CN112010883A

CN112010883A - Polycyclic aromatic compound, material for organic device, organic electroluminescent element, display device, and lighting device

Info

Publication number: CN112010883A
Application number: CN202010457204.3A
Authority: CN
Inventors: 畠山琢次; 川角亮介; 增田胜也
Original assignee: Kansai College; JNC Corp
Current assignee: Kansai College; SK Materials JNC Co Ltd
Priority date: 2019-05-29
Filing date: 2020-05-26
Publication date: 2020-12-01
Also published as: KR20200138023A; JP2020196700A

Abstract

The present invention relates to a polycyclic aromatic compound in which a nitrogen-containing substituent represented by formula (BiN) is introduced into a polycyclic aromatic compound represented by formula (1) in which a plurality of aromatic rings are connected by a boron atom, an oxygen atom, or the like, a material for an organic device, an organic electroluminescent element, a display device, and a lighting device. The compound of the present invention can provide a compound having high electron injection characteristics and high electron mobilityThe material for an electron transport layer or the material for an electron injection layer can be used to produce an organic device having a low driving voltage, for example, an organic EL element.

Description

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

Technical Field

The present invention relates to a polycyclic aromatic compound and a multimer thereof (hereinafter, also collectively referred to as "polycyclic aromatic compound"), a material for an organic device, an organic electroluminescent element, an organic field effect transistor, an organic thin-film solar cell, a display device, and a lighting device using the same. In this specification, an "organic electroluminescent element" may be referred to as an "organic EL (electroluminescence) element" or simply as an "element".

Background

Conventionally, various studies have been made on display devices using light emitting elements that emit light by an electric field, in order to achieve power saving and reduction in thickness, and further, active studies have been made on organic electroluminescent elements including organic materials, in order to facilitate weight reduction and size increase. In particular, active studies have been made to develop an organic material having light-emitting characteristics such as blue, which is one of the three primary colors of light, and to develop an organic material having charge transport capability (having a possibility of becoming a semiconductor or a superconductor) of holes, electrons, and the like, regardless of a high molecular compound and a low molecular compound.

The organic EL 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. In the layer containing an organic compound, a light-emitting layer; or a charge transporting/injecting layer or the like that transports or injects charges such as holes, electrons, or the like, and various organic materials suitable for these layers have been developed.

As a material for the light-emitting layer, for example, a benzofluorene compound has been developed (international publication No. 2004/061047). Further, as the hole transporting material, for example, triphenylamine compounds and the like have been developed (Japanese patent laid-open No. 2001-172232). Further, as an electron transport material, for example, an anthracene compound has been developed (Japanese patent laid-open No. 2005-170911).

In recent years, as a material used for an organic EL device or an organic thin film solar cell, a material in which a triphenylamine derivative is improved has been reported (international publication No. 2012/118164). The material is prepared from the following materials: referring to N, N '-diphenyl-N, N' -bis (3-methylphenyl) -1,1 '-biphenyl-4, 4' -diamine (TPD) which has been put into practical use, the aromatic rings constituting triphenylamine are linked to each other, thereby improving the planarity thereof. 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 a material other than the NO-linked compound are unknown because the electron state of the whole compound differs depending on the element to be linked. Examples of such compounds are also disclosed in other documents (International publication No. 2011/107186). For example, a compound having a conjugated structure with a large triplet exciton energy (T1) can emit phosphorescence with a shorter wavelength, and is therefore useful as a material for a blue light-emitting layer. Further, as an electron-transporting material or a hole-transporting material which sandwiches the light-emitting layer, a compound having a novel conjugated structure large in T1 is also required.

[ 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 for organic EL elements, but in order to increase the options for materials for organic EL elements, it is desired to develop a material containing a compound different from the conventional one. In particular, organic EL characteristics obtained from materials other than the NO-linking compound reported in patent documents 1 to 4 and a method for producing the same are not known.

Patent document 6 reports a polycyclic aromatic compound containing boron and an organic EL element using the same, but in order to further improve element characteristics, an electron transport material capable of improving light emission efficiency and element lifetime is required.

[ means for solving problems ]

As a result of diligent research directed toward solving the above problems, the present inventors have found that an excellent organic EL element can be obtained by configuring, for example, an organic EL element by disposing an electron transport layer containing a polycyclic aromatic compound into which a nitrogen-containing group having a specific structure is introduced between a pair of electrodes, and have completed the present invention. Namely, the present invention provides the following polycyclic aromatic compounds.

In the present specification, the chemical structure or the substituent may be represented by carbon number, but the carbon number in the case of substitution with a substituent on the chemical structure, substitution with a substituent on a substituent, or the like means the carbon number of each of the chemical structure or the substituent, and does not mean 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 phrase "substituent B having a carbon number Y substituted with a substituent a having a carbon number X" means that "substituent a having a carbon number X" is substituted with "substituent B having a carbon number Y" in which the carbon number Y is not the total carbon number of substituent a and substituent B. For example, the phrase "substituent B having a carbon number Y substituted with a 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.

Item 1.

Disclosed is a polycyclic aromatic compound represented by the general formula (1) below or a polymer of a polycyclic aromatic compound having a plurality of structures represented by the general formula (1) below.

In the formula (1), ring A, ring B and ring C are each independently an aryl ring or a heteroaryl ring, at least one hydrogen in the rings may be substituted, and ring B and ring C may be linked by-O-,

In the general formula (BiN), ring D is a heteroaryl ring containing at least one N, ring E is an aromatic or non-aromatic ring containing at least one N, an aromatic or non-aromatic condensed ring may be formed between ring D and ring E, and at least one hydrogen in the rings may be substituted,

at least one hydrogen in ring A, ring B and ring C is substituted by a group represented by the formula (BiN) through a linking group, representing a bonding position,

at least one of the A ring, the B ring, the C ring, the aryl group and the heteroaryl group in the compound or structure represented by the formula (1) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, at least one-CH in the cycloalkane₂-may be substituted by-O-, and,

at least one hydrogen in the compound or multimer thereof may be substituted with cyano, halogen, or deuterium.

Item 2.

The polycyclic aromatic compound or the multimer thereof according to item 1, wherein at least one of ring A, ring B, ring C, ring D, ring E and the fused ring may be substituted by a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group, a substituted or unsubstituted diarylboryl group (both aryl groups may be bonded via a single bond or a linking group), a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, or a substituted silyl group,

The A, B and C rings have a 5-or 6-membered ring bonded in common to the condensed bicyclic structure comprising the central element "B (boron)" and two elements "O (oxygen)" in the center of formula (1),

the linking group is a single bond, arylene, heteroarylene, alkylene, alkenylene, alkynylene, -O-, -S-, > N-R, or a combination thereof, R > N-R is aryl, heteroaryl, alkyl, or cycloalkyl, at least one hydrogen in the linking group can be substituted with aryl, heteroaryl, alkyl, or cycloalkyl,

in the case of multimers, dimers or trimers having two or three structures represented by formula (1).

Item 3.

The polycyclic aromatic compound or multimer thereof according to item 1, wherein the polycyclic aromatic compound is represented by the following general formula (2).

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

any of the a ring, the b ring, and the C ring "— (C (-R) ═" (here, R is R in the formula (2))¹～R¹¹) May be substituted with "-N ═ and any of" -C (-R) ═ C (-R) - "(here, R is R in the formula (2) ¹～R¹¹) May be substituted with "-N (-R) -", "-O-", or "-S-", wherein R of "-N (-R) -" is aryl, alkyl, or cycloalkyl,

R¹～R¹¹each independently is hydrogen, aryl, heteroaryl, diarylamino, diheteroarylArylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, or alkylbicycloalkylsilyl groups, at least one of which may be substituted with aryl, heteroaryl, alkyl, or cycloalkyl groups,

R¹～R¹¹may be bonded to each other and together with the a-ring, b-ring or c-ring form an aryl ring or heteroaryl ring, at least one hydrogen in the formed ring may be substituted by an aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), an alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl group, at least one of which may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group,

R⁷And R⁸Can be bonded to form-O-,

in the formula (BiN) in item 1,

a C2-30 heteroaryl ring containing at least one N, an E ring containing at least one N, an aromatic ring containing 2-30 carbon atoms or a non-aromatic ring containing 2-30 carbon atoms, and an aromatic or non-aromatic condensed ring containing 2-15 carbon atoms is formed between the D ring and the E ring,

at least one hydrogen of the D ring, the E ring and the fused ring may be substituted by an aryl group, a heteroaryl group, a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, a diarylboryl group (both aryl groups may be bonded via a single bond or a linking group), an alkyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, a triarylsilyl group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group or an alkylbicycloalkylsilyl group, at least one hydrogen of which may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group,

the R is¹～R¹¹Is a group represented by the formula (BiN) in item 1 through which a linking group is interposed, orAt least one hydrogen of the aryl or heteroaryl ring is substituted by a group represented by formula (BiN) via a linking group, representing a bonding position,

the linking group is a single bond, an arylene group having 6 to 30 carbon atoms, a heteroarylene group having 2 to 30 carbon atoms, an alkylene group having 1 to 24 carbon atoms, an alkenylene group having 1 to 24 carbon atoms, an alkynylene group having 1 to 24 carbon atoms, -O-, -S-, > N-R or a combination thereof, wherein R > N-R is an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 16 carbon atoms, and at least one hydrogen in the linking group is substituted by an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 16 carbon atoms,

At least one hydrogen in the compound or multimer thereof may be substituted with cyano, halogen or deuterium,

at least one of the a-ring, the b-ring, the c-ring, the formed ring, aryl and heteroaryl in the compound or structure represented by the formula (2) may be condensed with at least one cycloalkane having 3 to 24 carbon atoms, wherein at least one hydrogen in the cycloalkane may be substituted with an aryl having 6 to 30 carbon atoms, a heteroaryl having 2 to 30 carbon atoms, an alkyl having 1 to 24 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms, and at least one-CH in the cycloalkane may be substituted with an aryl having 6 to 30 carbon atoms, an alkyl having 2 to 30 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms₂-may be substituted by-O-, and,

in the case of multimers, dimers or trimers having two or three structures represented by formula (2).

Item 4.

The polycyclic aromatic compound or the multimer thereof according to item 3, wherein,

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

any of the a ring, the b ring, and the C ring "— (C (-R) ═" (here, R is R in the formula (2))¹～R¹¹) May be substituted with "-N ═ and any of" -C (-R) ═ C (-R) - "(here, R is R in the formula (2)¹～R¹¹) Can be substituted by "-N (-R) -", "-O-", or "-S-", wherein R of the "-N (-R) -" is aryl with 6-10 carbon atoms, alkyl with 1-5 carbon atoms, or cycloalkyl with 5-10 carbon atoms,

R¹～R¹¹each independently is hydrogen, carbon 6 to 30 carbon atoms of aryl group, 2 to 30 carbon atoms of heteroaryl group, two aryl amino groups (wherein, aryl group is 6 to 12 carbon atoms of aryl group), two aryl boron group (wherein, aryl group is 6 to 12 carbon atoms of aryl group, two aryl groups can be bonded through single bond or linking group), 1 to 24 carbon atoms of alkyl group, 3 to 24 carbon atoms of cycloalkyl group, 1 to 24 carbon atoms of alkoxy group, 6 to 30 carbon atoms of aryloxy group, three aryl silyl group (wherein, aryl group is 6 to 12 carbon atoms of aryl group), three alkyl silyl group (wherein, alkyl is 1 to 6 carbon atoms of alkyl group), at least one hydrogen of them is substituted by 1 to 12 carbon atoms of alkyl group or 3 to 16 carbon atoms of cycloalkyl group,

R¹～R¹¹wherein adjacent groups in (a) may be bonded to each other to form an aryl ring having 9 to 16 carbon atoms or a heteroaryl ring having 6 to 15 carbon atoms together with the a, b or c ring, at least one hydrogen in the ring may be substituted by an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), a diarylboron group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms, and both aryl groups may be bonded via a single bond or a linking group), an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group having 3 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 6 carbon atoms), at least one of them may be substituted by an alkyl group having 1 to 12 carbon atoms or a cycloalkyl,

R⁷And R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

a C2-20 heteroaryl ring containing at least one N, an E ring containing at least one N, an aromatic ring containing 2-20 carbon atoms or a non-aromatic ring containing 2-20 carbon atoms, and an aromatic or non-aromatic condensed ring containing 2-10 carbon atoms is formed between the D ring and the E ring,

at least one hydrogen of the D ring, the E ring and the fused ring may be substituted with an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms, and both aryl groups may be bonded via a single bond or a linking group), an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group having 3 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 12 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 6 carbon atoms), and at least one hydrogen of these may be substituted with an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 16 carbon atoms,

the R is¹～R¹¹Is a group represented by the formula (BiN) through a linker, or at least one hydrogen in the formed aryl or heteroaryl ring is substituted by a group represented by the formula (BiN) through a linker,

The linking group is a single bond, an arylene group having 6 to 12 carbon atoms, a heteroarylene group having 2 to 15 carbon atoms, an alkylene group having 1 to 12 carbon atoms, an alkenylene group having 1 to 12 carbon atoms, an alkynylene group having 1 to 12 carbon atoms, -O-, -S-, > N-R or a combination thereof, wherein R > N-R is an aryl group having 6 to 10 carbon atoms, a heteroaryl group having 2 to 10 carbon atoms, an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 5 to 10 carbon atoms, at least one hydrogen in the linking group is substituted by an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 5 to 10 carbon atoms,

at least one of the a-ring, the b-ring, the c-ring, the formed ring, aryl and heteroaryl in the compound or structure represented by the formula (2) may be condensed with at least one cycloalkane having 3 to 16 carbon atoms, wherein at least one hydrogen in the cycloalkane may be substituted with an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms,

in the case of multimers, dimers having two structures represented by formula (2).

Item 5.

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

any of the a ring, the b ring, and the C ring "— (C (-R) ═" (here, R is R in the formula (2)) ¹～R¹¹) May be substituted with "-N ═ and any of" -C (-R) ═ C (-R) - "(here, R is R in the formula (2)¹～R¹¹) Can be substituted by "-N (-R) -", "-O-", or "-S-", wherein R of the "-N (-R) -" is aryl with 6-10 carbon atoms, alkyl with 1-5 carbon atoms, or cycloalkyl with 5-10 carbon atoms,

R¹～R¹¹independently hydrogen, an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), a diarylboron group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms, and both aryl groups may be bonded by a single bond or a linking group), an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 16 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 4 carbon atoms), at least one hydrogen of which may be substituted by an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 5 to 10 carbon atoms,

R¹～R¹¹wherein adjacent groups in (a) may be bonded to each other to form an aryl ring having 9 to 16 carbon atoms or a heteroaryl ring having 6 to 15 carbon atoms together with the a, b or c ring, at least one hydrogen in the ring may be substituted by an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), a diarylboron group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms, and both aryl groups may be bonded via a single bond or a linking group), an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 16 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 4 carbon atoms), at least one of them may be substituted by an alkyl group having 1 to 4 carbon atoms or a cycloalkyl,

R⁷And R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

a C2-10 heteroaryl ring containing at least one N, an E ring containing at least one N, an aromatic ring containing 2-10 carbon atoms or a non-aromatic ring containing 2-10 carbon atoms, and an aromatic or non-aromatic condensed ring containing 2-10 carbon atoms is formed between the D ring and the E ring,

at least one hydrogen of the D ring, the E ring and the fused ring may be substituted with an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a diarylamino group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms, and both aryl groups may be bonded via a single bond or a linking group), an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 16 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 4 carbon atoms), and at least one hydrogen of these may be substituted with an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 5 to 10 carbon atoms,

The linking group is a single bond, an arylene group having 6 to 10 carbon atoms, an alkylene group having 1 to 6 carbon atoms, an alkenylene group having 1 to 6 carbon atoms, -O-, or a combination thereof, at least one hydrogen in the linking group may be substituted by an alkyl group having 1 to 4 carbon atoms,

Item 6.

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

any of the a ring, the b ring, and the C ring "— (C (-R) ═" (here, R is R in the formula (2))¹～R¹¹) May be substituted with "-N ═ N",any of — (C (-R) ═ C (-R) - "(here, R is R in the formula (2))¹～R¹¹) Can be substituted by "-N (-R) -", "-O-", or "-S-", wherein R of the "-N (-R) -" is aryl with 6-10 carbon atoms, alkyl with 1-5 carbon atoms, or cycloalkyl with 5-10 carbon atoms,

R¹～R¹¹Independently hydrogen, 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 10 carbon atoms), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 4 carbon atoms), at least one hydrogen of which is substituted by an alkyl group having 1 to 4 carbon atoms,

R⁷and R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

ring D is 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, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, or a furazan ring,

ring E is 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, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, or a furazan ring,

The condensed ring is a tetrahydrobenzene ring, a dihydrobenzene ring, a cyclopentane ring or a cyclohexane ring,

at least one hydrogen of the ring D, the ring E and the fused ring may be substituted with 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 10 carbon atoms), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a triarylsilyl group (wherein the aryl group is an aryl group having 6 to 10 carbon atoms), or a trialkylsilyl group (wherein the alkyl group is an alkyl group having 1 to 4 carbon atoms), and at least one hydrogen of these may be substituted with an alkyl group having 1 to 4 carbon atoms,

the linking group is a single bond, phenylene, naphthylene, alkylene group having 1 to 4 carbon atoms, -O-, or a combination thereof, at least one hydrogen in the linking group may be substituted by an alkyl group having 1 to 4 carbon atoms,

Item 7.

