and copolymers of vinyl monomers having a hydroxyl group, biopolymer compounds, polyacryl compounds, polyesters, polystyrene, polyimide, polyamideimide, polyetherimide, polythioether, polysulfone, polyphenylene (phenylene), polyphenylene ether (polyphenylether), polyurethane, epoxy (meth) acrylate, melamine (meth) acrylate, polyolefin, cyclic polyolefin, acrylonitrile-butadiene-styrene copolymer (ABS), silicone resins, polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, polyacetate, polynorbornene, synthetic rubbers, fluorinated polymers such as polyvinylidene fluoride, polytetrafluoroethylene, and polyhexafluoropropylene, copolymerized polymers of fluoroolefin-hydrocarbon olefin, and fluorocarbon polymers, but is not limited thereto.

A method for manufacturing an organic EL element on a substrate having a bank by an ink-jet method will be described with reference to fig. 2. First, the bank 200 is disposed on the electrode 120 on the substrate 110. In this case, droplets 310 of the ink may be dropped from the ink jet head 300 to between the banks 200 and dried to produce the coating film 130. By repeating the above steps to form the next coating film 140 and further to the light-emitting layer 150, and by forming the electron transport layer, the electron injection layer, and the electrode by vacuum deposition, an organic EL element having light-emitting portions divided by the bank material can be produced.

< example of application of organic electroluminescent element >

In addition, the present invention is also applicable to a display device including an organic electroluminescence element, an illumination device including an organic electroluminescence element, or the like.

The display device or the lighting device including the organic electroluminescent element can be manufactured by a conventional method such as connecting the organic electroluminescent element of this embodiment mode to a conventional driving device, and can be suitably driven by a conventional driving method such as dc driving, pulse driving, or ac driving.

Examples of the display device include: a panel display such as a color flat panel display, a flexible display such as a flexible color organic Electroluminescence (EL) display, and the like (for example, refer to japanese patent laid-open No. 10-335066, japanese patent laid-open No. 2003-321546, and japanese patent laid-open No. 2004-281086). Examples of the display mode of the display include a matrix mode and a segment mode. Further, the matrix display and the segment display may coexist in the same screen (panel).

In the matrix, pixels for display are two-dimensionally arranged in a lattice shape, a mosaic shape, or the like, and characters or images are displayed by a set of pixels. The shape or size of the pixel is determined according to the application. For example, in image and character display of a personal computer, a monitor, and a television, a rectangular pixel having a side of 300 μm or less is generally used, and in the case of a large-sized display such as a display screen, a pixel having a side of mm level is used. In the case of monochrome display, pixels of the same color may be arranged, and in the case of color display, pixels of red, green, and blue are arranged in parallel to perform display. In this case, a triangular shape and a striped shape are typical. Also, as a driving method of the matrix, any one of a line-sequential (line-sequential) driving method or an active matrix may be used. The line sequential driving has an advantage of a simple structure, but when the operation characteristics are taken into consideration, the active matrix is sometimes more excellent, and therefore the driving method must be used separately depending on the application.

In the segment method (type), a pattern is formed so as to display information determined in advance, and the determined region is caused to emit light. Examples thereof include: time and temperature display in a digital clock or a thermometer, operation state display of an audio device or an induction cooker, panel display of an automobile, and the like.

Examples of the lighting device include: a lighting device such as an indoor lighting, a backlight of a liquid crystal display device, and the like (for example, refer to japanese patent laid-open nos. 2003-257621, 2003-277741, 2004-119211, and the like). Backlights are used mainly for improving visibility of display devices that do not emit light, and are used for liquid crystal display devices, clocks, audio devices, automobile panels, display panels, signs, and the like. In particular, as a backlight for personal computer applications in which thinning of a liquid crystal display device is an issue, considering that thinning is difficult in the conventional system including a fluorescent lamp or a light guide plate, the backlight using the light emitting element of the present embodiment has features of thinness and lightweight.

3-2. other organic devices

The polycyclic aromatic compound of the present invention can be used not only for the production of the organic electroluminescent element but also for the production of an organic field effect transistor, an organic thin film solar cell, or the like.

The organic field effect transistor is a transistor for controlling current by an electric field generated by voltage input, and includes not only a source electrode and a drain electrode but also a gate electrode. And is a transistor as follows: when a voltage is applied to the gate electrode, an electric field is generated, and the flow of electrons (or holes) flowing between the source electrode and the drain electrode is arbitrarily blocked to control the current. A field effect transistor is easy to be miniaturized compared with a single transistor (bipolar transistor), and is often used as an element constituting an integrated circuit or the like.

In general, the organic field effect transistor may be configured such that an active electrode and a drain electrode are provided in contact with an organic semiconductor active layer formed using the polycyclic aromatic compound of the present invention, and a gate electrode is provided through an insulating layer (dielectric layer) in contact with the organic semiconductor active layer. Examples of the element structure include the following structures.

(1) Substrate/gate electrode/insulator layer/source electrode, drain electrode/organic semiconductor active layer

(2) Substrate, gate electrode, insulator layer, organic semiconductor active layer, source electrode, and drain electrode

(3) Substrate/organic semiconductor active layer/source electrode, drain electrode/insulator layer/gate electrode

(4) Substrate/source electrode, drain electrode/organic semiconductor active layer/insulator layer/gate electrode

The organic field effect transistor thus configured can be used as a pixel drive conversion element of an active matrix drive type liquid crystal display or an organic electroluminescence display.

An organic thin-film solar cell has a structure in which an anode such as ITO, a hole transport layer, a photoelectric conversion layer, an electron transport layer, and a cathode are stacked on a transparent substrate such as glass. The photoelectric conversion layer has a p-type semiconductor layer on the anode side and an n-type semiconductor layer on the cathode side. The polycyclic aromatic compound of the present invention can be used as a material for a hole transport layer, a p-type semiconductor layer, an n-type semiconductor layer, and an electron transport layer, depending on the physical properties thereof. In an organic thin film solar cell, the polycyclic aromatic compound of the present invention can function as a hole transport material or an electron transport material. The organic thin-film solar cell may include not only the material but also a hole blocking layer, an electron injection layer, a hole injection layer, a smoothing layer, and the like as appropriate. In the organic thin film solar cell, known materials used in the organic thin film solar cell can be appropriately selected and used in combination.

[ examples ]

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples at all. The following are the compounds synthesized in the examples.