The polycyclic aromatic compound or the multimer thereof according to any one of items 1 to 5, wherein the group represented by the formula (BiN) is a group represented by any one of the following formulae.

Me in the structural formula represents methyl and represents bonding position.

Item 8.

The polycyclic aromatic compound or the multimer thereof according to any one of claims 3 to 7, wherein, in the formula (2), R¹And R³，R⁴And R¹¹，R⁵And R¹⁰，R⁶And R⁹，R²、R⁴And R¹¹，R²、R⁵And R¹⁰Or R is²、R⁶And R⁹Is a group represented by the formula (BiN).

Item 9.

The polycyclic aromatic compound according to claim 1, which is represented by any one of the following structural formulae.

Item 10.

A material for organic devices, comprising the polycyclic aromatic compound according to any one of items 1 to 9 or a multimer thereof.

Item 11.

The material for organic devices according to item 10, which is a material for organic electroluminescent elements, a material for organic field effect transistors, or a material for organic thin film solar cells.

Item 12.

The material for an organic device according to item 11, wherein the material for an organic electroluminescent element is a material for an electron transport layer or a material for an electron injection layer.

Item 13.

An organic electroluminescent element comprising: a pair of electrodes including an anode and a cathode; a light-emitting layer disposed between the pair of electrodes; and at least one of an electron transport layer and an electron injection layer disposed between the cathode and the light-emitting layer, wherein the at least one of the electron transport layer and the electron injection layer contains the material for an organic device according to item 12.

Item 14.

The organic electroluminescent element according to claim 13, 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, carbazole derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, and hydroxyquinoline metal complexes.

Item 15.

The organic electroluminescent element according to item 13 or item 14, wherein at least one of the electron transport layer and the electron injection layer contains at least one selected from the group consisting of an alkali metal, an alkaline earth metal, a rare earth metal, an oxide of an alkali metal, an oxide of an alkaline earth metal, an oxide of a rare earth metal, a halide of an alkali metal, a halide of an alkaline earth metal, a halide of a rare earth metal, an organic complex of an alkali metal, an organic complex of an alkaline earth metal, and an organic complex of a rare earth metal.

Item 16.

The organic electroluminescent element according to any one of claims 13 to 15, wherein the light-emitting layer contains at least one selected from the group consisting of a polycyclic aromatic compound represented by the following general formula (6), a polycyclic aromatic compound represented by the following general formula (7), and a polycyclic aromatic compound represented by the following general formula (8).

In the above-mentioned formula (6),

ring A, ring B and ring C are each independently an aryl or heteroaryl ring, at least one hydrogen in the rings may be substituted,

X¹and X²Independently of each other > O, > N-R, > C (-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R)₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, and additionally, said R > N-R and said > C (-R)₂At least one of R of (A) may be bonded to at least one of the A, B and C rings through a linking group,

a ring, B ring, C ring, aryl group and heteroaryl group in the compound represented by the formula (6)Can be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane being substituted, at least one-CH in the cycloalkane ₂-may be substituted by-O-, and,

at least one hydrogen in the compound represented by formula (6) may be substituted with cyano, halogen, or deuterium.

In the above-mentioned formula (7),

X¹、X²and X³Independently of each other > O, > N-R, > C (-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R)₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, and additionally, said R > N-R and said > C (-R)₂At least one of R of (A) may be bonded to at least one of the A, B and C rings through a linking group,

at least one of the A ring, the B ring, the C ring, the aryl group and the heteroaryl group in the compound or structure represented by the formula (7) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, at least one-CH in the cycloalkane₂-may be substituted by-O-, and,

at least one hydrogen in the compound represented by formula (7) may be substituted with cyano, halogen, or deuterium.

In the above-mentioned formula (8),

Ring A and ring B are each independently an aryl or heteroaryl ring, at least one hydrogen in the rings being substituted,

X¹and X²Independently of each other > O, > N-R, > C (-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R)₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, and additionally, said R > N-R and said > C (-R)₂At least one of R of (A) and (B) may be bonded to at least one of the A ring and the B ring through a linking group,

R⁴and R⁷Independently represents hydrogen, 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), an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms,

at least one of the A ring, the B ring, the aryl group and the heteroaryl group in the compound or structure represented by the formula (8) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, at least one-CH in the cycloalkane₂-may be substituted by-O-, and,

at least one hydrogen in the compound represented by formula (8) may be substituted with cyano, halogen, or deuterium.

Item 17.

A display device or a lighting device, comprising the organic electroluminescent element according to any one of items 13 to 16.

[ Effect of the invention ]

According to a preferred embodiment of the present invention, a novel polycyclic aromatic compound which can be used as a material for an organic device such as a material for an organic EL element, for example, can be provided, and by using the polycyclic aromatic compound, an excellent organic device such as an organic EL element can be provided.

Specifically, the present inventors have found that a polycyclic aromatic compound (basic skeleton portion) in which aromatic rings are connected by boron and oxygen, which are hetero elements, has a large Highest Occupied Molecular Orbital (HOMO) -Lowest Unoccupied Molecular Orbital (LUMO) gap (band gap Eg in a thin film) and a high band gap Eg in a thin filmTriplet excitation energy (E)_T). The reason is considered to be that: since the 6-membered ring containing a hetero element has low aromaticity, inhibition of the HOMO-LUMO gap decreases with expansion of the conjugated system, and single-occupied molecular orbital (SOMO) 1 and SOMO2 in the triplet excited state (T1) are localized by electron perturbation of the hetero element. Further, since the hetero element-containing polycyclic aromatic compound (basic skeleton portion) of the present invention has a small exchange interaction between both orbitals due to localization of SOMO1 and SOMO2 in the triplet excited state (T1), the energy difference between the triplet excited state (T1) and the singlet excited state (S1) is small, and TADF (thermally activated delayed fluorescence) is shown, and therefore, it can be effectively used as a fluorescent material for an organic EL device (including a device using TADF). In addition, has high triplet excitation energy (E) _T) The material of (3) can also be effectively used as an electron-transporting layer or a hole-transporting layer of a phosphorescent organic EL element or an organic EL element using TADF. Further, the polycyclic aromatic compound (basic skeleton portion) can arbitrarily change the energy of HOMO and LUMO by introducing a substituent, and therefore, the ionization potential and the electron affinity can be optimized according to the peripheral material.

The nitrogen-containing substituent in the present invention has a chelating structure such as bipyridine or 1, 10-phenanthroline in the substituent, and therefore can reduce the electron injection barrier by chelating with a lithium atom contained in, for example, a Li/Al cathode. As described above, the BO 2-based polycyclic aromatic skeleton as the basic skeleton portion exhibits high electron mobility, and therefore electron injection characteristics can be improved by introducing a nitrogen-containing substituent in the present invention, and a more useful material for an electron transporting layer or a more useful material for an electron injecting layer can be obtained. By using the material for the electron transport layer or the material for the electron injection layer having both high electron injection property and high electron mobility in this manner, an organic device having a low driving voltage, for example, an organic EL element can be manufactured. Further, since the BO 2-based polycyclic aromatic skeleton has a high triplet level due to the multiple resonance effect, the compound of the present invention is also effective as a hole blocking material in a phosphorescent organic EL device or a TADF organic EL device.

Drawings

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

[ description of symbols ]

100: organic electroluminescent element/organic EL 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

Detailed Description

1. Polycyclic aromatic compound and multimer thereof

The present invention is a polycyclic aromatic compound represented by the following general formula (1) or a multimer of a polycyclic aromatic compound having a plurality of structures represented by the following general formula (1), wherein at least one hydrogen in ring a, ring B, and ring C is substituted with a group represented by the following general formula (BiN) via a linking group. Also preferred is a polycyclic aromatic compound represented by the following general formula (2) or a multimer of a polycyclic aromatic compound having a plurality of structures represented by the following general formula (2), wherein R is¹～R¹¹At least one of which is a group represented by the following general formula (BiN) through which a linking group is interposed, or an aryl ring or heteroaryl ring (R) formed¹～R¹¹A ring in which adjacent groups are bonded to each other and formed together with the a-ring, the b-ring, or the c-ring) is substituted with a group represented by formula (BiN) via a linking group. The definitions of the symbols in the following structural formulae are the same as those of the symbols in the general formulae (1), (2) and (BiN), and the same applies to the following.

The a ring, the B ring and the C ring in the general formula (1) are each independently an aryl ring or a heteroaryl ring, and at least one hydrogen in the rings may be substituted by a substituent. The substituent is preferably a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group (an amino group having an aryl group and a heteroaryl group), a substituted or unsubstituted diarylboron group (two aryl groups may be bonded via a single bond or a linking group), a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, or a substituted silane group. Examples of the substituent when the group has a substituent include: aryl, heteroaryl, alkyl or cycloalkyl. In addition, the aryl ring or heteroaryl ring preferably has a 5-or 6-membered ring bonded in common to the condensed bicyclic structure in the center of general formula (1) containing the central element "B (boron)" and two elements "O (oxygen)".

The "condensed bicyclic structure" refers to a structure obtained by condensation of two saturated hydrocarbon rings containing a central element "B (boron)" and two elements "O (oxygen)" shown in the center of the general formula (1). The "6-membered ring bonded in common to the condensed bicyclic structure" means, for example, an a-ring (benzene ring (6-membered ring)) condensed in the condensed bicyclic structure as shown in the general formula (2). The expression "aryl ring or heteroaryl ring having the 6-membered ring" (as the a 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 "aryl ring or heteroaryl ring having 6-membered rings (as A ring)" as used herein means that 6-membered rings constituting all or part of A ring are condensed in the condensed bicyclic structure. The same applies to "ring B (ring B)", "ring C (ring C)", and "5-membered ring".

The A ring (or B ring, C ring) in the general formula (1) corresponds to the a ring and the substituent R thereof in the general formula (2)¹Substituent R³(or b Ring and its substituent R⁸Substituent R¹¹C ring and its substituent R⁴Substituent R⁷). That is, the general formula (2) corresponds to the structure in which "ring A to ring C having 6-membered rings" are selected as ring A to ring C of the general formula (1). Under the meaning, each ring of the general formula (2) is represented by the lower case letters a to c.

In the general formula (2), the substituent R of the ring a, the ring b and the ring c¹Substituent R¹¹May be bonded to each other and together with the a-ring, b-ring or c-ring form an aryl ring or heteroaryl ring, at least one hydrogen in the formed ring may be substituted by an aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), an alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl group, at least one of which may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group. Therefore, the polycyclic aromatic compound represented by the general formula (2) has a structure of a ring constituting the compound changed as shown in the following formulae (2-1) and (2-2) depending on the bonding form among the substituents in the a-ring, b-ring and c-ring. The A ' ring, B ' ring and C ' ring in the formulae correspond to the A ring, B ring and C ring in the general formula (1), respectively.

When the general formula (2) is used for illustration, the A ' ring, the B ' ring and the C ' ring in the formula (2-1) and the formula (2-2) represent a substituent R¹Substituent R¹¹The adjacent groups in (b) are bonded to each other and form an aryl ring or a heteroaryl ring together with the a-ring, the b-ring and the c-ring, respectively (may also be referred to as a fused ring formed by condensing other ring structures in the a-ring, the b-ring or the c-ring). Although not shown in the formula, there are also compounds in which all of the a, B and C rings are changed to a ' ring, B ' ring and C ' ring. Further, according to the above formulae (2-1) and (2-2), for example, R in the b ring⁸R with ring c⁷R of ring b¹¹R with ring a¹R of ring c⁴R with ring a³Etc. do not correspond to "adjacent groups each other" unless otherwise specifiedThey will not bond. That is, "adjacent groups" means groups adjacent to each other on the same ring.

The compound represented by the formula (2-1) or the formula (2-2) is, for example, a compound having an a 'ring (or B' ring or C 'ring) formed by condensing a benzene ring, an indole ring, a pyrrole ring, a benzofuran ring or a benzothiophene ring with respect to a benzene ring as the a ring (or B ring or C ring), and the condensed ring a' (or the condensed ring B 'or the condensed ring C') formed is a naphthalene ring, a carbazole ring, an indole ring, a dibenzofuran ring or a dibenzothiophene ring, respectively.

In addition, the ring B and ring C in the formula (1) may be linked by-O-, and in the formula (2), for example, R⁷And R⁸May be bonded to form-O-.

In the formula (2), any of the a ring, the b ring and the C ring — -C (-R) ═ "(here, R is R in the formula (2)¹～R¹¹) May be substituted with "-N ═ N".

As indicated above, for example, -C (-R) in the C-ring⁵) The "site may be substituted with" -N ═ so that the c ring represented as a benzene ring in formula (2) may be changed to a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, or another nitrogen-containing heteroaryl ring. In addition, as mentioned above, when there is an adjacent group on the c ring (R in the formula)⁶And R⁷) They may be bonded and form a heteroaryl ring (quinoline ring in the formula) together with the c-ring, and the formed ring may be further substituted (represented by n R).

Further, there are also the following modifications.

The same applies to the case where the other site is substituted with "-N", or the case where the a-ring or the b-ring is changed.

In the formula (2), any of the a ring, the b ring and the C ring — "-C (-R) ═ C (-R) -" (this isWhere R is R in the formula (2)¹～R¹¹) May be substituted with "-N (-R) -", "-O-", or "-S-", wherein R of "-N (-R) -" is aryl, alkyl, or cycloalkyl. Further, details regarding the substituents listed herein will be summarized later.

As indicated above, for example, -C (-R) in the C-ring⁷)＝C(-R⁶) The site of the- "may be substituted with" -N (-R) - "," -O- ", or" -S- ", so that the c ring represented as a benzene ring in formula (2) may be changed to an R-substituted pyrrole ring, furan ring, thiophene ring, other nitrogen/oxygen/sulfur-containing heteroaryl ring. In addition, as mentioned above, when there is an adjacent group on the c ring (R in the formula)⁴And R⁵) They may be bonded and form a heteroaryl ring (in the formula, an R-substituted indole ring, a benzofuran ring, or a benzothiophene ring) together with the c ring, and the formed ring may be further substituted (represented by n R).

Further, there are also the following modifications.

The same applies to the case where the other sites are substituted with "-N (-R) -", "-O-", or "-S-" or the case where the a-ring or the b-ring is changed.

In the description of the above formulas (2-1) and (2-2), the a-ring, b-ring, and c-ring are described as benzene rings, but the same applies to the case where the a-ring to c-ring are changed to a nitrogen-containing heteroaryl ring (6-membered ring or 5-membered ring) or an oxygen/sulfur-containing heteroaryl ring (5-membered ring).

Examples of the "aryl ring" of the ring A, ring B and ring C of the general 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. Further, the above The "aryl ring" corresponds to the "R" defined in the general formula (2)¹～R¹¹The "aryl ring" in which adjacent groups in (a) are bonded to each other and form together with the a-ring, the b-ring, or the c-ring "and the a-ring (or the b-ring, the c-ring) already contains a benzene ring having 6 carbon atoms, and therefore the total carbon number 9 of the condensed rings in which 5-membered rings are condensed is the lower limit carbon number.

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 terphenyl ring (m-terphenyl, o-terphenyl, p-terphenyl) as a tricyclic system, an acenaphthene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, an anthracene ring as a condensed tricyclic system, a triphenylene ring, a pyrene ring, a tetracene (naphthacene) ring as a condensed tricyclic system, a perylene ring, a pentacene (pentacene) ring as a condensed pentacene ring, and the like.

Examples of the "heteroaryl ring" of the a ring, B ring and C ring of the general 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 the general formula (2) ¹～R¹¹The heteroaryl ring "in which adjacent groups in (a) are bonded to each other and form a ring a, a ring b, or a ring c" and the ring a (or the ring b or the ring c) already contains a benzene ring having 6 carbon atoms, and therefore the total carbon number of the condensed rings in which 5-membered rings are condensed is the lower limit carbon number.

Specific examples of the "heteroaryl ring" include: 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, phenanthroline ring, phthalazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, acridine ring, phenoxathiin ring, phenoxazine ring, phenothiazine ring, silazine ring, silazane ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, naphthobenzofuran ring, thiophene ring, benzothiophene ring, isoxazole ring, thiazole ring, benzothiophene ring, dibenzothiophene ring, indole ring, 1H-indazole ring, benzimidazole ring, or a, A benzo-phosphacyclopentadiene ring, a dibenzophosphacyclopentadiene ring, a benzo-phosphacyclopentadiene oxide ring, a dibenzophosphacyclopentadiene oxide ring, a furazan ring, a thianthracene ring, an indolocarbazole ring, a benzindolocarbazole ring, a benzindoindolocarbazole ring, an imidazoline ring, an oxazoline ring, or 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 "diarylboryl" (two aryl groups may be bonded via a single bond or a linking group), a substituted or unsubstituted "alkyl", a substituted or unsubstituted "cycloalkyl", a substituted or unsubstituted "alkoxy", a substituted or unsubstituted "aryloxy", or a substituted "silyl", as a first substituent, an aryl group or a "heteroaryl", "diarylamino" or a "diheteroarylamino" heteroaryl group, The aryl and heteroaryl groups of the "arylheteroarylamino group", the aryl group of the "diarylboryl group", and the aryl group of the "aryloxy group" may be exemplified by monovalent groups represented by removing any one hydrogen atom from the "aryl ring" or the "heteroaryl ring".

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), further preferably an alkyl group having 1 to 6 carbon atoms (branched alkyl group having 3 to 6 carbon atoms), particularly preferably an alkyl group having 1 to 5 carbon atoms (branched alkyl group having 3 to 5 carbon atoms), and most 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 (t-amyl), n-hexyl, 1-methylpentyl, 3, 3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, tert-octyl (1,1,3, 3-tetramethylbutyl), 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-tridecyl, 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 a cycloalkyl group having 3 to 24 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, a cycloalkyl group having 5 to 6 carbon atoms, and a cycloalkyl group having 5 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 or 1 to 4 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), still more preferably an alkoxy group having 1 to 6 carbon atoms (an alkoxy group having a branched chain having 3 to 6 carbon atoms), particularly preferably an alkoxy group having 1 to 5 carbon atoms (an alkoxy group having a branched chain having 3 to 5 carbon atoms), and most 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, n-butoxy, isobutoxy, sec-butoxy, tert-pentoxy (t-amyloxy), n-pentoxy, isopentoxy, neopentoxy, tert-pentoxy (t-pentoxy), n-hexoxy, 1-methylpentoxy, 3-dimethylbutoxy, 2-ethylbutoxy, n-heptoxy, 1-methylhexaoxy, n-octoxy, tert-octoxy, 1-methylheptoxy, 2-ethylhexoxy, 2-propylpentoxy, n-nonoxy, 2-dimethylheptoxy, 2, 6-dimethyl-4-heptoxy, 3,5, 5-trimethylhexoxy, n-decoxy, n-undecyloxy, 1-methyldecyloxy, n-dodecyloxy, n-tridecyloxy, 1-hexylheptyloxy group, n-tetradecyloxy group, n-pentadecyloxy group, n-hexadecyloxy group, n-heptadecyloxy group, n-octadecyloxy group, n-eicosyloxy group and the like.

Examples of the "substituted silyl group" as the first substituent include a triarylsilyl group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group, and an alkylbicycloalkylsilyl group as a silyl group substituted with at least one of an aryl group, an alkyl group, and a cycloalkyl group.

As the "trialkylsilyl group", there may be mentioned groups in which three hydrogens of the silyl group are each independently substituted with an aryl group, and the aryl group may refer to the group described as the "aryl group" in the first substituent.

Specific "triarylsilyl group" is, for example, triphenylsilyl group, diphenylmononaphthylsilyl group, monophenyldinaphthylsilyl group, or trinaphthylsilyl group, etc.

As the "trialkylsilyl group", there may be mentioned a group in which three hydrogens of the silyl group are each independently substituted with an alkyl group, and the alkyl group may refer to a group described as the "alkyl group" in the first substituent. Preferred alkyl groups for substitution are alkyl groups having 1 to 4 carbon atoms, and specific examples thereof include: methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, cyclobutyl 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-butylsilyl group, ethyldimethylsilyl group, propyldimethylsilyl group, isopropyldimethylsilyl group, butyldimethylsilyl group, sec-butyldimethylsilyl group, tert-butyldimethylsilyl group, methyldiethylsilyl group, propyldiethylsilyl group, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, tert-butyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, tert-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, tert-butyldiisopropylsilyl, and the like.

As the "tricycloalkylsilyl group", there can be cited a group in which three hydrogens in the silyl group are each independently substituted with a cycloalkyl group, and the cycloalkyl group can refer to a group described as the "cycloalkyl group" in the first substituent. Preferred cycloalkyl groups for substitution are those having 5 to 10 carbon atoms, and specific examples thereof include: cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, 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, decahydronaphthyl, decahydroazulenyl, and the like.

Specific examples of the tricycloalkylsilyl group include tricyclopentylsilyl groups and tricyclohexylsilyl groups.

Specific examples of the dialkylcycloalkylsilyl group substituted with two alkyl groups and one cycloalkyl group and the alkylbicycloalkylsilyl group substituted with one alkyl group and two cycloalkyl groups include silyl groups substituted with a group selected from the specific alkyl groups and cycloalkyl groups.

In addition, "aryl" in "diarylboron group" as the first substituent may refer to the description of the aryl. In addition, the two aryl groups may be linked via a single bond or a linking group (e.g., > C (-R) ₂A > O, > S, or > N-R) bond. Here, > C (-R)₂And R > N-R is aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, or aryloxy (above which is the first substituent), and in the first substituent may be further substituted aryl, heteroaryl, alkyl, or cycloalkyl (above which is the second substituent), and as specific examples of the groups, the descriptions of the aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, alkoxy, or aryloxy as the first substituent may be cited.

In the general formula (2), any of — -C (-R) ═ C (-R) - "(here, R is R in the formula (2))¹～R¹¹) R of the "-N (-R) -" to be substituted is an aryl group, an alkyl group, or a cycloalkyl group, and as the aryl group, the alkyl group, or the cycloalkyl group, the above-mentioned groups can be exemplified. Particularly preferably an aryl group having 6 to 10 carbon atoms (e.g., phenyl group, naphthyl group, etc.), an alkyl group having 1 to 5 carbon atoms or 1 to 4 carbon atoms (e.g., methyl group, ethyl group, etc.), or a cycloalkyl group having 5 to 10 carbon atoms (preferably cyclohexyl group or adamantyl group).

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 "diarylboryl (two aryl groups may be bonded via a single bond or a linking group)", a substituted or unsubstituted "alkyl", a substituted or unsubstituted "cycloalkyl", a substituted or unsubstituted "alkoxy", a substituted or unsubstituted "aryloxy", or a substituted "silyl" as the first substituent indicates that at least one of them may be substituted with a second substituent. Examples of the second substituent include an aryl group, a heteroaryl group, an alkyl group, and a cycloalkyl group, and specific examples thereof can be described with reference to the monovalent group represented by removing any one hydrogen atom from an "aryl ring" or a "heteroaryl ring" and the "alkyl group" or the "cycloalkyl group" as the first substituent. In addition, among the aryl or heteroaryl groups as the second substituent, a structure in which at least one hydrogen of them is substituted with an aryl group such as a phenyl group (specifically, the above-mentioned group), an alkyl group such as a methyl group (specifically, the above-mentioned group), or a cycloalkyl group such as a cyclohexyl group (specifically, the above-mentioned group) is also included in the aryl or heteroaryl groups 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, an alkyl group such as a methyl group, or a cycloalkyl group such as a cyclohexyl group is also included in the heteroaryl group as the second substituent.

R as formula (2)¹～R¹¹The aryl, heteroaryl, diarylamino aryl, diheteroarylamino heteroaryl, arylheteroarylamino aryl and heteroaryl, diarylboron aryl, or aryloxy aryl in (1) may be a monovalent group represented by the general formula (1) in which any one hydrogen atom is removed from an "aryl ring" or a "heteroaryl ring". In addition, as R¹～R¹¹The alkyl group, cycloalkyl group or alkoxy group in (1) can be referred to the description of the "alkyl group", "cycloalkyl group" or "alkoxy group" as the first substituent in the description of the general formula (1). In addition, as R¹～R¹¹As the triarylsilyl group, trialkylsilyl group, tricycloalkylsilyl group, dialkylcycloalkylsilyl group or alkylbicycloalkylsilyl group in (1), the "substituted silyl group" as the first substituent in the description of the general formula "And (4) description. Further, the same applies to aryl, heteroaryl, alkyl or cycloalkyl groups as substituents of the above-mentioned groups. In addition, when R is¹～R¹¹When the adjacent groups in (a) are bonded to each other and form an aryl ring or a heteroaryl ring together with the a-ring, b-ring or c-ring, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl groups as substituents for the rings, and aryl, heteroaryl, alkyl or cycloalkyl groups as further substituents, are also the same.

Specifically, the emission wavelength can be adjusted by steric hindrance, electron donating property, and electron withdrawing property of the structure of the first substituent, and is preferably a group represented by the following structural formula, more preferably a methyl group, a tert-butyl group, a phenyl 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 diphenylamino group, a di-p-tolylamino group, a bis (p-tert-butyl) phenyl group, a carbazolyl group, a 3, 6-dimethylcarbazolyl group, a 3, 6-di-tert-butylcarbazolyl group, and a phenoxy group, and further preferably a methyl group, a tert-butyl group, a phenyl group, an o-tolyl group, a 2, 6-xylyl group, a 2,4, 6-mesityl group, a diphenylamino group, carbazolyl, 3, 6-dimethylcarbazolyl, and 3, 6-di-tert-butylcarbazolyl. From the viewpoint of ease of synthesis, a group having a large steric hindrance is preferable for selective synthesis, and specifically, t-butyl group, o-tolyl group, p-tolyl group, 2, 4-xylyl group, 2, 5-xylyl group, 2, 6-xylyl group, 2,4, 6-mesitylyl group, di-p-tolylamino group, bis (p-t-butyl) phenyl) amino group, 3, 6-dimethylcarbazolyl group, and 3, 6-di-t-butylcarbazolyl group are preferable.

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.

The present invention is a polymer of a polycyclic aromatic compound having a plurality of unit structures represented by general formula (1), preferably a polymer of a polycyclic aromatic compound having a plurality of unit structures represented by general formula (2). The multimer is preferably a dimer to a hexamer, more preferably a dimer to a trimer, and particularly preferably a dimer. The polymer may be in the form of a single compound having a plurality of the unit structures, and for example, may be in the form of a single bond, a linkage group such as alkylene having 1 to 3 carbon atoms, phenylene, naphthylene, or the like bonding a plurality of the unit structures (a linked polymer), or may be in the form of a plurality of unit structures bonded so as to have any of the rings (a ring, B ring, C ring, a ring, B ring, or C ring) contained in the unit structures in common (a ring-shared polymer), or may be in the form of a plurality of unit structures bonded so as to have any of the rings (a ring, B ring, C ring, a ring, B ring, or C ring) contained in the unit structures condensed with each other (a ring, B ring, C ring, a ring, B ring, or C ring) (a ring-condensed polymer), or preferably a ring-shared polymer or a ring-condensed polymer, more preferably a ring-shared polymer.

Examples of such multimers include multimer compounds represented by the following formula (2-4), formula (2-4-1), formula (2-4-2), formula (2-5-1) to formula (2-5-4), or formula (2-6). The multimeric compound represented by the following formula (2-4) is described as a multimeric compound (ring-shared multimer) having a plurality of unit structures represented by the general formula (2) in one compound so as to share a benzene ring as the a ring, in the case of the general formula (2). In addition, the polymer compound represented by the following formula (2-4-1) is described as a polymer compound having two unit structures represented by the general formula (2) in one compound so as to share a benzene ring as an a ring (ring-shared polymer) in the general formula (2). In addition, as for the multimeric compound represented by the following formula (2-4-2), the multimeric compound represented by the following formula (2) is described as a multimeric compound having three unit structures represented by the general formula (2) in one compound so as to share a benzene ring as an a ring (ring-shared multimer). In addition, the polymer compound represented by any one of the following formulae (2-5-1) to (2-5-4) is a polymer compound (ring-shared polymer) having a plurality of unit structures represented by the general formula (2) in one compound so as to share a benzene ring as a b-ring (or c-ring) when the general formula (2) is described. In addition, the polymer compound represented by the following formula (2-6) is described as a polymer compound having a plurality of unit structures represented by the general formula (2) in one compound (ring condensation type polymer) in such a manner that, for example, a benzene ring of a b-ring (or a-ring, c-ring) as a certain unit structure is condensed with a benzene ring of a b-ring (or a-ring, c-ring) as a certain unit structure, in the case of the general formula (2).

The polymer compound may be a polymer formed by combining the multimerization pattern expressed by the formula (2-4), the formula (2-4-1) or the formula (2-4-2) with the multimerization pattern expressed by any one of the formulae (2-5-1) to (2-5-4) or the formula (2-6), may be a polymer formed by combining the multimerization pattern expressed by any one of the formulae (2-5-1) to (2-5-4) with the multimerization pattern expressed by the formula (2-6), or may be a polymer formed by combining the multimerization pattern expressed by the formula (2-4), the formula (2-4-1) or the formula (2-4-2) with the multimerization pattern expressed by any one of the formulae (2-5-1) to (2-5-4) and the multimerization pattern expressed by the formula (2-6) Forming a polymer.

The polycyclic aromatic compound of the present invention has a group represented by the following general formula (BiN) through a linking group.

In the formula (BiN), ring D is a heteroaryl ring containing at least one N, ring E is an aromatic or non-aromatic ring containing at least one N, an aromatic or non-aromatic fused ring may be formed between ring D and ring E, and at least one hydrogen in the rings may be substituted. At the position of × (BiN), the substitution is made to the structure of the general formula (1) or the general formula (2) via a linking group.

The "heteroaryl ring containing at least one N" as the D ring is not particularly limited as long as it is a ring having a "— N ═ C <" group in the ring, and examples thereof include a ring having 2 to 30 carbon atoms, preferably a ring having 2 to 25 carbon atoms, more preferably a ring having 2 to 20 carbon atoms, still more preferably a ring having 2 to 15 carbon atoms, and particularly preferably a ring having 2 to 10 carbon atoms. Examples of the heteroaryl ring include a heterocyclic ring containing carbon and nitrogen as ring-constituting atoms and containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen in addition thereto.

As specific "heteroaryl ring containing at least one N", for example, there can be mentioned: 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, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, or a furazan ring, and the like.

The "aromatic ring or non-aromatic ring containing at least one N" as the E ring is not particularly limited as long as it is a ring having a group "— N ═ C <" in the ring, and examples thereof include a ring having 2 to 30 carbon atoms, preferably a ring having 2 to 25 carbon atoms, more preferably a ring having 2 to 20 carbon atoms, still more preferably a ring having 2 to 15 carbon atoms, and particularly preferably a ring having 2 to 10 carbon atoms. Examples of the aromatic ring or non-aromatic ring include heterocyclic rings containing carbon and nitrogen as ring-constituting atoms and containing 1 to 5 hetero atoms selected from oxygen, sulfur and nitrogen in addition thereto.

Specific examples of the "aromatic ring containing at least one N" include: 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, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, or a furazan ring, and the like.

Examples of the "non-aromatic ring containing at least one N" include a ring in which the aromatic ring loses its aromaticity, for example, a ring in which a substituent is bonded to an unsaturated bond in the aromatic ring to form a saturated bond. As an example, a ring in which the unsaturated bond of the oxazole ring is changed to be saturated as follows is exemplified, and the same description can be made not only for the oxazole ring but also for the other aromatic rings. "Me" in the following structural formula is methyl.

The aromatic or non-aromatic condensed ring formed between the ring D and the ring E includes, for example, a ring having 2 to 15 carbon atoms, preferably a ring having 2 to 10 carbon atoms, and specifically includes a tetrahydrobenzene ring, a dihydrobenzene ring, a cyclopentane ring, a cyclohexane ring, or the like. Specific configurations are exemplified below. The definition of each symbol in the following structural formula is the same as that of each symbol in the general formula (BiN).

At least one hydrogen of the D ring, the E ring, and the fused ring may be substituted with an aryl group, a heteroaryl group, a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, a diarylboryl group (two aryl groups may be bonded via a single bond or a linking group), an alkyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group, or an alkylbicycloalkylsilyl group (the above is the first substituent), and at least one hydrogen of them may be substituted with an aryl group, a heteroaryl group, an alkyl group, or a cycloalkyl group (the above is the second substituent.

As for details of the group, the description of the first substituent and the second substituent in the general formula (1) and the general formula (2) can be cited.

Specific examples of the base represented by formula (BiN) are shown below.

At least one hydrogen in the ring a, ring B and ring C in formula (1) is substituted with a group represented by the following general formula (BiN) via a linking group. R in the formula (2)¹～R¹¹At least one of which is a group represented by the following general formula (BiN) through which a linking group is interposed, or an aryl ring or heteroaryl ring (R) formed¹～R¹¹A ring in which adjacent groups are bonded to each other and formed together with the a-ring, the b-ring, or the c-ring) is substituted with a group represented by formula (BiN) via a linking group.