Synthesis example (1)

Compound (1-307): 7, 17-dichloro-5, 9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono [3,2, 1-de: synthesis of 3',2',1' -op ] pentacene

[ first stage ]

3, 5-dimethylaniline (12.5mL, 0.10mol), 3-bromotoluene (14.0mL, 0.11mol), sodium tert-butoxide (10.6g, 0.11mol), bis (dibenzylideneacetone) palladium (0) (456mg, 0.50mmol), dicyclohexyl (2',6' -dimethoxy- [1,1' -biphenyl ] -2-yl) phosphine (SPhos; 409mg, 1.0mmol) were added to toluene (500mL) under a nitrogen atmosphere at room temperature, and heated and stirred at 50 ℃ for 12 hours. The reaction solution was cooled to room temperature, and then water (500mL) was added to conduct extraction twice with toluene (300 mL). Thereafter, the mixture was washed with saturated saline (100 mL). The organic layer was recovered, and the solvent was distilled off under reduced pressure, followed by silica gel column chromatography (developing solution/hexane), whereby 3, 5-dimethyl-N- (m-tolyl) aniline (20.8g, yield 99%) was obtained as a yellow liquid.

Hexane, acetonitrile was used to wash the reaction mixture. With respect to the obtained crude product, hexane was used to stir at 60 ℃ for 3 hours, thereby obtaining 7, 17-dichloro-5, 9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono-dinaphtho [3,2, 1-de: 3',2',1' -op ] pentacene (45.7mg, 48% yield).

The structure of the obtained compound was confirmed by Nuclear Magnetic Resonance (NMR) spectroscopy.

¹H-NMR(δppm in CDCl₃,500MHz)；2.26(s,6H),2.30(s 3H),5.54(s,1H),6.57(s,1H),6.32(s,2H),6.69(s,2H),6.72(d,1H),6.85(s,1H),6.86(d,1H),7.12(t,1H)

[ second stage ]

1, 3-dibromo-5-chlorobenzene (21.6g, 80mmol), 3, 5-dimethyl-N- (m-tolyl) aniline (16.9g, 80mmol), sodium tert-butoxide (9.23g, 96mmol), bis (dibenzylideneacetone) palladium (0) (733mg, 0.80mmol), 2'-bis (diphenylphosphino) -1,1' -binaphthyl (BINAP (2,2'-bis (diphenylphosphino) -1,1' -binaphtyl); 996mg, 1.6mmol) were added to toluene (400mL) under nitrogen at room temperature, and heated and stirred at 90 ℃ for 24 hours. The reaction mixture was cooled to room temperature, and then water (400mL) was added to conduct extraction three times using toluene (200mL), followed by washing with saturated brine. The organic layer was recovered and the solvent was distilled off, and then the reaction mixture was passed through a silica gel short path column (developing solution/hexane). The solvent was distilled off, followed by drying at 100 ℃ to obtain 3-bromo-5-chloro-N- (3, 5-dimethylphenyl) -N- (m-tolyl) aniline (19.3g, yield 60%) as a white powder.

The structure of the obtained compound was confirmed by NMR spectrum.

¹H-NMR(δppm in CDCl₃,500MHz)；2.24(s,6H),2.28(s 3H),6.70(s,2H),6.76(s,1H),6.84(t,1H),6.87(m,3H),6.69(t,1H),6.99(t,1H),7.16(t,1H)

¹³C-NMR(δppm in CDCl₃,500MHz)；21.2(2C),21.2(1C),120.0(1C),122.3(1C),122.4(1C),122.7(1C),123.3(1C),123.4(2C),125.1(1C),125.9(1C),126.4(1C),129.3(1C),135.2(1C),139.3(2C),139.4(1C),146.3(1C),146.4(1C),150.4(1C)

[ third stage ]

Under nitrogen atmosphere and at room temperature, 1, 4-dibromobenzene (7.08g, 30mmol), 3, 5-dimethylaniline (9.00mL, 72mmol), sodium tert-butoxide (8.66g, 90mmol), bis (dibenzylideneacetone) palladium (0) (549mg, 0.60mmol), dicyclohexyl (2',6' -dimethoxy- [1,1' -biphenyl) were added]-2-yl) phosphine (SPhos; 493mg, 1.2mmol) was added to toluene (90mL), and the mixture was heated and stirred at 60 ℃ for 4 hours. The reaction solution was cooled to room temperature, and washed with hexane and water. Thereafter, the column was passed through a silica gel short path column (developing solution/toluene). The solvent was distilled off under reduced pressure, and then the residue was washed with hexaneWashing, thereby obtaining N in the form of white powder¹,N⁴Bis (3, 5-dimethylphenyl) benzene-1, 4-diamine (7.67g, 81% yield).

The structure of the obtained compound was confirmed by NMR spectrum.

¹H-NMR(δppm in CDCl₃,500MHz)；2.25(s,12H),5.47(s,2H),6.52(s,2H),6.61(s,4H),7.03(s,4H)

[ fourth stage ]

Under nitrogen atmosphere and at room temperature, N is reacted¹,N⁴-bis (3, 5-dimethylphenyl) benzene-1, 4-diamine (1.58g, 5.0mmol), 3-bromo-5-chloro-N- (3, 5-dimethylphenyl) -N- (m-tolyl) aniline (4.81g, 12mmol), sodium tert-butoxide (1.45g, 15mmol), bis (dibenzylideneacetone) palladium (0) (91.6mg, 0.10mmol), dicyclohexyl (2',6' -dimethoxy- [1,1' -biphenyl) ]-2-yl) phosphine (SPhos; 81.7mg, 0.20mmol) was added to toluene (15mL), and the mixture was stirred with heating at 100 ℃ for 12 hours. The reaction was cooled to room temperature and passed through a short path silica gel column (developer/toluene). The solvent was distilled off under reduced pressure, and then a silica gel column was carried out using the crude product (developing solution/hexane: toluene: 5: 1). Thereafter, washing was performed using methanol, whereby N was obtained in the form of white powder¹,N¹- (1, 4-phenylene) bis (5-chloro-N¹,N³-bis (3, 5-dimethylphenyl) -N³- (m-tolyl) benzene-1, 3-diamine) (4.63g, yield 97%).

¹H-NMR(δppm in CDCl₃,500MHz)；2.19(s,12H),2.21(s 12H),2.23(s,6H),6.49(d,4H),6.60(t,1H),6.64(m,12H),6.80(m,6H),6.86(s,4H),7.08(t,2H)

[ fifth stage ]

Under nitrogen atmosphere and at room temperature, N is reacted¹,N¹- (1, 4-phenylene) bis (5-chloro-N¹,N³-bis (3, 5-dimethylphenyl) -N³- (m-tolyl) benzene-1, 3-diamine) (95.8mg, 0.10mmol) and boron triiodide (0.314g, 0.80mmol) were added to chlorobenzene (1.0mL), and the mixture was heated and stirred at 90 ℃ for 4 hours. The reaction solution was cooled to room temperature, and then a phosphoric acid buffer solution (pH 6.8, 20mL) was added, followed by three extractions using dichloromethane (20 mL). The organic layer was recovered, and the solvent was distilled off, and then the reaction mixture was washed with hexane and acetonitrile. With respect to the obtained crude product, hexane was used to stir at 60 ℃ for 3 hours, thereby obtaining 7, 17-dichloro-5, 9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono-dinaphtho [3,2, 1-de: 3',2',1' -op ]Pentacene (45.7mg, 48% yield).

¹H-NMR(δppm in CDCl₃,500MHz)；2.33(s,6H),2.43(s 12H),2.51(s,12H),6.09(s,2H),6.32(s,2H),6.32(s,2H),6.79(d,2H),6.92(s,4H),7.14(s,4H),7.21(s,2H),7.36(2,2H),8.05(d,2H),8.32(s,2H)

Synthesis example (2)

Compound (1-313): 5,9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono-dinaphtho [3,2, 1-de: synthesis of 3',2',1' -op ] pentacene-7, 17-diamine

Reacting 7, 17-dichloro-5, 9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono [3,2, 1-de: 3',2',1' -op ] pentacene (0.292g, 0.30mmol), bis (di-tert-butyl (3-methyl 2-butenyl) phosphine) dichloropalladium (II) (18.1mg, 0.030mmol), diphenylamine (0.112mg, 0.66mmol) were added to a 10mL Schlenk tube (Schlenk flash), followed by sodium tert-butoxide (0.174g, 1.8mmol) under an argon atmosphere. Thereafter, under a nitrogen atmosphere and at room temperature, mesitylene (1.0mL) was added, and the mixture was heated and stirred at 160 ℃ for 20 hours. The reaction solution was cooled to room temperature, then the solvent was distilled off, and the obtained crude product was washed with hexane, acetonitrile. The obtained solid was recrystallized using toluene, whereby 5,9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborodinaphtho [3,2, 1-de: 3',2',1' -op ] pentacene-7, 17-diamine (0.173g, 47% yield).

¹H-NMR(δppm in CDCl₃,500MHz)；2.26(s,12H),2.27(s,6H),2.36(s,12H),5.54(s,2H),5.88(s,2H),6.51(s,2H),6.67(d,2H),6.77(s,4H),6.92(m,6H),6.98(m,12H),7.08(m,10H),8.01(d,2H),8.25(s,2H)

Synthesis example (3)

Compound (1-321): 7, 17-bis (9H-carbazol-9-yl) -5,9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono [3,2, 1-de: synthesis of 3',2',1' -op ] pentacene

Reacting 7, 17-dichloro-5, 9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono [3,2, 1-de: 3',2',1'-op ] pentacene (0.292g, 0.30mmol), bis (di-tert-butyl (3-methyl 2-butenyl) phosphine) dichloropalladium (II) (18.1mg, 0.030mmol), carbazole (0.111mg, 0.66mmol) were added to a 10mL Schlenk's tube, followed by sodium tert-butoxide (0.174g, 1.8mmol) under an argon atmosphere. Thereafter, under a nitrogen atmosphere and at room temperature, mesitylene (1.0mL) was added, and the mixture was heated and stirred at 160 ℃ for 20 hours. The reaction solution was cooled to room temperature, then the solvent was distilled off, and the obtained crude product was washed with hexane, acetonitrile. The obtained solid was recrystallized using o-dichlorobenzene, whereby 7, 17-bis (9H-carbazol-9-yl) -5,9,15, 19-tetrakis (3, 5-dimethylphenyl) -3, 13-dimethyl-5, 9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diboranedinaphtho [3,2, 1-de: 3',2',1' -op ] pentacene (0.241g, 58% yield).

¹H-NMR(δppm in CDCl₃,500MHz)；2.35(s,6H),2.38(s,12H),2.49(s,12H),6.29(s,2H),6.55(s,2H),6.68(s,2H),6.81(d,2H),7.02(s,4H),7.07(s,2H),7.17(m,8H),7.25(m,12H),7.42(m,8H),8.02(d,4H),8.18(d,2H),8.51(s,2H)

Synthesis example (4)

Compound (1-331): 3, 13-di-tert-butyl-7, 17-dichloro-5, 15-bis (3, 5-di-tert-butylphenyl) -9, 19-bis (3, 5-dimethylphenyl) -5,9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono-dinaphtho [3,2, 1-de: 3',2',1' -op ] pentacene

Will N¹,N¹- (1, 4-phenylene) bis (N8- (3- (tert-butyl) phenyl) -5-chloro- (N8- (3, 5-di-tert-butylphenyl) -N1(3, 5-dimethylphenyl) benzene-1, 3-diamine)) (0.362g, 0.30mmol) was charged into a 10mL schlenk tube, followed by boron triiodide (0.475g, 1.2mmol) under an argon atmosphere. Thereafter, chlorobenzene (1.0mL) was added under a nitrogen atmosphere at room temperature, and heating and stirring were performed at 80 ℃ for 20 hours. The reaction solution was cooled to room temperature, and then a phosphoric acid buffer solution (pH 6.8, 20mL) was added, followed by three extractions using toluene (20 mL). The organic layer was recovered, the solvent was distilled off, and then the obtained crude product was washed with hexane and acetonitrile, whereby 3, 13-di-tert-butyl-7, 17-dichloro-5, 15-bis (3, 5-di-tert-butylphenyl) -9, 19-bis (3, 5-dimethylphenyl) was obtained as a vermilion powder) -5,9,15, 19-tetrahydro-5, 9,15, 19-tetraaza-10 b,20 b-diborono [3,2, 1-de: 3',2',1' -op]Pentacene (0.199g, 54% yield).

¹H-NMR(δppm in CDCl₃,500MHz)；1.20(s,18H),1.37(s,36H),2.52(s,12H),6.22(s,2H)6.35(s,2H),6.63(s,2H),7.04(s,2H),7.17(s,8H),7.36(s,2H),7.63(s,2H),8.13(s,2H),8.35(s,2H)

The other compounds of the present invention can be synthesized by appropriately changing the compounds of the starting materials and using the method according to the synthesis example.

Next, the evaluation of the basic properties of the compound of the present invention and the production and evaluation of an organic EL device using the compound of the present invention will be described.

< evaluation of basic physical Properties >

Preparation of samples

In the case of evaluating the absorption characteristics and the light emission characteristics (fluorescence and phosphorescence) of the compound to be evaluated, there are cases where the compound to be evaluated is dissolved in a solvent and evaluated in the solvent, and cases where the compound to be evaluated is evaluated in a thin film state. Further, when the evaluation is performed in a thin film state, there are cases where only the compound to be evaluated is made thin and the evaluation is performed, and cases where the compound to be evaluated is dispersed in an appropriate matrix material and made thin and the evaluation is performed, depending on the form of use of the compound to be evaluated in the organic EL device.

As the matrix material, commercially available polymethyl methacrylate (PMMA) or the like can be used. Film samples dispersed in PMMA can be made, for example, as follows: PMMA and the compound to be evaluated were dissolved in toluene, and then a thin film was formed on a transparent support substrate (10 mm. times.10 mm) made of quartz by a spin coating method.