Linking groups are, for example, single bonds, arylenes, heteroarylenes, alkylenes, alkenylenes, alkynylenes, -O-, -S-, > N-R, or combinations thereof.

Examples of the arylene group and the heteroarylene group include divalent groups represented by the general formulae (1) and (2) in which any two hydrogen atoms are removed from the "aryl ring" and the "heteroaryl ring".

Examples of the alkylene group include divalent groups represented by removing any hydrogen atom from the "alkyl group" as the first substituent in the general formula (1) and the general formula (2). Further, alkenylene and alkynylene are any "-CH" of the alkylene groups mentioned above ₂-CH₂- "a group represented by" — CH ═ CH- "or" — C ≡ C- "respectively.

R > N-R in the linking group is aryl, heteroaryl, alkyl or cycloalkyl, and with regard to the details of said groups, the description of the first substituent and the second substituent in the general formula (1) and the general formula (2) may be cited.

At least one hydrogen in the linking group may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group, and with respect to the details of the groups, the description of the first substituent and the second substituent in the general formula (1) and the general formula (2) may be cited.

Specific examples of the linking group include a single bond, phenylene, naphthylene, alkylene group having 1 to 4 carbon atoms, -O-, a combination thereof, and a group in which at least one hydrogen in the group is substituted by an alkyl group having 1 to 4 carbon atoms, and among the specific examples, a single bond, phenylene, naphthylene, methylene, ethylene, -OCH, and the like are preferable₂CH₂-、-CH₂CH₂O-, or-OCH₂CH₂O-, etc., more preferably a single bond.

The bonding position of the group represented by the formula (BiN) may be any of the positions of the A, B and C rings in the formula (1), specifically, R in the formula (2)¹～R¹¹Or the aryl or heteroaryl ring formed (R)¹～R¹¹The adjacent groups in (1) are bonded to each other and form a ring together with the a-ring, the b-ring or the c-ring), preferably R ¹And R³，R⁴And R¹¹，R⁵And R¹⁰，R⁶And R⁹，R²、R⁴And R¹¹，R²、R⁵And R¹⁰Or R²、R⁶And R⁹The position of (a).

In addition, all or a part of hydrogen in the chemical structure of the polycyclic aromatic compound represented by the general formula (1) or the general formula (2) and the multimer thereof may be substituted with cyano, halogen or deuterium. For example, in formula (1), hydrogen in ring a, ring B, ring C (ring a to ring C are aryl or heteroaryl rings), a substituent for ring a to ring C, and a group represented by formula (BiN) may be substituted with cyano, halogen, or deuterium, and among these, there may be mentioned a form in which all or a part of hydrogen in aryl or heteroaryl is substituted with cyano, halogen, or deuterium. Halogen is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine.

In addition, at least one of the aromatic ring and the heteroaromatic ring in the chemical structure of the polycyclic aromatic compound represented by general formula (1) or general formula (2) and the polymer thereof may be condensed with at least one cycloalkane.

For example, aryl and heteroaryl rings as ring a, ring B, ring C, ring a, ring B, and ring C; aryl (aryl moiety in aryl, diarylamino, arylheteroarylamino, diarylboryl, aryloxy, or triarylsilyl) and heteroaryl (heteroaryl moiety in heteroaryl, diheteroarylamino, or arylheteroarylamino) as a first substituent and a second substituent for ring a to ring C; at least one of an aryl group (same as described above) and a heteroaryl group (same as described above) as the first substituent and the second substituent on the a-ring to the c-ring may be condensed with at least one cycloalkane.

Aryl and heteroaryl rings that are preferably rings A, B, C, a, B, and C; aryl (aryl moiety in aryl, diarylamino, diarylboron, or aryloxy) and heteroaryl (heteroaryl moiety in heteroaryl or diheteroarylamino) as first substituents for the A-ring to the C-ring; at least one of an aryl group (same as described above) and a heteroaryl group (same as described above) as a first substituent on the a-ring to the c-ring may be condensed with at least one cycloalkane.

More preferably aryl rings which are ring A, ring B, ring C, ring a, ring B and ring C; aryl (aryl moiety in aryl or diarylamino) and heteroaryl (heteroaryl moiety in heteroaryl) as first substituents on ring a to ring C; at least one of an aryl group (same as described above) and a heteroaryl group (same as described above) as a first substituent on the a-ring to the c-ring may be condensed with at least one cycloalkane.

More preferably aryl rings which are ring A, ring B, ring C, ring a, ring B and ring C; aryl as a first substituent to ring A to ring C (aryl moiety in aryl or diarylamino); at least one of the aryl groups (the same as above) as the first substituent to the a-ring to the c-ring may be condensed with at least one cycloalkane.

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, bisadamantane, decahydronaphthalene, and decahydroazulene, and alkyl (particularly methyl) substituents, halogen (particularly fluorine) substituents, deuterium substituents having 1 to 5 carbon atoms thereof, and the like.

Among these, for example, a structure in which at least one hydrogen on the carbon at the α -position of a cycloalkane (in a cycloalkane condensed with an aromatic ring or a heteroaromatic ring, the carbon at a position adjacent to the carbon at the condensation site) is substituted, as shown in the following structural formula, is preferable, a structure in which two hydrogens on the carbon at the α -position are substituted is more preferable, and a structure in which a total of four hydrogens on the two carbons at the α -position are substituted is even more 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.

The number of cycloalkanes condensed in one aromatic ring or heteroaromatic ring is preferably 1 to 3, more preferably 1 or 2, and still more preferably 1. For example, examples in which one or more cycloalkanes are condensed in one benzene ring (phenyl group) are shown below. In the respective structural formulae, the term "benzene ring" refers to a benzene ring contained in the skeleton structure of the compound, and the term "phenyl" refers to a bond substituted on the skeleton structure of the compound. Cycloalkanes condensed as shown in the formula (Cy-1-4) and the formula (Cy-2-4) may also be condensed with each other. The same applies to the case where the condensed ring (group) is an aromatic ring or a heteroaromatic ring other than a benzene ring (phenyl group), and the case where the cycloalkane to be condensed is cyclopentane or a cycloalkane other than cyclohexane.

At least one-CH in cycloalkanes₂-may be substituted by-O-. Wherein at a plurality of-CH₂When substituted by-O-, adjacent-CH₂-is not substituted by-O-. For example, one or more-CH groups in cycloalkanes condensed in one benzene ring (phenyl group) are shown below₂Examples of substitution by-O-. In the respective structural formulae, the term "benzene ring" refers to a benzene ring contained in the skeleton structure of the compound, and the term "phenyl" refers to a bond substituted on the skeleton structure of the compound. The same applies to the case where the condensed ring (group) is an aromatic ring or a heteroaromatic ring other than a benzene ring (phenyl group), and the case where the cycloalkane to be condensed is cyclopentane or a cycloalkane other than cyclohexane.

At least one hydrogen in the cycloalkane may be substituted, and as the substituent, for example, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkoxy, aryloxy, a substituted silyl group, deuterium, cyano, or halogen may be cited as a detailed description of the first substituent. Among the substituents, preferred are alkyl groups (e.g., alkyl groups having 1 to 6 carbon atoms), cycloalkyl groups (e.g., cycloalkyl groups having 3 to 14 carbon atoms), halogens (e.g., fluorine), and deuterium. In addition, when the cycloalkyl group is substituted, the cycloalkyl group may be in a substituted form to form a spiro structure, and for example, the following shows an example in which a spiro structure is formed in cycloalkane condensed with one benzene ring (phenyl group). In the respective structural formulae, the term "benzene ring" refers to a benzene ring contained in the skeleton structure of the compound, and the term "phenyl" refers to a bond substituted on the skeleton structure of the compound.

Examples of other forms of cycloalkane condensation include polycyclic aromatic compounds represented by general formula (1) or general formula (2) and polymers thereof substituted with, for example, diarylamino groups condensed with cycloalkane (condensed with the aryl moiety thereof), carbazolyl groups condensed with cycloalkane (condensed with the benzene ring moiety thereof), or benzocarbazolyl groups condensed with cycloalkane (condensed with the benzene ring moiety thereof). As the "diarylamino group", groups described as the "first substituent" can be cited.

More specific examples thereof include polycyclic aromatic compounds represented by the general formula (2) and R in multimers thereof²Are examples of diarylamino groups condensed with cycloalkanes (condensed to the aryl portion thereof) or carbazolyl groups condensed with cycloalkanes (condensed to the phenyl ring portion thereof).

Examples thereof include polycyclic aromatic compounds represented by the following general formula (2-Cy), and polymers of polycyclic aromatic compounds having a plurality of structures represented by the following general formula (2-Cy). In the following structural formula, Cy is a cycloalkane, n is each independently an integer of 1 to 3 (preferably 1), "═ (Cy) n" means that n cycloalkanes are condensed at arbitrary positions of the structure to be condensed (in the following structural formula, n cycloalkanes are condensed in a benzene ring (phenyl group)), and the symbols in the structural formula are defined as in the general formula (2).

Specifically, compounds represented by the following formula are exemplified. In the following formulae, "Cy" represents cycloalkane, n is independently 0 to the maximum condensable number (where n is not all 0), preferably 0 to 2 (where n is not all 0), more preferably 1, and "═ n" means that n cycloalkanes are condensed at an arbitrary position of a structure to be condensed (for example, in the following formula "2-Cy- (1)" n cycloalkanes are condensed at an arbitrary position of each benzene ring). Further, "OPh" in the following structural formula represents a phenoxy group, "Me" represents a methyl group, and each compound may be substituted with the first substituent and a second substituent, at least one of the first substituents being a group represented by the formula (BiN) through a linking group, or at least one hydrogen in the formed aryl ring or heteroaryl ring being substituted with a group represented by the formula (BiN) through a linking group.

More specific examples of the polycyclic aromatic compound of the present invention include compounds represented by the following structural formulae. In addition, the expression of methyl (Me) in the structural formula is omitted.

2. Method for producing polycyclic aromatic compound and multimer thereof

The polycyclic aromatic compound represented by the general formula (1) or the general formula (2) can be produced by a production method described in many conventional documents including international publication No. 2015/102118.

Basically, the intermediate (first reaction) is produced by first bonding the a ring (a ring) to the B ring (B ring) and the C ring (C ring) with a bonding group (a group containing oxygen (O)), and then the final product (second reaction) is produced by bonding the a ring (a ring), the B ring (B ring) and the C ring (C ring) with a bonding group (a group containing a central element B (boron)). In the first Reaction, for example, in the case of etherification, a nucleophilic substitution Reaction, Ullmann Reaction (Ullmann Reaction) or the like 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.

Further, a compound having a desired position being cyanated, halogenated or deuterated can be produced by using a cyanated, halogenated or deuterated raw material at a certain position in the above-mentioned reaction step or by adding a cyanation, halogenation or deuteration step. Similarly, the compound of the present invention can be produced by using a raw material substituted with a group represented by the general formula (BiN) at a certain position in the reaction step, or by adding a step of substituting the group.

As shown in the following schemes (1) and (2), the second reaction is a reaction in which a central element B (boron) bonding the a ring (a ring), the B ring (B ring), and the C ring (C ring) is introduced. First, a hydrogen atom between two elements "O (oxygen)" is ortho-metalated using n-butyllithium, sec-butyllithium, tert-butyllithium, or the like. Subsequently, 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 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. Note that the symbols in the structural formulae in the following schemes (1) to (5) are defined as described above.

Flow (1)

Flow (2)

The above-mentioned schemes (1) and (2) mainly show the methods for producing the polycyclic aromatic compounds represented by the general formulae (1) and (2), but the multimers thereof can be produced by using intermediates having a plurality of rings a, B, and C. The following schemes (3) to (5) will be described in detail. In this case, the target product can be obtained by setting the amount of the reagent such as butyllithium to 2 times or 3 times the amount of the reagent used.

Flow (3)

Flow (4)

Specific examples of the solvent used in the above reaction include tert-butyl benzene, xylene and the like.

In addition, examples of the ortho-metallation reagent 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.

Further, as the metal-exchange reagent of the metal-center element "B (boron)", there can be mentioned: halides of boron such as boron trifluoride, boron trichloride, boron tribromide, and boron triiodide; CIPN (NEt)₂)₂And the like, boron aminated halides; alkoxylates of boron; boron aryloxides, and the like.

Further, as the bransted base, there can be mentioned: 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-dimethylpiperidine₄BNa、Ar₄BK、Ar₃B、Ar₄Si (Ar is an aryl group such as a phenyl group), and the like.

Further, as the lewis acid, 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 each of the above schemes, a bronsted base or a lewis acid may also be used in order to promote the tandem heterolydrol-quart reaction. Among them, when a boron halide such as boron trifluoride, boron trichloride, boron tribromide, or boron triiodide is used, an acid such as hydrogen fluoride, hydrogen chloride, hydrogen bromide, or hydrogen iodide is generated as the aromatic electrophilic substitution reaction proceeds, and therefore it is effective to use a bransted base which captures the acid. On the other hand, when a boron amide halide or a boron alkoxide is used, an amine or an alcohol is generated as the aromatic electrophilic substitution reaction proceeds, and therefore, in many cases, it is not necessary to use a bronsted base, 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.

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

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 EL 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 EL element 100 may have a configuration in which the order of production is reversed, for example, the configuration including: 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.

The form of the layer constituting the organic EL element may be not only the form of the above-mentioned "substrate/anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode", but also the forms of "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 EL 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, glass plates and plates made of transparent synthetic resins such as polyester, polymethacrylate, polycarbonate, and 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 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 particularly, 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. When at least one of the hole injection layer 103 and the hole transport layer 104 is provided between the anode 102 and the light-emitting layer 105, holes are injected into the light-emitting layer 105 through the layer.

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: and polythiophene such as poly (3-methylthiophene), conductive polymer such as polypyrrole and polyaniline. Further, it can be suitably selected from substances used as an anode of an organic EL 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. omega./□ or less functions as an element electrode, but a substrate of about 10. omega./□ is now available, and therefore, for example, a low-resistance product of 100. omega./□ to 5. omega./□, preferably 50. omega./□ to 5. omega./□ 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/transport materials, or are formed by mixing a hole injection/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.

The hole injecting/transporting substance is required to efficiently inject/transport holes from the positive electrode between the electrodes to which an electric field is applied, and it is desirable that the hole injecting efficiency is high and the injected holes are efficiently transported. 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 materials for forming the hole injection layer 103 and the hole transport layer 104, compounds which have been conventionally used as charge transport materials for holes in photoconductive materials; any compound is selected from conventional compounds used for p-type semiconductors and hole injection layers and hole transport layers of organic EL 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,N^4’-bis (9-phenyl-9H-carbazol-3-yl) - [1,1' -biphenyl]4,4' -diamine, N⁴,N⁴,N^4’,N^4’-tetrakis [1,1' -biphenyl]-4-yl) - [1,1' -biphenyl]Triphenylamine derivatives such as 4,4 '-diamine, 4' -tris (3-methylphenyl (phenyl) amino) triphenylamine, starburst amine derivatives, and the like), stilbene derivatives, phthalocyanine derivatives (metal-free phthalocyanine, copper phthalocyanine, and the like), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives or thiophene derivatives, oxadiazole derivatives, and quinoxaline derivatives (for example, 1,4,5,8,9, 12-hexaazatriphenylene-2, 3,6,7,1 0, 11-hexacarbonnitrile, etc.), heterocyclic compounds such as porphyrin derivatives, polysilanes, etc. In the polymer system, a polycarbonate or a styrene derivative, polyvinylcarbazole, polysilane, or the like having the monomer in a 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 doping electron-donating substances, strong electron acceptors such as Tetracyanoquinodimethane (TCNQ) or 2,3,5, 6-tetrafluorotetracyano-1, 4-benzoquinodimethane (F4TCNQ) are known (see, for example, documents m. prasuzu, a. baile, t. friez, k. lyon (m.pfeiffer, a. beyer, t. fritz, k.leo), "application physics promo (appl.phys.lett.), (73), (22), 3202-" 3204(1998), and documents j. buchhawitz, m. prasuzu, t. frietz, k. lyon (j. blochwitz., m. pheiffer, t.fritz, k.leo), "application physics promo (appl.pyscholtz.), (1998). 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 host material having a hole transporting property, for example, benzidine derivatives (TPD, etc.), starburst amine derivatives (TDATA, etc.), or specific metal phthalocyanines (in particular, zinc phthalocyanine (ZnPc), etc.) are known (japanese patent laid-open No. 2005-167175).

< 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.

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, or may be a method in which the host material is mixed in advance and then evaporated at the same time.

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 wt%, more preferably 80 to 99.95 wt%, and still more preferably 90 to 99.9 wt% of the total amount of the light-emitting layer material.

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 wt%, more preferably 0.05 to 20 wt%, and still more preferably 0.1 to 10 wt% of the total material for the light-emitting layer. In the above range, for example, concentration quenching can be prevented, and this is preferable. In addition, from the viewpoint of durability, it is also preferable that a part or all of hydrogen atoms of the dopant material be deuterated.