In addition, a method for producing a film sample when the host material is the matrix material is described below. Mixing quartz transparent supporting substrate (10mm × 10mm × 1.0mm)A molybdenum vapor deposition boat containing a host material and a molybdenum vapor deposition boat containing a dopant material were attached to a substrate holder fixed to a commercially available vapor deposition apparatus (manufactured by showa vacuum (jet)). Then, the vacuum vessel was depressurized to 5X 10^-4Pa, the evaporation boat containing the host material and the evaporation boat containing the dopant material are heated at the same time, and evaporation is performed so as to have an appropriate film thickness, thereby forming a mixed thin film of the host material and the dopant material. The deposition rate is controlled according to the set mass ratio of the host material to the dopant material.

Evaluation of absorption characteristics and light emission characteristics

The absorption spectrum of the sample was measured using an ultraviolet-visible near-infrared spectrophotometer (Shimadzu corporation, UV-2600). The measurement of the fluorescence spectrum or phosphorescence spectrum of the sample was performed using a spectrofluorometer (manufactured by Hitachi high-tech (Kagaku Co., Ltd.); F-7000).

For measurement of fluorescence spectrum, photoluminescence (photoluminescence) was measured by excitation at an appropriate excitation wavelength at room temperature. For the measurement of phosphorescence spectrum, the measurement was performed in a state where the sample was immersed in liquid nitrogen (temperature 77K) using an attached cooling unit. In order to observe the phosphorescence spectrum, a light chopper (optical chopper) was used to adjust the delay time from the irradiation of the excitation light to the start of the measurement.

Evaluation of basic physical Properties of Compounds (1-307)

[ absorption characteristics ]

Preparation of Compound (1-307) at 2.0X 10^-5The sample obtained by dissolving the concentration of M in toluene was subjected to absorption spectrum measurement (FIG. 3). As a result, the maximum absorption wavelength was 522nm in the visible light region.

[ luminescence characteristics ]

For measurement of fluorescence spectrum, compounds (1-307) were prepared at 2.0X 10^-5A sample obtained by dissolving the concentration of M in toluene was excited at an excitation wavelength of 470nm to measure photoluminescence (FIG. 3). As a result, the maximum emission wavelength was 533nm, the half-value width was 18nm, and the chromaticity was CIE chromaticity (x, y) ═ 0.314,0.666). In addition, the same solution was prepared, and the fluorescence quantum yield was measured by excitation at an excitation wavelength of 470nm, and as a result, it was as high as 94.5%.

Evaluation of basic physical Properties of Compound (1-313)

[ absorption characteristics ]

Preparation of Compound (1-313) at 2.0X 10^-5The sample obtained by dissolving the concentration of M in toluene was subjected to absorption spectrum measurement (FIG. 4). As a result, the maximum absorption wavelength was 528nm in the visible light region.

[ luminescence characteristics ]

For measurement of fluorescence spectrum, compound (1-313) was prepared at 2.0X 10^-5A sample obtained by dissolving the concentration of M in toluene was excited at an excitation wavelength of 470nm to measure photoluminescence (FIG. 4). As a result, the maximum emission wavelength was 541nm, the half-value width was 21nm, and the chromaticity was CIE chromaticity (x, y) ═ 0.347, 0.642. In addition, the same solution was prepared, and the fluorescence quantum yield was measured by excitation at an excitation wavelength of 470nm, and as a result, it was as high as 98.7%.

Evaluation of basic physical Properties of Compound (1-321)

[ absorption characteristics ]

Preparation of Compound (1-321) at 2.0X 10^-5The sample obtained by dissolving the concentration of M in toluene was subjected to absorption spectrum measurement (FIG. 5). As a result, the maximum absorption wavelength was 530nm in the visible light region.

[ luminescence characteristics ]

For measurement of fluorescence spectrum, preparation was made for compound (1-321) at 2.0X 10^-5A sample obtained by dissolving the concentration of M in toluene was excited at an excitation wavelength of 470nm to measure photoluminescence (FIG. 5). As a result, the maximum emission wavelength was 542nm, the half-value width was 18nm, and the chromaticity was CIE chromaticity (x, y) ═ 0.362, 0.628. In addition, the same solution was prepared, and the fluorescence quantum yield was measured by excitation at an excitation wavelength of 470nm, and found to be 78.4%.

Evaluation of basic Properties of comparative Compound 1(C545T)

Compound (C545T) was purchased from optoelectronics (Lumtec) corporation (taiwan) and used without purification.

[ absorption characteristics ]

Preparation of Compound (C545T) at 2.0X 10^-5The sample obtained by dissolving the concentration of M in toluene was subjected to absorption spectrum measurement. As a result, the maximum absorption wavelength was 473nm in the visible light region.

[ luminescence characteristics ]

For the measurement of fluorescence spectrum, compound (C545T) was prepared at 2.0X 10 ^-5A sample obtained by dissolving the concentration of M in toluene was excited at an excitation wavelength of 470nm to measure photoluminescence. As a result, the maximum emission wavelength was 506nm, and the half-value width was 58 nm.

Evaluation of basic Properties of comparative Compound 2(BA-NPB)

The compound (BA-NPB) was purchased from the company Lumtec (Lumtec) in Taiwan and used without purification.

[ absorption characteristics ]

Preparation of Compound (BA-NPB) at 2.0X 10^-5The sample obtained by dissolving the concentration of M in toluene was subjected to absorption spectrum measurement. As a result, the maximum absorption wavelength was 441nm in the visible light region.

[ luminescence characteristics ]

For measurement of fluorescence spectrum, compound (BA-NPB) was prepared at 2.0X 10^-5A sample obtained by dissolving the concentration of M in toluene was excited at an excitation wavelength of 441nm to measure photoluminescence. As a result, the maximum emission wavelength was 517nm, and the half-value width was 57 nm.

Comparative Compound 3(Ir (ppy)₃) Evaluation of basic Properties of

Compound (Ir (ppy)₃) Purchased from the company Lumtec (Taiwan), and used without purification.

[ absorption characteristics ]

Preparation of Compound (Ir (ppy)₃) At 2.0 × 10^-5The sample obtained by dissolving the concentration of M in toluene was subjected to absorption spectrum measurement. As a result, the maximum absorption wavelength was 350nm in the visible light region.

[ luminescence characteristics ]

For measurement of phosphorescence spectrum, a compound (Ir (ppy)₃) At 2.0 × 10^-5A sample obtained by dissolving the concentration of M in toluene was excited at an excitation wavelength of 230nm to measure photoluminescence. As a result, the maximum emission wavelength was 517nm, and the half-value width was 66 nm.

Production of organic EL element

Organic EL devices of examples and comparative examples were prepared, and current density, luminance, chromaticity, external quantum efficiency, and the like were measured by applying a voltage.

[ Table 1]

(constitution of organic EL element A)

In table 1, "HI 1" is N, N '-diphenyl-N, N' -dinaphthyl-4, 4 '-diaminobiphenyl, "HT 1" is 4,4',4 ″ -tris (N-carbazolyl) triphenylamine, "EB 1" is 1, 3-bis (N-carbazolyl) benzene, "EMH 1" is 3,3 '-bis (N-carbazolyl) -1,1' -biphenyl, "ET 1" is diphenyl [4- (triphenylsilyl) phenyl ] phosphine oxide.

In table 1, "AD 1" is 2, 5-bis- (4- (10H-phenoxazin-10-yl) phenyl) -1,3, 4-oxadiazole and "AD 2" is 3, 6-bis- (dibenzo [ b, d ] furan-2-yl) -9- (4- (4, 6-diphenyl-1, 3, 5-triazin-2-yl) phenyl) -9H-carbazole, chemical structures are shown below along with "AD 1", "AD 2" and "comparative compound 1".

< example 1 >

< constitution A: element > (1-307) with EMH1 as host compound, AD1 as assist dopant, and compound (1-307) as emissive dopant

A glass substrate (manufactured by Opto Science) having a thickness of 200nm formed by sputtering and having a thickness of 26mm by 28mm by 0.7mm polished to 50nm was used as a transparent support substrate. The transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by the changzhou industry), and a boat for tantalum vapor deposition was set in which HI1, HT1, EB1, EMH1, AD1, compounds (1 to 307), and ET1 were placed; aluminum nitride evaporation boats containing LiF and aluminum were placed therein, respectively.

The following layers were sequentially deposited on the ITO film of the transparent support substrate. The vacuum vessel was depressurized to 5X 10^-4Pa, HI1 was heated first to perform vapor deposition so that the film thickness became 40nm, and HT1 was heated to perform vapor deposition so that the film thickness became 15nm, thereby forming a hole injection transport layer including two layers. Subsequently, EB1 was heated to form an electron blocking layer by vapor deposition so that the film thickness became 15 nm. Next, EMH1 as a host, AD1 as an auxiliary dopant, and the compound (1-307) as an emitting dopant were heated at the same time, and co-evaporation was performed so that the film thickness became 20nm to form a light-emitting layer. The deposition rate was adjusted so that the mass ratio of the host, the auxiliary dopant, and the emissive dopant became approximately 90 to 9 to 1. Subsequently, ET1 was heated and vapor-deposited to 30nm to form an electron transport layer. The deposition rate of each layer is set to 0.01nm/sec to 1 nm/sec. Then, LiF was heated to be deposited at a deposition rate of 0.01nm/sec to 0.1nm/sec so that the film thickness became 1nm, and aluminum was heated to be deposited to be 100nm so that the cathode was formed, thereby obtaining an organic EL element. In this case, the deposition rate of aluminum is adjusted to 1nm to 10 nm.

A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 522nm and the half-value width was 18nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 26.0% and was high.

< comparative example 1 >

< constitution A: element without emissive dopant and with auxiliary dopant AD1

Without using an emissive dopant andan EL element was obtained by the same steps and configuration as in example 1, except that the mass ratio of the host to the auxiliary dopant was changed to 90 to 10. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 522nm and the half-value width was 72nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 10.2%, and was low quantum efficiency.

< comparative example 2 >

< constitution A: element > (in the case of the host compound EMH1, the assist dopant AD1, and the emissive dopant) of comparative compound 1

An EL element was obtained by the same procedure and composition as in example 1, except that the emitting dopant was changed to comparative compound 1. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 520nm and the half-value width was 55nm, and green emission was observed.

< example 2 >

< constitution A: element > (1-307) with EMH1 as host compound, AD2 as assist dopant, and compound (1-307) as emissive dopant

An EL element was obtained by the same steps and configuration as in example 1, except that the auxiliary dopant was changed to AD 2. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 522nm and the half-value width was 18nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 24.0%, and was high quantum efficiency.

< comparative example 3 >

< constitution A: element without emissive dopant and with auxiliary dopant AD2

Without using emissive dopants and by combining the host with auxiliary dopantsAn EL element was obtained by the same steps and configuration as in example 2, except that the mass ratio of (a) was changed to 90 to 10. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of emission, the peak wavelength was 528nm and the half-value width was 60nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 9.8%, and was low quantum efficiency.

[ Table 2]

(constitution of organic EL element B)

In Table 2, "HI 2" is N⁴,N⁴' -Diphenyl-N⁴,N⁴'-bis (9-phenyl-9H-carbazol-3-yl) - [1,1' -biphenyl]-4,4 '-diamine, "HAT-CN" is 1,4,5,8,9, 12-hexaazatriphenylhexacarbonitrile, "HT 2" is N- ([1,1' -biphenyl]-4-yl) -9, 9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine, "HT 3" is N, N-bis (4- (dibenzo [ b, d ] s]Furan-4-yl) phenyl) - [1, 1': 4', 1' -terphenyl]-4-amine, "EMH 2" is 1,8, 10-tris ([1,1' -biphenyl)]-4-yl) anthracene, ET2 being 4,6,8, 10-tetraphenyl [1,4 ]]Benzoxaborole heterocyclohexeno [2,3,4-k1]Phenoxyboron heterocyclohexene, "ET 3," is 3,3' - ((2-phenylanthracene-9, 10-diyl) bis (4, 1-phenylene)) bis (4-methylpyridine), the chemical structures of which are shown below together with "Liq", "comparative compound 1" and "comparative compound 2".

< example 3 >

< constitution B: element using compound (1-307) as dopant and EMH2 as host

A glass substrate (manufactured by Opto Science) having a thickness of 200nm formed by sputtering and having a thickness of 26mm by 28mm by 0.7mm polished to 120nm was used as a transparent support substrate. The transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by the chan industries, inc.), and a boat for tantalum vapor deposition was set in which HI2, HT2, HAT-CN, EB2, EMH2, compounds (1-307), Liq, ET2, and ET3 were placed, respectively; aluminum nitride evaporation boats containing LiF and aluminum were placed therein, respectively.