As the host material, anthracene, pyrene, dibenzo known from the past as a light-emitting body can be mentioned

Fused ring derivatives such as fluorene, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, and cyclopentadiene derivatives. Particularly preferred is an anthracene compound, a fluorene compound or a dibenzo

Is a compound of the formula (I). In addition, from the viewpoint of durability, the main body is also preferableSome or all of the hydrogen atoms of the material are deuterated. Further, it is also preferable that the light-emitting layer is formed by combining a host compound in which a part or all of hydrogen atoms are deuterated and a dopant compound in which a part or all of hydrogen atoms are deuterated.

< Anthracene-based Compound >

The anthracene compound as a host material is, for example, a compound represented by the following general formula (3).

In the formula (3), the reaction mixture is,

x and Ar⁴Each independently is hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted diarylamino, optionally substituted diheteroarylamino, optionally substituted arylheteroarylamino, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted arylthio or optionally substituted silyl, and all of X and Ar⁴Will not be hydrogen at the same time,

at least one hydrogen in the compound represented by formula (3) may be substituted with halogen, cyano, deuterium, or a substituted heteroaryl.

In addition, the structure represented by formula (3) as a unit structure to form polymer (preferably two dimers). In this case, for example, the unit structures represented by the formula (3) may be bonded to each other via X, and X may be a single bond, an arylene group (e.g., phenylene, biphenylene, and naphthylene), a heteroarylene group (e.g., a group having a divalent bonding valence such as a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring, and a phenyl-substituted carbazole ring), or the like.

The details of the aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio or silyl group are described in the following preferred embodiments. Examples of the substituent for these groups include aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, and silyl groups, and details thereof are also described in the following preferred embodiments.

Preferred embodiments of the anthracene compound will be described below. The symbols in the following structures are defined as above.

In the general formula (3), X is a group represented by the formula (3-X1), the formula (3-X2) or the formula (3-X3), and the group represented by the formula (3-X1), the formula (3-X2) or the formula (3-X3) is bonded to the anthracene ring of the formula (3) at the position. It is preferable that both X's are not simultaneously a group represented by the formula (3-X3). More preferably, neither X is a group represented by the formula (3-X2) at the same time.

The naphthylene moiety in the formulae (3-X1) and (3-X2) may be condensed via a benzene ring. The structure obtained by condensation in the above-described manner is as follows.

Ar¹And Ar²Each independently is hydrogen, phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, or,

A phenyl group, a triphenylene group, a pyrenyl group, or a group represented by the formula (a) (including carbazolyl groups, benzocarbazolyl groups, and phenyl-substituted carbazolyl groups). In addition, in Ar¹Or Ar²In the case of the group represented by the formula (A), the group represented by the formula (A) is bonded at one site thereof to the naphthalene ring in the formula (3-X1) or the formula (3-X2).

Ar³Is phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, or the like,

A phenyl group, a triphenylene group, a pyrenyl group, or a group represented by the formula (a) (including carbazolyl groups, benzocarbazolyl groups, and phenyl-substituted carbazolyl groups). In addition, in Ar³In the case of the group represented by formula (a), the group represented by formula (a) is bonded at one site thereof to a single bond represented by a straight line in formula (3-X3). That is, the anthracene ring of the formula (3) is directly bonded to the group represented by the formula (A).

In addition, Ar³May have a substituent, Ar³Wherein at least one hydrogen in the above-mentioned group is further substituted by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, a,

A phenyl group, a triphenylene group, a pyrenyl group, or a group represented by the formula (a) (including a carbazolyl group and a carbazolyl group substituted with a phenyl group). In addition, in Ar³When the substituent is a group represented by the formula (A), the group represented by the formula (A) is bonded to Ar in the formula (3-X3)³Bonding.

Ar⁴Each independently represents hydrogen, phenyl, biphenyl, terphenyl, naphthyl, or a silyl group substituted with an alkyl group having 1 to 4 carbon atoms (methyl, ethyl, tert-butyl, etc.) and/or a cycloalkyl group having 5 to 10 carbon atoms.

Examples of the alkyl group having 1 to 4 carbon atoms which is substituted in the silyl group include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, cyclobutyl and the like, and three hydrogens in the silyl group are independently substituted with the alkyl group.

Specific examples of the "silyl group substituted with an alkyl group having 1 to 4 carbon atoms" include: trimethylsilyl group, triethylsilyl group, tripropylsilyl group, triisopropylsilyl group, tributylsilyl group, tri-sec-butylsilyl group, tri-tert-butylsilyl group, ethyldimethylsilyl group, propyldimethylsilyl group, isopropyldimethylsilyl group, butyldimethylsilyl group, sec-butyldimethylsilyl group, tert-butyldimethylsilyl group, methyldiethylsilyl group, propyldiethylsilyl group, isopropyldiethylsilyl group, butyldiethylsilyl group, sec-butyldiethylsilyl group, tert-butyldiethylsilyl group, methyldipropylsilyl group, ethyldipropylsilyl group, sec-butyldipropylsilyl group, tert-butyldipropylsilyl group, methyldiisopropylsilyl group, ethyldiisopropylsilyl group, butyldiisopropylsilyl group, sec-butyldiisopropylsilyl group, and, T-butyldiisopropylsilane, and the like.

Examples of the cycloalkyl group having 5 to 10 carbon atoms which is substituted in the silane group include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, norbornenyl, 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, decahydronaphthyl and decahydroazulenyl, and three hydrogens in the silane group may be independently substituted by the cycloalkyl group.

Specific examples of the "silyl group substituted with a cycloalkyl group having 5 to 10 carbon atoms" include tricyclopentylsilyl group and tricyclohexylsilyl group.

Examples of the substituted silyl group include a dialkylcycloalkylsilyl group substituted with two alkyl groups and one cycloalkyl group, and an alkylbicycloalkylsilyl group substituted with one alkyl group and two cycloalkyl groups.

In addition, hydrogen in the chemical structure of the anthracene-based compound represented by the general formula (3) may be substituted with a group represented by the formula (a). In the case of substitution by the group represented by formula (a), the group represented by formula (a) is substituted at its site with at least one hydrogen in the compound represented by formula (3).

The group represented by the formula (A) is one of the substituents which the anthracene compound represented by the formula (3) may have.

In the formula (A), Y is-O-, -S-or > N-R²⁹，R²¹～R²⁸Each independently hydrogen, alkyl which may be substituted, cycloalkyl which may be substituted, aryl which may be substituted, heteroaryl which may be substituted, alkoxy which may be substituted, aryloxy which may be substituted, arylthio which may be substituted, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkylbicycloalkylsilyl, amino which may be substituted, halogen, hydroxy or cyano, R²¹～R²⁸Wherein adjacent groups may be bonded to each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring, R²⁹Is hydrogen or a substituted aryl group.

As R²¹～R²⁸The "alkyl group" of the "alkyl group which may be substituted" 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. 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 (t-amyl), n-hexyl, 1-methylpentyl, 3, 3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, tert-octyl (1,1,3, 3-tetramethylbutyl), 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-tridecyl, N-heptadecyl, n-octadecyl, n-eicosyl, and the like.

As R²¹～R²⁸The "cycloalkyl group" of the "optionally substituted cycloalkyl group" in (1) includes a cycloalkyl group having 3 to 24 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, a cycloalkyl group having 5 to 6 carbon atoms, a cycloalkyl group having 5 carbon atoms and the like.

Specific "cycloalkyl" groups include: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and alkyl (particularly methyl) substituents having 1 to 4 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.

As R²¹～R²⁸The "aryl group" of the "aryl group which may be substituted" in (1) includes, for example, an aryl group having 6 to 30 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 "aryl" groups include: phenyl as a monocyclic system; biphenyl as a bicyclic ring system; naphthyl as the condensed bicyclic system; terphenyl (m-terphenyl, o-terphenyl, p-terphenyl) as a tricyclic system; acenaphthenyl, fluorenyl, phenalkenyl, phenanthrenyl as condensed tricyclic systems; triphenylene, pyrenyl, and tetracenyl groups as condensed quaternary ring systems; perylene groups and pentacene groups as condensed five-ring systems, and the like.

As R²¹～R²⁸Examples of the "heteroaryl group" of the "optionally substituted heteroaryl group" in (1) 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, and further preferably a heteroaryl group having 2 to 15 carbon atomsThe heteroaryl group is 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: 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, thienyl, benzo [ b ] thienyl, dibenzothienyl, furazanyl, oxadiazolyl, thianthrenyl, naphthobenzofuryl, naphthobenzothienyl, and the like.

As R²¹～R²⁸Examples of the "alkoxy group" of the "alkoxy group which may be substituted" in (1) 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 "alkoxy" may include: methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy and the like.

R²¹～R²⁸The "aryloxy group" of the "aryloxy group which may be substituted" in (1) is a hydrogen-substituted aryl group of the-OH group, which aryl group may be cited as the R²¹～R²⁸The "aryl" in (1).

R²¹～R²⁸The "arylthio group" of the "arylthio group which may be substituted" in (1) is a hydrogen-substituted aryl group of the-SH group, which may be cited as the R²¹～R²⁸The "aryl" in (1).

As R²¹～R²⁸As the "trialkylsilyl group" in (1), there can be mentioned groups in which three hydrogens of the silyl group are each independently substituted with an alkyl group, and the alkyl group can be cited as the R ²¹～R²⁸The "alkyl" in (1) or (b). Preferred alkyl groups for substitution are alkyl groups having 1 to 4 carbon atoms, and specific examples thereof include: methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, cyclobutyl 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-butylsilyl group, ethyldimethylsilyl group, propyldimethylsilyl group, isopropyldimethylsilyl group, butyldimethylsilyl group, sec-butyldimethylsilyl group, tert-butyldimethylsilyl group, methyldiethylsilyl group, propyldiethylsilyl group, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, tert-butyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, tert-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, tert-butyldiisopropylsilyl, and the like.

As R²¹～R²⁸As the "tricycloalkylsilyl group" in (1), there can be mentioned groups in which three hydrogens in the silyl group are each independently substituted with a cycloalkyl group, which can be cited as said R²¹～R²⁸The "cycloalkyl" in (1) above. Preferred cycloalkyl groups for substitution are those having 5 to 10 carbon atoms, and specific examples thereof include: cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecanBicyclo [1.1.1 ] or bicyclo]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, decahydronaphthyl, decahydroazulenyl, and the like.

Specific examples of the "tricycloalkylsilyl group" include tricyclopentylsilyl group and tricyclohexylsilyl group.

As R²¹～R²⁸The "substituted amino group" of the "amino group which may be substituted" in (1) includes, for example, an amino group in which two hydrogens are substituted with an aryl group or a heteroaryl group. Two hydrogen aryl substituted amino groups are diaryl substituted amino groups, two hydrogen heteroaryl substituted amino groups are diheteroaryl substituted amino groups, and two hydrogen aryl and heteroaryl substituted amino groups are aryl heteroaryl substituted amino groups. Said aryl or heteroaryl may be cited as said R ²¹～R²⁸The "aryl" or "heteroaryl" in (1).

Specific "substituted amino group" includes: diphenylamino, dinaphthylamino, phenylnaphthylamino, bipyrylamino, phenylpyridylamino, naphthylpyridylamino and the like.

As R²¹～R²⁸Examples of the "halogen" in (1) include: fluorine, chlorine, bromine, iodine.

As R²¹～R²⁸In the groups described above, some of the groups may be substituted as described above, and as the substituents in the above case, there may be mentioned: alkyl, cycloalkyl, aryl or heteroaryl. The alkyl, cycloalkyl, aryl or heteroaryl group may be cited as the RR²¹～R²⁸The "alkyl", "cycloalkyl", "aryl" or "heteroaryl" in (1).

"> N-R as Y²⁹R in `²⁹Is hydrogen or a substituted aryl group, as said aryl group, mayCited as said R²¹～R²⁸The group described for the "aryl" in (1) and the substituent thereof may be cited as R²¹～R²⁸The substituent(s) of (1).

R²¹～R²⁸Adjacent groups in (a) may be bonded to each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring. The term "a-1" refers to a group represented by the following formula (A-1) when no ring is formed, and examples of the group represented by any of the following formulae (A-2) to (A-14) include a group represented by the following formula (A-2) and (A-14). Further, at least one hydrogen in the group represented by any one of the formulae (A-1) to (A-14) may be substituted with an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, an arylthio group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group, an alkylbicycloalkylsilyl group, a diaryl-substituted amino group, a diheteroaryl-substituted amino group, an arylheteroaryl-substituted amino group, a halogen group, a hydroxyl group, or a cyano group. Wherein Y and x are as defined above.

As the ring formed by bonding adjacent groups to each other, a hydrocarbon ring may be mentioned, for example, a cyclohexane ring, and as the aryl ring or heteroaryl ring, the above-mentioned R²¹～R²⁸The ring structure illustrated in the "aryl" or "heteroaryl" in (1), the ring being formed by condensation with one or two benzene rings in the formula (A-1).

Examples of the group represented by formula (A) include a group represented by any one of formulae (A-1) to (A-14), preferably a group represented by any one of formulae (A-1) to (A-5) and (A-12) to (A-14), more preferably a group represented by any one of formulae (A-1) to (A-4), even more preferably a group represented by any one of formulae (A-1), (A-3) and (A-4), and particularly preferably a group represented by formula (A-1).

As described above, the group represented by the formula (A) is bonded to the naphthalene ring in the formula (3-X1) or the formula (3-X2),A single bond of the formula (3-X3), Ar of the formula (3-X3)³Bonded and substituted with at least one hydrogen in the compound represented by the formula (3), in the bonding form, preferably with the naphthalene ring in the formula (3-X1) or the formula (3-X2), the single bond in the formula (3-X3), and Ar in the formula (3-X3) ³At least one bonding form.

In addition, regarding the structure of the group represented by the formula (A), the structure is similar to the naphthalene ring in the formula (3-X1) or the formula (3-X2), the single bond in the formula (3-X3), Ar in the formula (3-X3)³The position of the bond and the position of the group represented by the formula (A) which is substituted with at least one hydrogen in the compound represented by the formula (3) in the structure of the group represented by the formula (A) may be any position in the structure of the formula (A), for example, may be at any one of two benzene rings in the structure of the formula (A) or R in the structure of the formula (A)²¹～R²⁸In the formula (A) or "> N-R" as Y in the structure of the formula (A)²⁹"R of²⁹Is bonded at any position in the above.

Examples of the group represented by the formula (a) include the following groups. Wherein Y and x are as defined above.

In addition, all or a part of the hydrogen in the chemical structure of the anthracene compound represented by the general formula (3) may be deuterium.

Specific examples of the anthracene compound include compounds represented by any one of the following formulae (3-1) to (3-142). In the following structural formulae, "Me" represents a methyl group, "D" represents deuterium, and "tBu" represents a tert-butyl group.

As the anthracene compound represented by the formula (3), a compound having a reactive group at a desired position of an anthracene skeleton and X, Ar ⁴And a compound having a reactive group in a partial structure such as the structure of the formula (A) as a starting material, and produced by suzuki coupling, radial and shore coupling, or other conventional coupling reactions. Examples of the reactive group of the reactive compound include halogen and boric acid. As specific production methods, for example, reference is made to: paragraph [0089 ] of International publication No. 2014/141725]～[0175]The synthesis method of (1).

< fluorene-based Compound >

The compound represented by the general formula (4) basically functions as a host material.

In the above-mentioned formula (4),

R¹to R¹⁰Each independently hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the fluorene skeleton in the formula (4) via a linking group), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy, or aryloxy, at least one of which may be substituted with aryl, heteroaryl, alkyl, or cycloalkyl,

in addition, R¹And R²、R²And R³、R³And R⁴、R⁵And R⁶、R⁶And R⁷、R⁷And R⁸Or R⁹And R¹⁰May each be independently bonded to form a fused ring or a spiro ring, and at least one hydrogen in the formed rings may be substituted by an aryl, heteroaryl (which may be bonded to the formed ring via a linking group), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy, or aryloxy group, at least one of which may be substituted by an aryl, heteroaryl, alkyl, or cycloalkyl group, and,

At least one hydrogen in the compound represented by formula (4) may be substituted with halogen, cyano, or deuterium.

The detailed description of each group in the definition of the formula (4) can be cited as in the description of the polycyclic aromatic compound of the formula (1) or the formula (2).

As R¹To R¹⁰The alkenyl group in (3) includes, for example, an alkenyl group having 2 to 30 carbon atoms, preferably an alkenyl group having 2 to 20 carbon atoms, more preferably an alkenyl group having 2 to 10 carbon atoms, further preferably an alkenyl group having 2 to 6 carbon atoms, and particularly preferably an alkenyl group having 2 to 4 carbon atoms. Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

Specific examples of the heteroaryl group include a monovalent group represented by a compound of the following formula (4-Ar1), formula (4-Ar2), formula (4-Ar3), formula (4-Ar4) or formula (4-Ar5) from which any one hydrogen atom is removed.