The following layers are sequentially formed on the ITO film of the transparent support substrate. The vacuum vessel was depressurized to 5X 10^-4Pa, HI2 was heated to form a film of 40nm, and then HAT-CN was heated to form a film of 5nm, thereby forming a hole injection layer. Next, HT2 was heated to perform vapor deposition so that the film thickness became 15nm, and HT3 was heated to perform vapor deposition so that the film thickness became 10nm, thereby forming a hole transport layer. Next, EMH2 as a host and compounds (1 to 307) as dopants were simultaneously heated, and co-evaporation was performed so that the film thickness became 25nm, thereby forming a light-emitting layer. The deposition rate was adjusted so that the mass ratio of the host to the dopant became approximately 98 to 2. Then, ET2 was heated to 5nm and vapor-deposited, and ET3 was simultaneously heated with Liq to 25nm in thickness and co-vapor-deposited to form an electron transport layer. The deposition rate was adjusted so that the mass ratio of ET3 and Liq became 50 to 50. The deposition rate of each layer is set to 0.01nm/sec to 1 nm/sec. Subsequently, Liq was heated to perform vapor deposition at a vapor deposition rate of 0.01nm/sec to 0.1nm/sec so that the film thickness became 1nm, and then magnesium and silver were simultaneously heated to perform vapor deposition so that the film thickness became 100nm, thereby forming a cathode, thereby obtaining an organic EL element. At this time, the deposition rate was adjusted so that the mass ratio of magnesium to silver became 90 to 10, and the deposition rate was adjusted so as to become 1nm to 1 nm.

A dc voltage was applied with the ITO electrode as an anode and the magnesium silver electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 522nm and the half-value width was 17nm, and green emission was observed. In addition, 1000cd/m²External quantum efficiency in light emission is7.0 percent. In particular, the half-value width of the emission spectrum is small and deep green can be achieved.

< example 4 >

< constitution B: element using compound (1-313) as dopant

An EL element was obtained by the same steps and composition as in example 3, except that the dopant was changed. As a result, 1000cd/m²The external quantum efficiency in light emission was 7.2%, and the maximum emission wavelength in the emission spectrum was 518nm and the half-value width was 20 nm. In particular, the half-value width of the emission spectrum is small and deep green can be achieved.

< example 5 >

< constitution B: element using compound (1-321) as dopant

An EL element was obtained by the same steps and composition as in example 3, except that the dopant was changed. As a result, 1000cd/m²The external quantum efficiency in light emission was 6.8%, and the maximum emission wavelength in the emission spectrum was 532nm, and the half-value width was 19 nm. In particular, the half-value width of the emission spectrum is small and deep green can be achieved.

< comparative example 4 >

< constitution B: element with comparative compound 1 as dopant

An EL element was obtained by the same steps and composition as in example 3, except that the dopant was changed. As a result, 1000cd/m²The external quantum efficiency in light emission was 6.6%, and in the emission spectrum, the maximum emission wavelength was 518nm and the half-value width was 60 nm. As compared with the compound (1-313), the following results were obtained: the external quantum efficiency is equal, but the half-value width is wide.

< comparative example 5 >

< constitution B: element with comparative compound 2 as dopant

An EL element was obtained by the same steps and composition as in example 3, except that the dopant was changed. As a result, 1000cd/m²The external quantum efficiency in light emission was 6.8%, and the maximum emission wavelength in the emission spectrum was 527nm and the half-value width was 58 nm. As compared with the compound (1-321), the following results were obtained: external quantum efficiency parityBut wide at half-value width.

[ Table 3]

(constitution of organic EL element A)

In table 3, chemical structures are shown below together with "AD 3", "AD 4", "AD 5", "AD 6", "AD 7", "AD 8", "EMH 3", "EMH 4", and "EMH 5".

< example 6 >

< constitution A: element >, in which EMH1 is the host compound, AD3 is the auxiliary dopant, and compound (1-313) is the emissive dopant

A glass substrate (manufactured by Opto Science) having a thickness of 200nm formed by sputtering and having a thickness of 26mm by 28mm by 0.7mm polished to 50nm was used as a transparent support substrate. The transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by the changzhou industry), and a boat for tantalum vapor deposition was set in which HI1, HT1, EB1, EMH1, AD3, compounds (1-313), and ET1 were placed; aluminum nitride evaporation boats containing LiF and aluminum were placed therein, respectively.

The following layers were sequentially deposited on the ITO film of the transparent support substrate. The vacuum vessel was depressurized to 5X 10^-4Pa, HI1 was heated first to perform vapor deposition so that the film thickness became 40nm, and HT1 was heated to perform vapor deposition so that the film thickness became 15nm, thereby forming a hole injection transport layer including two layers. Subsequently, EB1 was heated to form an electron blocking layer by vapor deposition so that the film thickness became 15 nm. Next, EMH1 as a host, AD3 as an auxiliary dopant, and the compound (1-313) as an emitting dopant were heated at the same time, and co-evaporation was performed so that the film thickness became 20nm, thereby forming a light-emitting layer. With a host, an auxiliary dopant and an emissive dopant The deposition rate was adjusted so that the mass ratio of (1) to (9) was approximately 90 to 1. Subsequently, ET1 was heated and vapor-deposited to 30nm to form an electron transport layer. The deposition rate of each layer is set to 0.01nm/sec to 1 nm/sec. Then, LiF was heated to be deposited at a deposition rate of 0.01nm/sec to 0.1nm/sec so that the film thickness became 1nm, and aluminum was heated to be deposited to be 100nm so that the cathode was formed, thereby obtaining an organic EL element. In this case, the deposition rate of aluminum is adjusted to 1nm to 10 nm.

A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 520nm and the half-value width was 19nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 27.0%, and was high quantum efficiency.

< example 7 >

< constitution A: element >, in which EMH1 is the host compound, AD4 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same steps and composition as in example 6, except that the auxiliary dopant was changed to AD 4. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m ²In the emission spectrum at the time of light emission, the peak wavelength was 522nm and the half-value width was 20nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 24.4% and was high.

< example 8 >

< constitution A: element >, in which EMH1 is the host compound, AD5 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same steps and composition as in example 6, except that the auxiliary dopant was changed to AD 5. A DC voltage was applied to the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity and color were measuredExternal quantum efficiency. 100cd/m²In the emission spectrum at the time of emission, the peak wavelength was 518nm and the half-value width was 17nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 22.3%, and was high quantum efficiency.

< example 9 >

< constitution A: element >, in which EMH1 is the host compound, AD6 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same steps and composition as in example 6, except that the auxiliary dopant was changed to AD 6. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m ²In the emission spectrum at the time of emission, the peak wavelength was 524nm and the half-value width was 22nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 23.5%, and was high quantum efficiency.

< example 10 >

< constitution A: element >, in which EMH1 is the host compound, AD7 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same steps and composition as in example 6, except that the auxiliary dopant was changed to AD 7. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of emission, the peak wavelength was 525nm and the half-value width was 24nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 22.0% and was high.

< example 11 >

< constitution A: element >, in which EMH1 is the host compound, AD8 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same steps and composition as in example 6, except that the auxiliary dopant was changed to AD 8. ITO electrode as anode and aluminum electrode as cathode Dc voltage was applied to the electrodes, and luminance, chromaticity and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of emission, the peak wavelength was 520nm and the half-value width was 20nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 22.6% and was high.