In the formulae (4-Ar1) to (4-Ar5), Y¹Each independently O, S or N-R, R is phenyl, biphenyl, naphthyl, anthryl or hydrogen,

at least one hydrogen in the structures of formulae (4-Ar1) to (4-Ar5) may be substituted with a phenyl group, a biphenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a methyl group, an ethyl group, a propyl group, or a butyl group.

The heteroaryl group may be bonded to the fluorene skeleton in the formula (4) via a linking group. That is, the fluorene skeleton and the heteroaryl group in the formula (4) may be bonded not only directly but also via a linking group. Examples of the linking group include phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene and-OCH₂CH₂-、-CH₂CH₂O-, or-OCH₂CH₂O-, etc.

R in the formula (4)¹And R²、R²And R³、R³And R⁴、R⁵And R⁶、R⁶And R⁷Or R⁷And R⁸May each independently be bonded to form a fused ring, R⁹And R¹⁰May be bonded to form a spiro ring. From R¹To R⁸The condensed ring formed is a ring condensed with the benzene ring in formula (4), and is an aliphatic ring or an aromatic ring. An aromatic ring is preferable, and as the structure containing a benzene ring in formula (4), a naphthalene ring, a phenanthrene ring, or the like can be mentioned. From R⁹And R¹⁰The spiro ring formed is a ring spiro-bonded to the 5-membered ring in formula (4), and is an aliphatic ring or an aromatic ring. Preferred is an aromatic ring, and fluorene rings and the like can be mentioned.

The compound represented by the general formula (4) is preferably a compound represented by the following formula (4-1), formula (4-2) or formula (4-3), and is R in the general formula (4)¹And R²A compound in which a bonded benzene ring is condensed, R in the general formula (4)³And R⁴A compound in which a bonded benzene ring is condensed, R in the general formula (4) ¹To R⁸Any of which is not bonded.

R in the formula (4-1), the formula (4-2) and the formula (4-3)¹To R¹⁰Is defined as R corresponding to formula (4)¹To R¹⁰R in the same formulae (4-1) and (4-2)¹¹To R¹⁴Is also defined as R in the formula (4)¹To R¹⁰The same is true.

The compound represented by the general formula (4) is more preferably a compound represented by the following formula (4-1A), formula (4-2A) or formula (4-3A), and is R in the formula (4-1), formula (4-2) or formula (4-3), respectively⁹And R¹⁰A compound bonded to form a spiro-fluorene ring.

R in the formula (4-1A), the formula (4-2A) and the formula (4-3A)²To R⁷Are defined as R corresponding to the formulae (4-1), (4-2) and (4-3)²To R⁷R in the same formula (4-1A) and formula (4-2A)¹¹To R¹⁴Is also defined as R in the formula (4-1) and the formula (4-2)¹¹To R¹⁴The same is true.

In addition, all or a part of the hydrogens in the compound represented by formula (4) may be substituted with a halogen, a cyano group or deuterium.

Specific examples of the fluorene-based compound include compounds represented by any one of the following formulae (4-4) to (4-22). In addition, "Me" in the following structural formula represents a methyl group.

< dibenzo >

Series compound >

Dibenzo as host material

The compound is, for example, a compound represented by the following general formula (5).

In the above-mentioned formula (5),

R¹to R¹⁶Each independently is hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the dibenzo of formula (5) via a linking group

Backbone bond), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy, or aryloxy, at least one of which may be substituted with aryl, heteroaryl, alkyl, or cycloalkyl,

in addition, R¹To R¹⁶May be bonded to each other to form a condensed ring, and at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group (which may be bonded to the formed ring via a linking group), a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group, or an aryloxy group, at least one of which may be substituted by an aryl group, a heteroaryl group, an alkyl group, or a cycloalkyl group, and,

at least one hydrogen in the compound represented by formula (5) may be substituted with halogen, cyano, or deuterium.

The detailed description of each group in the definition of the formula (5) can be cited as in the polycyclic aromatic compound of the formula (1) or the formula (2).

Examples of the alkenyl group in the definition of the formula (5) include alkenyl groups having 2 to 30 carbon atoms, preferably alkenyl groups having 2 to 20 carbon atoms, more preferably alkenyl groups having 2 to 10 carbon atoms, further preferably alkenyl groups having 2 to 6 carbon atoms, and particularly preferably alkenyl groups having 2 to 4 carbon atoms. Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

Specific examples of the heteroaryl group include a monovalent group represented by a compound of the following formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5) from which any one hydrogen atom is removed.

In the formulae (5-Ar1) to (5-Ar5), Y¹Each independently O, S or N-R, R is phenyl, biphenyl, naphthyl, anthryl or hydrogen,

at least one hydrogen in the structures of formulae (5-Ar1) to (5-Ar5) may be substituted with a phenyl group, a biphenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a methyl group, an ethyl group, a propyl group, or a butyl group.

The heteroaryl group may be bonded to the dibenzo of formula (5) via a linking group

The skeleton is bonded. Namely, dibenzo in the formula (5)

The backbone and the heteroaryl group may be bonded not only directly but also via a linking group therebetween. Examples of the linking group include phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene and-OCH₂CH₂-、-CH₂CH₂O-, or-OCH₂CH₂O-, etc.

The compound represented by the general formula (5) is preferably R¹、R⁴、R⁵、R⁸、R⁹、R¹²、R¹³And R¹⁶Is hydrogen. In that case, R in the formula (5)²、R³、R⁶、R⁷、R¹⁰、R¹¹、R¹⁴And R¹⁵Each independently is preferably hydrogen, phenyl, biphenyl, naphthyl, anthryl, phenanthryl, a monovalent radical having the structure of the formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5) (the monovalent radical having the structure may be substituted with phenylene, biphenylene, naphthylene, anthrylene, methylene, ethylene, -OCH ₂CH₂-、-CH₂CH₂O-, or-OCH₂CH₂O-and dibenzo in said formula (5)

Backbone bond), methyl, ethyl, propyl, or butyl.

The compound represented by the general formula (5) is more preferably R¹、R²、R⁴、R⁵、R⁷、R⁸、R⁹、R¹⁰、R¹²、R¹³、R¹⁵And R¹⁶Is hydrogen. In that case, R in the formula (5)³、R⁶、R¹¹And R¹⁴At least one (preferably one or both, more preferably one) of (A) and (B) is a single bond, phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH₂CH₂-、-CH₂CH₂O-, or-OCH₂CH₂A monovalent group of O-having a structure of the formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5),

other than the at least one (i.e., other than the position substituted with the monovalent group having the structure) is hydrogen, phenyl, biphenyl, naphthyl, anthryl, methyl, ethyl, propyl, or butyl, and at least one of them may be substituted with phenyl, biphenyl, naphthyl, anthryl, methyl, ethyl, propyl, or butyl.

R in the formula (5)²、R³、R⁶、R⁷、R¹⁰、R¹¹、R¹⁴And R¹⁵The structures represented by the formulae (5-Ar1) to (5-Ar5) are selectedIn the case of a monovalent radical of (3), at least one hydrogen in the structure may react with R in the formula (5)¹To R¹⁶Any of which is bonded to form a single bond.

As dibenzenes

Specific examples of the compound include compounds represented by any one of the following formulas (5-1) to (5-39). Further, "tBu" in the following structural formula represents a tert-butyl group.

< polycyclic aromatic Compound >

The polycyclic aromatic compound as the host material is, for example, a polycyclic aromatic compound represented by the following general formula (6), a polycyclic aromatic compound represented by the following general formula (7), or a polycyclic aromatic compound represented by the following general formula (8). Preferred forms of each compound are a polycyclic aromatic compound represented by the following general formula (6'), a polycyclic aromatic compound represented by the following general formula (7'), and a polycyclic aromatic compound represented by the following general formula (8 '). The definitions of the symbols in the following structural formulae are the same as those of the symbols in the general formulae (6), (7) and (8) and the general formulae (6), (7') and (8'), and the same applies hereinafter. The structural forms of the compounds in the respective formulae and the details of the substituents can be referred to the descriptions in the above general formulae (1) and (2).

In the above-mentioned formulae (6), (7) and (8),

X¹、X²and X³Independently of each other > O, > N-R, > C (-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R) ₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, and additionally, said R > N-R and said > C (-R)₂At least one of R of (A) may be bonded to at least one of the A, B and C rings through a linking group,

at least one of the A ring, the B ring, the C ring, the aryl group and the heteroaryl group in the compound represented by formula (6), formula (7) or formula (8) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, at least one-CH in the cycloalkane₂-may be substituted by-O-, and,

at least one hydrogen in the compound represented by formula (6), formula (7) or formula (8) may be substituted with cyano, halogen or deuterium.

The structural forms of the compounds in the respective formulae and the details of the substituents can be referred to the descriptions in the above general formulae (1) and (2).

In the formulae (6'), (7') and (8'),

any of the rings a, b and C "— (C (-R) ═" (here, R is R in the formula¹～R¹¹) May be substituted with "-N ═ and optionally" -C (-R) ═ C (-R) - "(where R is R in the formulae ¹～R¹¹) May be substituted with "-N (-R) -", "-O-", or "-S-", wherein R of the "-N (-R) -" is aryl, alkyl, or cycloalkyl, and further, in formula (8'), any "-C (-R) ═ in the C ring" (where R is R in formula (8'), "⁴Or R⁷) May be substituted by "-N ═"，

R¹～R¹¹Each independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, or alkylbicycloalkylsilyl, at least one of which may be substituted with aryl, heteroaryl, alkyl, or cycloalkyl,

in addition, R¹～R¹¹May be bonded to each other and together with the a-ring, b-ring or c-ring form an aryl ring or heteroaryl ring, at least one hydrogen in the formed ring may be substituted by an aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), an alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl group, at least one of which may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group,

Wherein R in the formula (8')⁴And R⁷Independently represents hydrogen, 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), an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms,

X¹、X²and X³Independently of each other > O, > N-R, > C (-R)₂And > S or > Se, wherein R > N-R is aryl with 6-12 carbon atoms, heteroaryl with 2-15 carbon atoms, alkyl with 1-6 carbon atoms or cycloalkyl with 3-14 carbon atoms, and > C (-R)₂R in (1) is hydrogen, aryl having 6 to 12 carbon atoms, alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 14 carbon atoms, R > N-R and R > C (-R)₂At least one of R of (a) may be represented by a single bond, -O-, -S-, or-C (-R)₂-is bonded to at least one of said a-, b-and C-rings, said > C (-R)₂R is C1-C6 alkyl or C3-C14 cycloalkyl,

at least one of the a-ring, the b-ring, the c-ring, the formed ring, aryl and heteroaryl in the compound represented by the formula (6'), the formula (7') or the formula (8') may be condensed with at least one cycloalkane having 3 to 24 carbon atoms, wherein at least one hydrogen in the cycloalkane may be substituted with an aryl having 6 to 30 carbon atoms, a heteroaryl having 2 to 30 carbon atoms, an alkyl having 1 to 24 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms, and at least one-CH in the cycloalkane may be substituted with an aryl having 6 to 30 carbon atoms, an alkyl having 1 to 24 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms ₂-may be substituted by-O-, and,

at least one hydrogen in the compound represented by formula (6'), formula (7') or formula (8') may be substituted with cyano, halogen or deuterium.

In the compound of formula (6) or formula (6'), the compound is reacted with X¹And X²Equivalent of X³The compound in which the B ring and the C ring (B ring and C ring) are linked is a compound of formula (7) or formula (7'), and the dimer formed so as to share the C ring (C ring) in the compound of formula (6) or formula (6') is a compound of formula (8) or formula (8 '). Thus, the structures of the respective compounds are similar, and therefore, the compounds of formula (6) or formula (6') will be representatively described below, but the description thereof also applies to the compounds of formula (7) or formula (7') and the compounds of formula (8) or formula (8 ').

The a ring, the B ring and the C ring in the general formula (6) are each independently an aryl ring or a heteroaryl ring, and at least one hydrogen in the rings may be substituted by a substituent. The substituent is a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group (an amino group having an aryl group and a heteroaryl group), a substituted or unsubstituted diarylboron group (two aryl groups may be bonded via a single bond or a linking group), a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, or a substituted silane group. As the substituent when said group has a substituent, there may be mentioned Carrying out: aryl, heteroaryl, alkyl or cycloalkyl. In addition, the aryl ring or heteroaryl ring preferably has a structure including the central elements "B (boron)", "X¹"and" X²"the condensed bicyclic structure in the center of the general formula (6)" has a bonded 5-or 6-membered ring in common.

The A ring (or B ring, C ring) in the formula (6) corresponds to the a ring in the formula (6') and the substituent R thereof¹Substituent R³(or b Ring and its substituent R⁸Substituent R¹¹C ring and its substituent R⁴Substituent R⁷). That is, the general formula (6') corresponds to the structure in which "ring A to ring C having 6-membered rings" are selected as ring A to ring C of the general formula (6). Under the meaning, the rings of the general formula (6') are represented by the lower case letters a to c.

In the general formula (6'), the substituents R of the ring a, ring b and ring c¹Substituent R¹¹May be bonded to each other and together with the a-ring, b-ring or c-ring form an aryl ring or heteroaryl ring, at least one hydrogen in the formed ring may be substituted by an aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl (two aryl groups may be bonded via a single bond or a linking group), an alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl group, at least one of which may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group. Therefore, the polycyclic aromatic compound represented by the general formula (6') has a structure of a ring which constitutes the compound changed depending on the bonding form among the substituents in the a ring, the b ring and the c ring. This case is described as the case of the general formula (1) using the formulas (2-1) and (2-2).

As the "aryl ring" and "heteroaryl ring" as the A ring, B ring and C ring of the general formula (6), the description of the general formula (1) can be cited. In addition, the description of the general formula (1) and the general formula (2) can also be cited for the first substituent and the second substituent to be substituted in the "aryl ring" and the "heteroaryl ring".

X in the general formula (6)¹And X²Are each independently >O、＞N-R、＞C(-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R)₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, R of said > N-R and said > C (-R)₂At least one of R in (A) and (B) may be bonded to at least one of the A ring, the B ring and the C ring through a linking group, and the linking group is preferably-O-, -S-or-C (-R)₂-. Furthermore, the "-C (-R)₂R of the-is hydrogen, alkyl or cycloalkyl. Said description being for X in formula (6')¹And X²The same applies to the other.

Here, "said R > N-R and said > C (-R) in the general formula (6)₂The provision that at least one of R of (A) is bonded to at least one of the A ring, B ring and C ring via a linking group corresponds to "R of > N-R and > C (-R) ₂At least one of R of (a) is represented by a single bond, -O-, -S-, or-C (-R)₂-provision of bonding to at least one of the a-, b-and c-rings.

The specification may be represented by the following compounds: the compound is represented by the following formula (6' -3-1), and has X¹Or X²A ring structure introduced into the condensed rings B 'and C'. That is, for example, a compound having a B ' ring (or C ' ring) in which X is introduced into the benzene ring as the B ring (or C ring) in the general formula (6')¹(or X)²) By condensation of other rings. The condensed ring B '(or the condensed ring C') formed is, for example, a phenoxazine ring, a phenothiazine ring or an acridine ring.

In addition, the specification can also be expressed by the following compounds: the compound is represented by the following formula (6'-3-2) or formula (6' -3-3), and has X¹And X²At least one of which is introduced into the ring structure in the fused ring a'. That is, for example, a compound having an A 'ring in which X is introduced into the benzene ring as the a ring in the formula (6')¹(or X)²Or X¹And X²) By condensation of other rings. The condensed ring A' formed is, for example, a phenoxazine ring, a phenothiazine ringAn oxazine ring or an acridine ring.

X of the formula (6)¹And X²R > N-R in (A) is aryl, heteroaryl, alkyl or cycloalkyl which may be substituted by said second substituent, at least one hydrogen of said aryl, heteroaryl, alkyl or cycloalkyl being for example substituted by alkyl or cycloalkyl. With respect to the aryl, heteroaryl, alkyl or cycloalkyl group, the descriptions of the general formula (1) and the general formula (2) can also be cited. Particularly preferred is an aryl group having 6 to 10 carbon atoms (e.g., phenyl group, naphthyl group, etc.), a heteroaryl group having 2 to 15 carbon atoms (e.g., carbazolyl group, etc.), an alkyl group having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, etc.), or a cycloalkyl group having 5 to 10 carbon atoms (preferably cyclohexyl group or adamantyl group). Said description being for X in formula (6') ¹And X²The same applies to the other.

X of the formula (6)¹And X²Middle > C (-R)₂R of (a) is hydrogen, aryl which may be substituted with said second substituent, alkyl or cycloalkyl, at least one hydrogen in the aryl group being for example substituted with an alkyl group. With respect to the aryl, alkyl or cycloalkyl group, the descriptions of the general formula (1) and the general formula (2) can also be cited. Particularly preferred is an aryl group having 6 to 10 carbon atoms (e.g., phenyl group, naphthyl group, etc.), an alkyl group having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, etc.), or a cycloalkyl group having 5 to 10 carbon atoms (preferably cyclohexyl group or adamantyl group). Said description being for X in formula (6')¹And X²The same applies to the other.

-C (-R) as a linking group in the general formula (6')₂R of the- (O-X-O) -is hydrogen, an alkyl group or a cycloalkyl group, and the description of the general formula (1) and the general formula (2) may be cited for the alkyl group or the cycloalkyl group. Particularly preferably an alkyl group having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, etc.) or a cycloalkyl group having 5 to 10 carbon atoms (preferably cyclohexyl group or adamantyl group).

In addition, all or a part of hydrogen in the chemical structure of the polycyclic aromatic compound represented by the general formula (6) or the general formula (6') may be substituted with cyano, halogen, or deuterium. For example, in the formula (6), ring A, ring B and ring C (ring A to ring C are each aryl)A cyclic or heteroaryl ring), a substituent for the A-ring to the C-ring, and X ¹And X²Is > N-R or > C (-R)₂In the case of R (═ aryl, heteroaryl, alkyl, cycloalkyl), hydrogen may be substituted with cyano, halogen or deuterium, and examples thereof include forms in which all or a part of hydrogen in aryl or heteroaryl is substituted with cyano, halogen or deuterium. Halogen is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine.

In the compound represented by the formula (6) or (6'), the description of the general formula (1) and the general formula (2) can be cited as a form in which at least one of the ring a, ring B, ring C, ring formed, "aryl group and heteroaryl group is condensed with at least one cycloalkane.

Any of the a, b and C rings — -C (-R) ═ in the compound represented by formula (6') (where R is R in the formula)¹～R¹¹) Any form substituted with "-N ═ and any form" — (here, R is R in the formula ═ C (-R) - "¹～R¹¹) Examples of the form substituted with "-N (-R) -", "-O-" or "-S-" include those described in the general formula (2).

The compounds represented by any of general formula (6), general formula (7), and general formula (8), and general formula (6'), general formula (7'), and general formula (8') can be produced in the same manner as the compounds represented by general formula (1) and general formula (2).

< 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/injecting materials, or are formed by mixing an electron transporting/injecting material and a polymer binder.

The electron injection/transport layer is a layer that manages the injection of electrons from the cathode and the transport of electrons, and it is desirable that the injected electrons be efficiently transported with high electron injection efficiency. 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 well as the material having the high electron transport ability. Therefore, the electron injection/transport layer in this embodiment may also function as a layer capable of efficiently blocking 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 arbitrarily from compounds conventionally used as electron transport compounds in photoconductive materials, and conventional compounds used for electron injection layers and electron transport layers of organic EL devices. In the present invention, as the electron transporting material, a polycyclic aromatic compound represented by general formula (1) or general formula (2) can be used.

As the material for the electron transport layer or the electron injection layer, at least one selected from the following materials is preferably contained: 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, phosphorus oxide derivatives, carbazole derivatives, indole derivatives, and the like. 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. The materials can be used alone or in admixture with different materials.

Specific examples of the other electron transport compound include: pyridine derivatives, naphthalene 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-based metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzoxazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, perinone derivatives, coumarin derivatives, substituted derivatives, and the like, Benzoquinoline derivatives (2,2' -bis (benzo [ h ] quinolin-2-yl) -9,9' -spirobifluorene, etc.), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (tris (N-phenylbenzimidazol-2-yl) benzene, etc.), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives of terpyridine, etc., bipyridine derivatives, terpyridine derivatives (1, 3-bis (4' - (2,2 ': 6'2 "-terpyridine)) benzene, etc.), naphthyridine derivatives (bis (1-naphthyl) -4- (1, 8-naphthyridin-2-yl) phenylphosphine oxide, etc.), aldazine derivatives, carbazole derivatives, indole derivatives, phosphorus oxide derivatives, etc, Bisstyryl 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, carbazole derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, and hydroxyquinoline-based metal complexes.

Borane derivatives

The borane derivative is, for example, a compound represented by the following general 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, cycloalkyl, aryl which may be substituted, silyl which may be substituted, a nitrogen-containing heterocycle which may be substituted, or cyano, R¹³～R¹⁶Each independently is an alkyl group which may be substituted, a cycloalkyl group which may be substituted, or an aryl group which may be substituted, X is an arylene group which may be substituted, Y is 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. In addition, as the substituent in the case of "may be substituted" or "substituted", there may be mentioned: aryl, heteroaryl, alkyl or cycloalkyl, and the like.

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

In the formula (ETM-1-1), R¹¹And R¹²Each independently is at least one of hydrogen, alkyl, cycloalkyl, aryl which may be substituted, silyl which may be substituted, a nitrogen-containing heterocycle which may be substituted, or cyano, R¹³～R¹⁶Each independently is an alkyl group which may be substituted, a cycloalkyl group which may be substituted, or an aryl group which may be substituted, R²¹And R²²Each independently is hydrogen, alkyl, cycloalkyl, optionally substituted aryl, optionally substituted silylAt least one of substituted nitrogen-containing heterocyclic ring or cyano group, 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 addition, as the substituent in the case of "may be substituted" or "substituted", there may be mentioned: aryl, heteroaryl, alkyl or cycloalkyl, and the like.

In the formula (ETM-1-2), R¹¹And R¹²Each independently is at least one of hydrogen, alkyl, cycloalkyl, aryl which may be substituted, silyl which may be substituted, a nitrogen-containing heterocycle which may be substituted, or cyano, R ¹³～R¹⁶Each independently is an alkyl group which may be substituted, a cycloalkyl 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. In addition, as the substituent in the case of "may be substituted" or "substituted", there may be mentioned: aryl, heteroaryl, alkyl or cycloalkyl, and the like.

As X¹Specific examples of (2) include divalent groups represented by any one of the following formulae (X-1) to (X-9). Each structural formula represents a bonding site.

(in the formulae, R^aEach independently is alkyl, cycloalkyl or optionally substituted phenyl. )

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), preferably a compound represented by the formula (ETM-2-1) or the formula (ETM-2-2).

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), R ¹¹～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), R¹¹And 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), and the pyridine substituent may be independently substituted with an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 5 to 10 carbon atoms. In addition, the pyridine substituent may be bonded to the anthracene ring or the fluorene ring in each formula via a phenylene group or a naphthylene group. Each structural formula represents a bonding site.

The pyridine substituent is any one of the above formulae (Py-1) to (Py-15), and in the formulae, any one of the following formulae (Py-21) to (Py-44) is preferable. Each structural formula represents a bonding site.

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).

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 R¹²Can be bonded to form a ring, and as a result, cyclobutane, cyclopentane, cyclopentene and ring can be spiro-bonded to the 5-membered ring of the fluorene skeleton Pentadiene, cyclohexane, fluorene or indene, etc.

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 >

Fluoranthene derivatives are, for example, compounds represented by the following general formula (ETM-3), and are 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. Here, as the substituent in the case of substitution, there may be mentioned: aryl, heteroaryl, alkyl or cycloalkyl, and the like.

Specific examples of the fluoranthene derivative include the following compounds.

< BO series 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, cycloalkyl, alkoxy, or aryloxy, at least one of which may be substituted with aryl, heteroaryl, alkyl, or cycloalkyl.

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

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

As for the explanation of the form of the substituent or ring in the formula (ETM-4), the explanation of the polycyclic aromatic compound represented by the above general formula (1) or formula (2) can be cited.

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-5-1).

Ar is each independently divalent benzene or naphthalene, R¹～R⁴Each independently hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms or aryl having 6 to 20 carbon atoms.

Ar may be appropriately selected from divalent benzene or naphthalene, and each of Ar may be different or the same, and is preferably the same from the viewpoint of ease of synthesis of the anthracene derivative. Ar is bonded to pyridine to form "a site including Ar and pyridine", and the site is bonded to anthracene as a group represented by any one of the following formulae (Py-1) to (Py-12), for example. Each structural formula represents a bonding site.

Among the above groups, preferred are groups represented by any one of the formulae (Py-1) to (Py-9), and more preferred are groups represented by any one of the formulae (Py-1) to (Py-6). The two "sites containing Ar and pyridine" bonded to anthracene may be the same or different in structure, and the same structure is preferable from the viewpoint of ease of synthesis of the anthracene derivative. Among them, from the viewpoint of device characteristics, it is preferable that the two "sites containing Ar and pyridine" have the same or different structures.

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 (t-amyl), n-hexyl, 1-methylpentyl, 3-dimethylbutyl, and 2-ethylbutyl, etc., preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl, 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 is preferablyThe aryl group has 6 to 16 carbon atoms, more preferably 6 to 12 carbon atoms, and particularly preferably 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-, 9-) -as condensed tricyclic aryl, 2-) group, pyrene- (1-, 2-, 4-) group, tetracene- (1-, 2-, 5-) group, perylene- (1-, 2-, 3-) group as condensed pentacyclic aryl group, and the like.

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.

One of the anthracene derivatives is, for example, a compound represented by the following formula (ETM-5-2).

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

Ar²Aryl groups each independently having 6 to 20 carbon atoms are the same as the "aryl group having 6 to 20 carbon atoms" in the formula (ETM-5-1)And (5) clearing. 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.

R¹～R⁴Each independently 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, as described in the above formula (ETM-5-1).

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),the polymer may be a linear chain or a branched chain, and examples thereof include a linear 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 (t-amyl), n-hexyl, 1-methylpentyl, 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.

R⁵Is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 16 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, cycloalkyl group having 3 to 16 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.

Here, as the substituent in the case of substitution, there may be mentioned: aryl, heteroaryl, alkyl or cycloalkyl, and the like.

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

R¹～R³Can be the same or different and is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aralkyl, alkenyl, cycloalkene The substituent group includes a group, an alkynyl group, an alkoxy group, an alkylthio group, a cycloalkylthio group, an aryl ether group, an arylthioether group, an aryl group, a heterocyclic group, a halogen group, a cyano group, an aldehyde group, a carbonyl group, a carboxyl group, an amino group, a nitro group, a silane group, and a fused ring formed between adjacent substituents.

Ar¹May be the same or different and is an arylene or heteroarylene group. Ar (Ar)²May be the same or 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, no R is present¹。

The alkyl group in the substituent 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 in the case of substitution 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 such as a benzyl group or a phenylethyl group through which an aliphatic hydrocarbon is interposed, 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 such as a methoxy group through an ether bond, 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 means a group in which an oxygen atom of an ether bond of an alkoxy group is substituted with a sulfur atom.

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

The aryl ether group means an aromatic hydrocarbon group such as a phenoxy group through 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 means 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 aldehyde group, carbonyl group, and amino group may include a group substituted with an aliphatic hydrocarbon, an alicyclic hydrocarbon, an aromatic hydrocarbon, a heterocyclic ring, 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 is, for example, Ar¹And R²、Ar¹And R³、Ar²And R²、Ar²And R³、R²And R³、Ar¹And Ar²Etc. are conjugated or non-conjugated fused rings formed therebetween. 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 derivative ]

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 monocyclic aryl group, (2-, 3-, 4-) biphenyl as bicyclic aryl group, (1-, 2-) naphthyl as 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-4-yl), acenaphthylene- (1-, 3-, 4-, 5-) as condensed tricyclic aryl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalene- (1-, 2-) yl, (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-) 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, naphthyridine ring, 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.

< carbazole derivative >

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

Ar is independently aryl which may be substituted or heteroaryl which may be substituted. n is an integer of 0 to 4, preferably an integer of 0 to 3, and more preferably 0 or 1.

The carbazole 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 not only by a single bond but also by an aryl ring (preferably, a polyvalent benzene ring, naphthalene ring, anthracene ring, fluorene ring, benzofluorene ring, phenalene ring, phenanthrene ring, or triphenylene ring).

Specific examples of the carbazole derivative include the following compounds.

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

< triazine derivative >

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). The details are described in U.S. patent application publication 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 derivative >

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 a 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. In the following structural formula, a symbol indicates a bonding position.

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 benzimidazole substituents, two pyridine substituents may be substituted with benzimidazole substituents (that is, n ═ 2), or any pyridine substituent may be substituted with benzimidazole substituents and R may be substituted with benzimidazole substituents¹¹～R¹⁸Substituted for another pyridineSubstituted group (i.e., n ═ 1). Further, R in the formula (ETM-2-1) may be substituted with a benzimidazole-based substituent¹¹～R¹⁸At least one of R and¹¹～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). In addition, in the formula(ETM-12-1) wherein R¹¹～R¹⁸Is bonded to phi as the 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 is not only the above-mentioned examples, but also the following structural formulae are exemplified. In addition, R in the following structural formula is hydrogen, methyl, ethyl, isopropyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenyl or terphenyl independently. In addition, in each structural formula, a indicates 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, 9,9' -difluoro-bis (1, 10-phenanthrolin-5-yl), 2, 9-dimethyl-4, 7-biphenyl-1, 10-phenanthroline (bathocuproine), 1, 3-bis (2-phenyl-1, 10-phenanthrolin-9-yl) benzene, a compound represented by the following structural formula, or 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 general formula (ETM-13).

In the formula, R¹～R⁶Each independently is hydrogen, fluorine, alkyl, cycloalkyl, aralkyl, alkenyl, cyano, alkoxy or aryl, M is Li, Al, Ga, Be or Zn, and n is an integer of 1 to 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 >

The thiazole derivative is, for example, a compound represented by the following formula (ETM-14-1).

Phi- (thiazole 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 a "thiazole substituent" or a "benzothiadiazole substituent" is a substituent in which a pyridyl group in the "pyridine substituent" of the formula (ETM-2), the formula (ETM-2-1) or the formula (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. In the following structural formula, a symbol indicates a bonding position.

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, in the formula (ETM-2-1) or (ETM-2-2) described in the bonding of two pyridine substituent form, but when they are substituted for thiazole substituent (or benzothiazole substituent), can be substituted by thiazole substituent Two pyridine substituents (i.e., n ═ 2) are substituted with a substituent (or a substituent of the benzothizole series), and either one of the pyridine substituents may be substituted with a substituent of the thiazole series (or a substituent of the benzothizole series) and R may be substituted with a substituent of the thiazole series¹¹～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～R¹⁸At least one of R and¹¹～R¹⁸substituted "pyridine-based substituents".

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

In the electron transport layer or the electron injection layer, a substance that can reduce a material forming the electron transport layer or the electron injection layer may be further included. 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 of 2.36eV), K (work function of 2.28eV), Rb (work function of 2.16eV), and Cs (work function of 1.95eV), and alkaline earth metals such as Ca (work function of 2.9eV), Sr (work function of 2.0 to 2.5eV), and Ba (work function of 2.52eV), and particularly preferable substances have a work function of 2.9eV or less. Among these, K, Rb or Cs is a more preferable alkali metal as the reducing substance, Rb or Cs is more preferable, and Cs is most preferable. The alkali metal has particularly high reducing power, and the addition of a relatively small amount of the alkali metal to a material for forming the electron transporting layer or the electron injecting layer can improve the emission luminance of the organic EL element or prolong the life thereof. 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, Cs and K, Cs and Rb, or Cs and Na and K is particularly preferable. By including Cs, the reduction ability can be efficiently exhibited, and by adding Cs to a material for forming an electron transport layer or an electron injection layer, the emission luminance of an organic EL element can be improved or the lifetime thereof can be prolonged.

< 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 this, for example, a method of doping a minute amount of lithium, cesium, or magnesium into 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 thereto.

Further, the following preferable examples are listed: metals such as platinum, gold, silver, copper, iron, tin, aluminum, and indium, or alloys using these 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 alone to form 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 oxide, 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 EL 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 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 set to +50 ℃ to +400 ℃ in the boat heating temperature and 10 degrees of vacuum ^-6Pa～10^-3Pa, a deposition rate of 0.01 nm/sec to 50 nm/sec, a substrate temperature of-150 ℃ to +300 ℃, and a film thickness of 2nm to 5 μm.

Next, as an example of a method for manufacturing an organic EL element, a method for manufacturing 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, and a cathode will be described. 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. A target organic EL element is obtained by co-evaporating a host material and a dopant material on the thin film to form a thin film as a light-emitting layer, 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 EL 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 dc voltage is applied to the organic EL 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 EL 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 an arbitrary waveform.

< example of application of organic electroluminescent element >

The present invention is also applicable to a display device including an organic EL element, an illumination device including an organic EL element, and the like.

The display device or the lighting device including the organic EL element can be manufactured by a conventional method such as connecting the organic EL element of this embodiment to a conventional driving device, and can be driven by a conventional driving method such as direct current driving, pulse driving, or alternating current 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 panel (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 panel, 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 needs to 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: for example, a lighting device for indoor lighting, a backlight for a liquid crystal display device, and the like (see, for example, japanese patent laid-open nos. 2003-257621, 2003-277741, and 2004-119211). 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 the organic field effect transistor 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 and drain electrodes/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 and drain electrode/insulator layer/gate electrode

(4) Substrate/source and drain electrodes/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, or 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 for the organic thin film solar cell may be appropriately selected for use in combination.