< example 12 >

< constitution A: element >, in which EMH3 is the host compound, AD3 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same procedure and composition as in example 6, except that the host compound was changed to EMH 3. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 523nm and the half-value width was 25nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 19.0% and was high.

< example 13 >

< constitution A: element >, in which EMH4 is the host compound, AD3 is the auxiliary dopant, and compound (1-313) is the emissive dopant

An EL element was obtained by the same procedure and composition as in example 6, except that the host compound was changed to EMH 4. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m ²In the emission spectrum at the time of light emission, the peak wavelength was 523nm and the half-value width was 22nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 23.2%, and was high quantum efficiency.

< example 14 >

< constitution A: element >, in which EMH5 is the host compound, AD3 is the auxiliary dopant, and compound (1-313) is the emissive dopant

E was obtained through the same steps and composition as in example 6, except that the host compound was changed to EMH5And an L element. A dc voltage was applied with the ITO electrode as an anode and the aluminum electrode as a cathode, and the luminance, chromaticity, and external quantum efficiency were measured. 100cd/m²In the emission spectrum at the time of light emission, the peak wavelength was 519nm and the half-value width was 19nm, and green emission was observed. Further, 100cd/m²The external quantum efficiency in light emission was 22.0% and was high.

As described above, the inventive compound can realize high-efficiency green light emission with a very narrow half-value width by using an auxiliary dopant. When applied to a display, the phosphor can emit green light with high efficiency and high color purity. As an embodiment of the present invention, an embodiment using an auxiliary dopant is described, and for example, an Advanced Materials (adv.mater.) 2020,1906614-excited complex (exiplex) body reported by ada and midebu, et al, of kyushu university may be used instead of the auxiliary dopant.

Production and evaluation of coating-type (light-emitting layer) organic EL element

< synthetic examples: macromolecular host compound: synthesis of SPH-101

SPH-101 was synthesized according to the method described in International publication No. 2015/008851. Copolymers were obtained in which M2 or M3 was bonded adjacent to M1, the units being, depending on the input ratio, 50: 26: 24 (molar ratio).

Wherein Me is a methyl group, Bpin is a pinacolato boron group, and represents a bonding position of each unit. In addition, the terminal bonds to hydrogen or aryl.

< synthetic examples: high molecular hole transport compound: synthesis of XLP-101

XLP-101 was synthesized according to the method described in Japanese patent laid-open publication No. 2018-61028. A copolymer having M4, M5 and M6 bonded thereto was obtained. The units are 40: 10: 50 (molar ratio).

Wherein Bpin is a pinacolato boron group, and indicates a bonding position of each unit. In addition, the terminal bonds to hydrogen or aryl. < preparation of XLP-101 solution >

XLP-101 was dissolved in xylene to prepare a 0.6 wt% XLP-101 solution.

< preparation of composition for Forming light-emitting layer >

The composition for forming a light-emitting layer of example F-1 was prepared. The compounds used in the preparation of the compositions are shown below.

< example F-1 >

The following components were stirred until a homogeneous solution was obtained to prepare a composition for forming a light-emitting layer.

The prepared composition for forming a light-emitting layer was spin-coated on a glass substrate, and dried by heating under reduced pressure, whereby a coating film free from film defects and excellent in smoothness was obtained.

< manufacture of organic EL element >

A method for producing an organic EL element using a crosslinkable hole-transporting material is shown in examples S-1 and S-2, and a method for producing an organic EL element using an orthogonal solvent system is shown in example S-3. The material composition of each layer in the organic EL device thus produced is shown in table 4.

[ Table 4]

"PEDOT" in table 4 is shown below: PSS "," OTPD "," PCz "," ET4 ".

< PEDOT: PSS solution >

Commercially available PEDOT was used: PSS solution (Clevios (TM) P VP AI4083, aqueous dispersion of PEDOT: PSS, manufactured by Heraeus Holdings).

< preparation of OTPD solution >

OTPD (LT-N159, manufactured by Luminescence Technology Corp) and IK-2 (photo cation polymerization initiator, manufactured by Sanapro) were dissolved in toluene to prepare an OTPD solution having an OTPD concentration of 0.7 wt% and an IK-2 concentration of 0.007 wt%.

< preparation of PCz solution

PCz (polyvinylcarbazole) was dissolved in dichlorobenzene to prepare a 0.7 wt% PCz solution.

< example S-1 >

Spin-coating PEDOT: the PSS solution was calcined on a hot plate at 200 ℃ for 1 hour to obtain a film thickness of 40nm of PEDOT: PSS film (hole injection layer). The OTPD solution was then spin coated and dried on a hot plate at 80 ℃ for 10 minutes. Using an exposure machine to expose the substrate at an intensity of 100mJ/cm²Exposure was performed, and the film was calcined on a hot plate at 100 ℃ for 1 hour, thereby producing an OTPD film (hole transport layer) having a film thickness of 30nm, which was insoluble in the solution. Subsequently, the composition for forming a light-emitting layer of example F-1 was spin-coated and calcined on a heating plate at 120 ℃ for 1 hour to prepare a light-emitting layer having a thickness of 20 nm.

The multilayer film thus produced was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by showa vacuum (jet)), and a molybdenum vapor deposition boat containing ET1, a molybdenum vapor deposition boat containing LiF, and a tungsten vapor deposition boat containing aluminum were installed therein. The vacuum vessel was depressurized to 5X 10^-4Pa, then, the boat for vapor deposition in which ET1 was placed was heated to a film thickness of 30nmThe electron transport layer is formed by evaporation. The deposition rate in forming the electron transport layer was set to 1 nm/sec. Thereafter, the boat for vapor deposition containing LiF was heated, and vapor deposition was performed at a vapor deposition rate of 0.01nm/sec to 0.1nm/sec so that the film thickness became 1 nm. Then, the boat containing aluminum was heated to form a cathode by vapor deposition so that the thickness of the cathode became 100 nm. An organic EL element was obtained in the manner described.

< example S-2 >

Spin-coating PEDOT: the PSS solution was calcined on a hot plate at 200 ℃ for 1 hour to obtain a film thickness of 40nm of PEDOT: PSS film (hole injection layer). Then, the solution of XLP-101 was spin-coated, dried on a hot plate at 80 ℃ for 10 minutes, and then calcined on a hot plate at 180 ℃ for 1 hour, thereby producing an XLP-101 film (hole transport layer) insoluble in the solution and having a film thickness of 30 nm. Subsequently, the composition for forming a light-emitting layer of example F-1 was spin-coated and calcined on a heating plate at 120 ℃ for 1 hour to prepare a light-emitting layer having a thickness of 20 nm.

An electron transport layer and a cathode were formed by the same procedure as in example S-1 using the multilayer film thus produced, thereby obtaining an organic EL device.

< example S-3 >

Spin-coating PEDOT: the PSS solution was calcined on a hot plate at 200 ℃ for 1 hour to obtain a film thickness of 40nm of PEDOT: PSS film (hole injection layer). Then, the PCz solution was spin-coated, dried on a hot plate at 80 ℃ for 10 minutes, and then calcined on a hot plate at 100 ℃ for 1 hour, thereby forming a PCz film (hole transport layer) having a film thickness of 30nm, which was insoluble in the composition for forming a light-emitting layer. Subsequently, the composition for forming a light-emitting layer of example F-1 was spin-coated and calcined on a heating plate at 120 ℃ for 1 hour to prepare a light-emitting layer having a thickness of 20 nm.

[ industrial applicability ]

In the present invention, by providing a novel polycyclic aromatic compound, the selection of materials for organic EL elements can be increased. Further, by using a novel polycyclic aromatic compound as a material for an organic electroluminescent element, an excellent organic EL element, a display device including the organic EL element, a lighting device including the organic EL element, and the like can be provided.

Claims

1. A polycyclic aromatic compound represented by the following formula (1);

in the formula (1), the reaction mixture is,

R¹and R²Independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a heteroaryl group having 2 to 15 carbon atoms, a diarylamino group in which the aryl group is an aryl group having 6 to 12 carbon atoms, a cyano group or a halogen,

is selected from the group consisting of aryl ring and heteroaryl ring in the compound represented by the formula (1)At least one of which may be condensed with at least one cycloalkane, at least one of which may be substituted for hydrogen, at least one-CH of which₂-may be substituted by-O-,

2. The polycyclic aromatic compound according to claim 1,

ring A is substituted by Z¹Aryl ring of (a) or having one substituent Z¹Or a heteroaryl ring having one substituent Z¹Aryl ring of (a) or having one substituent Z¹Z in the heteroaryl ring of (1)¹Bound to Z by a single bond or a linking group ¹The structure of the aryl or heteroaryl ring to which it is bonded,

Z¹and Z²Each independently is any one of the following groups:

diarylamino groups which may be substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, aryloxy, alkyl-substituted silyl, cyano or halogen, two aryl groups may be bonded to each other;

a cyano group; or

The halogen(s) are selected from the group consisting of,

R¹and R²Each independently hydrogen, cyano or halogen.

3. The polycyclic aromatic compound according to claim 1, which is represented by the following formula (2);

in the formula (2), the reaction mixture is,

substituent group X:

diarylamino groups which may be substituted by aryl, heteroaryl, cycloalkyl, alkyl, cyano or halogen, two aryl groups may be bonded to each other;

a cyano group; and

the halogen(s) are selected from the group consisting of,

said > N-R and said > CR₂R of (A) may be bonded to the a-ring, the b-ring, the c-ring and/or the d-ring through a linking group or a single bond,

R¹and R²Independently represents hydrogen, alkyl group having 1 to 6 carbon atoms, aryl group having 6 to 12 carbon atoms, cyano group or halogen,

Z¹and Z²Each independently is any one of the following groups:

a cyano group; or

The halogen(s) are selected from the group consisting of,

4. The polycyclic aromatic compound of claim 3, wherein X¹、X²、X³And X⁴At least one of (a) is > N-R.

5. The polycyclic aromatic compound according to claim 3 or 4, wherein R > N-R is an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms which may be substituted with a cyano group or a halogen, or an alkyl group having 1 to 4 carbon atoms which may be substituted with a cyano group or a halogen.

6. The polycyclic aromatic compound according to any one of claims 3 to 5, wherein R ¹And R²Are all hydrogen.

7. The polycyclic aromatic compound according to any one of claims 3 to 6, wherein R³、R⁴、R⁸And R⁹Are all hydrogen.

8. The polycyclic aromatic compound according to any one of claims 3 to 6, wherein X¹、X²、X³And X⁴Are all more than N-R,

Z¹and Z²Are diarylamino groups which may be substituted by aryl, heteroaryl, alkyl-substituted silyl, cyano or halogen,

Z¹and X¹Or X²R of > N-R as R³Or R⁴Boron of (b) is a linking group to bond with the a ring,

9. The polycyclic aromatic compound of any one of claims 3 to 8, wherein R⁵、R⁶、R⁷、R¹⁰、R¹¹And R¹²Independently hydrogen, aryl group having 6 to 10 carbon atoms which may be substituted with cyano or halogen, cycloalkyl group having 3 to 12 carbon atoms which may be substituted with cyano or halogen, or alkyl group having 1 to 6 carbon atoms which may be substituted with cyano or halogen.

10. The polycyclic aromatic compound of claim 1, which is represented by formula (1-307), formula (1-313), formula (1-321) or formula (1-331);

in the formula, Me is methyl, and tBu is tert-butyl.

11. A green light emitting material containing the polycyclic aromatic compound according to any one of claims 1 to 10.

12. A material for organic devices, comprising the polycyclic aromatic compound according to any one of claims 1 to 10.

13. The material for organic devices according to claim 12, wherein the material for organic devices is a material for organic electroluminescent elements, a material for organic field effect transistors, or a material for organic thin-film solar cells.

14. A material for a light-emitting layer, which contains the polycyclic aromatic compound according to any one of claims 1 to 10 and is used for forming a light-emitting layer of an organic electroluminescent element.

15. An organic electroluminescent element comprising: a pair of electrodes including an anode and a cathode; and a light-emitting layer which is arranged between the pair of electrodes and contains the material for a light-emitting layer according to claim 14.

16. The organic electroluminescent element according to claim 15, wherein the light-emitting layer further contains at least one compound selected from the group consisting of a compound represented by the following formula (3), a compound represented by the following formula (4), and a compound represented by the following formula (5);

In the formula (3), L¹Is an arylene group having 6 to 24 carbon atoms,

at least one hydrogen in the compound represented by the above formula may be substituted by an alkyl group having 1 to 6 carbon atoms, a cyano group, a halogen or deuterium.

17. The organic electroluminescent element according to claim 15 or 16, which comprises an electron transport layer and/or an electron injection layer disposed between the cathode and the light-emitting layer, wherein at least one of the electron transport layer and the electron injection layer contains at least one selected from the group consisting of borane derivatives, pyridine derivatives, fluoranthene derivatives, BO derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, arylnitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, hydroxyquinoline metal complexes, thiazole derivatives, benzothiazole derivatives, silole derivatives and oxazoline derivatives.

18. The organic electroluminescent element according to claim 17, wherein the electron transport layer and/or the electron injection layer further contains at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, oxides of alkali metals, halides of alkali metals, oxides of alkaline earth metals, halides of alkaline earth metals, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals, and organic complexes of rare earth metals.

19. A display device comprising the organic electroluminescent element as claimed in any one of claims 15 to 18.

20. A lighting device comprising the organic electroluminescent element as claimed in any one of claims 15 to 18.