[ examples ]

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples. First, a synthesis example of the polycyclic aromatic compound will be described below.

Synthesis example (1): synthesis of Compound (1-901)

Compound (I-1) (3.05g, 10mmol), compound (I-2) (3.35g, 12mmol), potassium carbonate (4.10g, 30mmol), bis (di-tert-butyl (4-dimethylaminophenyl) phosphine) dichloropalladium (II) (Pd-132: 0.0783g, 0.1mmol) and tetrabutylammonium bromide (TBAB: 0.97g, 3mmol) were placed in a flask under a nitrogen atmosphere, toluene (30ml) and distilled water (15ml) were added, and heating and refluxing were performed for 2 hours. The precipitated solid was subjected to suction filtration, washed with water and heptane, and the obtained crude product was purified by means of a short column of silica gel (eluent: chlorobenzene), whereby compound (1-901) was obtained as a white solid (yield: 0.56 g).

Synthesis example (2): synthesis of Compound (1-902)

Compound (I-3) (3.08g, 10mmol), compound (I-2) (3.35g, 12mmol), potassium carbonate (4.08g, 30mmol), bis (di-tert-butyl (4-dimethylaminophenyl) phosphine) dichloropalladium (II) (Pd-132: 0.0775g, 0.1mmol) and tetrabutylammonium bromide (TBAB: 1.00g, 3mmol) were placed in a flask under a nitrogen atmosphere, toluene (30ml) and distilled water (15ml) were added, and heating and refluxing were carried out for 14 hours. The precipitated solid was subjected to suction filtration, washed with water and heptane, and the obtained crude product was purified by means of a short column of silica gel (eluent: chlorobenzene), whereby compound (1-902) was obtained as a white solid (yield: 1.27 g).

By appropriately changing the compound as a raw material, another polycyclic aromatic compound of the present invention can be synthesized by the method according to the above synthesis example.

Next, examples of the organic EL device using the compound of the present invention are shown in order to explain the present invention in more detail, but the present invention is not limited to the examples.

< evaluation of vapor deposition type organic EL element >

Organic EL elements of example 1, example 2 and comparative example 1 were prepared and measured as 1000cd/m²Driving voltage (V) and external quantum efficiency (%) which are characteristics in light emission.

The quantum efficiency of a light-emitting element is an internal quantum efficiency, which indicates a ratio of external energy injected into a light-emitting layer of the light-emitting element in the form of electrons (or holes) to be converted into photons purely. On the other hand, the external quantum efficiency is calculated based on the amount of photons emitted to the outside of the light-emitting element, and since a part of photons generated in the light-emitting layer is continuously absorbed or reflected inside the light-emitting element and is not emitted to the outside of the light-emitting element, the external quantum efficiency is lower than the internal quantum efficiency.

The external quantum efficiency was measured as follows. The luminance of the element was set to 1000cd/m by applying a voltage/current generator R6144 manufactured by Edwardten test (Advantest) ²To make the element emit light. The spectral radiance in the visible light region was measured from the direction perpendicular to the light-emitting surface using a spectral radiance meter SR-3AR manufactured by TOPCON (TOPCON). Assuming that the light-emitting surface is a perfect diffusion surface, the number obtained by dividing the value of the spectral emission luminance of each measured wavelength component by the wavelength energy and multiplying by pi is the number of photons at each wavelength. Then, the number of photons is integrated in the observed full wavelength region as the total number of photons released from the element. The number of carriers (carriers) injected into the device is determined as a value obtained by dividing the applied current value by the elementary charge (elementary charge), and the number of total photons released from the device is determined as the external quantum efficiency by dividing the number of carriers injected into the device.

The material composition of each layer in the organic EL devices of example 1, example 2, and comparative example 1 is shown in table 1 below.

[ Table 1]

In Table 1, "HI" is N⁴,N^4'-diphenyl-N⁴,N^4'-bis (9-phenyl-9H-carbazol-3-yl) - [1,1' -biphenyl]-4,4 '-diamine, "HAT-CN" is 1,4,5,8,9, 12-hexaazatriphenylhexacarbonitrile, "HT-1" is N- ([1,1' -biphenyl)]-4-yl) -9, 9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine, "Host material (Host) 1" is 9-phenyl-10- (4-phenylnaphthalen-1-yl) anthracene, "ET-1" is 9- (4'- (ditrimethylphenylboryl) - [1,1' -binaphthyl ]-4-yl) -9H-carbazole. The chemical structure is shown below together with "Dopant (Dopant) 1".

< example 1 >

A glass substrate (manufactured by Opto Science) of 26mm by 28mm by 0.7mm obtained by polishing ITO formed to a thickness of 180nm by sputtering 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 Changzhou industry), and vapor deposition boats made of tungsten were placed with HI, HAT-CN, HT-1, host material 1, dopant 1, ET-1, compound (1-901), LiF, and aluminum, 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, HI was heated and vapor deposition was performed so that the film thickness became 65nm to form the hole injection layer 1. Next, HAT-CN was heated and vapor-deposited to a film thickness of 5nm to form the hole injection layer 2. Next, HT-1 was heated and vapor-deposited to a film thickness of 90nm to form a hole transport layer. Next, the host material 1 and the dopant 1 are simultaneously heated and vapor-deposited so that the film thickness becomes 25nm, thereby forming a light-emitting layer. The deposition rate was adjusted so that the mass ratio of the host material 1 to the dopant 1 was approximately 95 to 5. Subsequently, ET-1 was heated to form an electron transporting layer 1 by vapor deposition so that the film thickness became 20 nm. Then, the compound (1-901) was heated to form an electron transporting layer 2 by vapor deposition so that the film thickness became 10 nm. The deposition rate of each layer is 0.01nm/sec to 1 nm/sec. Then, LiF was heated to form a film thickness of 1nm, and vapor deposition was performed at a vapor deposition rate of 0.01nm/sec to 0.1nm/sec, and then aluminum was heated to form a cathode by vapor deposition to form a film thickness of 100nm, thereby obtaining an organic EL element. In this case, the deposition rate is adjusted to 0.1nm/sec to 10 nm/sec.

< example 2 >

An organic EL element was produced by the method according to example 1, except that the electron transport layer 2 was replaced with the compound (1-902).

< comparative example 1 >

An organic EL element was fabricated using the method according to example 1, except that the electron transport layer 2 was replaced with ET-1 (i.e., only ET-1 was used to form a 30nm electron transport layer).

A DC voltage was applied to the ITO electrode as an anode and the aluminum electrode as a cathode, and the concentration of the resultant was measured at 1000cd/m²The characteristics in light emission were as shown in Table 2And (6) obtaining the result. According to the results, by using the compound of the present invention as an electron transport layer, the driving voltage can be reduced.

[ Table 2]

< estimation of Electron transport Properties Using TOF measurement >

By measuring Time of flight (TOF), the electron mobility of a material can be measured separately from the electron injection region. The electron mobility was measured using a comparative compound (BPy-TP2) as a representative electron-injecting material having a bipyridyl group as a comparative example, and using a reference compound (BO2) having the same basic skeleton as the polycyclic aromatic compound of the present invention as a reference example.

The electron mobility at an applied electric field of 0.4MV/cm was 9.7X 10 in the comparative compound (BPy-TP2) ^-7cm²V.s, 1.6X 10 in the reference compound (BO2)^-6cm²V.s. From these results, it is understood that the basic skeleton portion of the polycyclic aromatic compound of the present invention has an excellent electron-transporting property as compared with the comparative compound. Therefore, it is expected that the polycyclic aromatic compound into which a nitrogen-containing substituent (the group of the formula (BiN)) for improving the electron-injecting property such as bipyridine is introduced into the basic skeleton will be an excellent material for an electron-transporting layer or an excellent material for an electron-injecting layer.

Although some of the compounds of the present invention were evaluated as materials for organic EL devices and showed excellent materials, those skilled in the art will understand that other compounds not evaluated also have the same basic skeleton and similar structures as a whole.

[ industrial applicability ]

In the present invention, by introducing a nitrogen-containing substituent of formula (Bi — N) into a polycyclic aromatic compound of formula (1) in which a plurality of aromatic rings are linked by a boron atom, an oxygen atom, or the like, a material for an electron transport layer or a material for an electron injection layer having high electron injection properties and electron mobility can be provided, and thus an organic device having a low driving voltage, for example, an organic EL element can be produced.

Claims

1. A polycyclic aromatic compound which is a monomer represented by the following general formula (1) or a polymer having a plurality of structures represented by the following general formula (1),

at least one hydrogen in the polycyclic aromatic compound may be substituted with cyano, halogen or deuterium.

2. The polycyclic aromatic compound according to claim 1,

at least one of the A ring, B ring, C ring, D ring, E ring, and the fused ring may be substituted with a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group, a substituted or unsubstituted diarylboryl group to which two substituted or unsubstituted aryl groups may be bonded via a single bond or a linking group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, or a substituted silyl group,

the A, B and C rings have 5-or 6-membered rings bonded in common to the condensed bicyclic structure comprising the central element "B" and two elements "O" in the center of formula (1),

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

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

any "-C (-R) ═ in the a ring, the b ring, and the C ring may be substituted with" -N ═ and any "-C (-R) ═ C (-R) -" may be substituted with "-N (-R) -", "-O-", or "-S-", and R of said "-C (-R) ═ and said" -C (-R) ═ C (-R) - "is R in formula (2)¹～R¹¹R of the "-N (-R) -" is aryl, alkyl or cycloalkyl,

R¹～R¹¹each independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl to which two aryl groups may be bonded via a single bond or a linking group, alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl, at least one of which may be substituted by aryl, heteroaryl, alkyl or cycloalkyl,

R¹～R¹¹May be bonded to each other and together with the a-ring, the b-ring or the c-ring form an aryl ring or a heteroaryl ring, at least one hydrogen in the formed ring may be substituted by an aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl to which both aryl groups may be bonded via a single bond or a linking group, an alkyl, cycloalkyl, alkoxy, aryloxy, triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl or alkylbicycloalkylsilyl, at least one of which may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group,

R⁷and R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

at least one hydrogen of the D ring, the E ring and the fused ring may be substituted by an aryl group, a heteroaryl group, a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, a diarylboron group to which two aryl groups may be bonded via a single bond or a linking group, an alkyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, a triarylsilyl group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group or an alkylbicycloalkylsilyl group, at least one hydrogen of which may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group,

at least one hydrogen in the polycyclic aromatic compound may be substituted with cyano, halogen or deuterium,

at least one of the a-ring, the b-ring, the c-ring, the formed ring, aryl and heteroaryl in the compound or structure represented by the formula (2) may be condensed with at least one cycloalkane having 3 to 24 carbon atoms, wherein at least one hydrogen in the cycloalkane may be substituted with an aryl having 6 to 30 carbon atoms, a heteroaryl having 2 to 30 carbon atoms, an alkyl having 1 to 24 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms, and at least one-CH in the cycloalkane may be substituted with an aryl having 6 to 30 carbon atoms, an alkyl having 2 to 30 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms ₂-may be substituted by-O-, and,

4. The polycyclic aromatic compound according to claim 3,

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

ring a, ring b, and ring cAny of "-C (-R) ═ may be substituted with" -N ═ and any of "-C (-R) ═ C (-R) -" may be substituted with "-N (-R) -", "-O-", or "-S-", and R of said "-C (-R) ═ and said" -C (-R) ═ C (-R) - "is R in formula (2)¹～R¹¹Wherein R of the "-N (-R) -" is aryl having 6 to 10 carbon atoms, alkyl having 1 to 5 carbon atoms or cycloalkyl having 5 to 10 carbon atoms,

R¹～R¹¹independently hydrogen, aryl group having 6 to 30 carbon atoms, heteroaryl group having 2 to 30 carbon atoms, diarylamino group in which aryl group is aryl group having 6 to 12 carbon atoms, diarylboron group in which aryl group is aryl group having 6 to 12 carbon atoms and two aryl groups may be bonded via a single bond or a linking group, alkyl group having 1 to 24 carbon atoms, cycloalkyl group having 3 to 24 carbon atoms, alkoxy group having 1 to 24 carbon atoms, aryloxy group having 6 to 30 carbon atoms, triarylsilyl group in which aryl group is aryl group having 6 to 12 carbon atoms, trialkylsilyl group in which alkyl group is alkyl group having 1 to 6 carbon atoms, at least one hydrogen of them may be substituted by alkyl group having 1 to 12 carbon atoms or cycloalkyl group having 3 to 16 carbon atoms,

R¹～R¹¹Wherein adjacent groups in the (a) ring, the (b) ring or the (c) ring may be bonded to each other to form an aryl ring having 9 to 16 carbon atoms or a heteroaryl ring having 6 to 15 carbon atoms, at least one hydrogen in the ring may be substituted by an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, a diarylamino group in which the aryl group is an aryl group having 6 to 12 carbon atoms, a diarylboron group in which the aryl group is an aryl group having 6 to 12 carbon atoms and both of the aryl groups may be bonded via a single bond or a linking group, an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group having 3 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, a triarylsilyl group in which the aryl group is an aryl group having 6 to 12 carbon atoms, or a trialkylsilyl group in which the alkyl group has 1 to 6 carbon atoms, and at least one hydrogen in the above groups may,

R⁷and R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

at least one hydrogen of the D ring, the E ring and the fused ring may be substituted by an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, a diarylamino group in which the aryl group is an aryl group having 6 to 12 carbon atoms, a diarylboron group in which the aryl group is an aryl group having 6 to 12 carbon atoms and both aryl groups may be bonded via a single bond or a linking group, an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group having 3 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, a triarylsilyltriarylsilyl group in which the aryl group is an aryl group having 6 to 12 carbon atoms, or a trialkylsilyl group in which the alkyl group is an alkyl group having 1 to 6 carbon atoms, and at least one hydrogen of these may be substituted by an alkyl group having 1 to 12,

5. The polycyclic aromatic compound according to claim 3,

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

any of the "C (-R) ═ in the a ring, the b ring, and the C ring may be substituted with" -N ═ and any of the "C (-R) ═ C (-R) -" may be substituted with "-N (-R) -", "-O-", or "-S-", and R of the "C (-R) ═ C (-R) -" is R in the formula (2)¹～R¹¹Wherein R of the "-N (-R) -" is aryl having 6 to 10 carbon atoms, alkyl having 1 to 5 carbon atoms or cycloalkyl having 5 to 10 carbon atoms,

R¹～R¹¹independently hydrogen, aryl group having 6 to 16 carbon atoms, heteroaryl group having 2 to 20 carbon atoms, diarylamino group in which aryl group is aryl group having 6 to 10 carbon atoms, diarylboron group in which aryl group is aryl group having 6 to 10 carbon atoms and two aryl groups may be bonded via a single bond or a linking group, alkyl group having 1 to 12 carbon atoms, cycloalkyl group having 3 to 16 carbon atoms, alkoxy group having 1 to 6 carbon atoms, aryloxy group having 6 to 16 carbon atoms, triarylsilyl group in which aryl group is aryl group having 6 to 10 carbon atoms, trialkylsilyl group in which alkyl group is alkyl group having 1 to 4 carbon atoms, at least one hydrogen of them may be substituted by alkyl group having 1 to 4 carbon atoms or cycloalkyl group having 5 to 10 carbon atoms,

R¹～R¹¹Wherein adjacent groups in the (a) ring, the (b) ring or the (c) ring may be bonded to each other to form an aryl ring having 9 to 16 carbon atoms or a heteroaryl ring having 6 to 15 carbon atoms, at least one hydrogen in the ring may be substituted by an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a diarylamino group in which the aryl group is an aryl group having 6 to 10 carbon atoms, a diarylboron group in which the aryl group is an aryl group having 6 to 10 carbon atoms and both of the aryl groups may be bonded via a single bond or a linking group, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 16 carbon atoms, a triarylsilyl group in which the aryl group is an aryl group having 6 to 10 carbon atoms, or a trialkylsilyl group in which the alkyl group has 1 to 4 carbon atoms, and at least one hydrogen in the groups may be,

R⁷and R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

at least one hydrogen of the D ring, the E ring and the fused ring may be substituted by an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a diarylamino group in which the aryl group is an aryl group having 6 to 10 carbon atoms, a diarylboron group in which the aryl group is an aryl group having 6 to 10 carbon atoms and both aryl groups may be bonded via a single bond or a linking group, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 16 carbon atoms, a triarylsilyl group in which the aryl group is an aryl group having 6 to 10 carbon atoms, or a trialkylsilyl group in which the alkyl group is an alkyl group having 1 to 4 carbon atoms, and at least one hydrogen of these may be substituted by an alkyl group having 1 to,

6. The polycyclic aromatic compound according to claim 3,

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

any of the "C (-R) ═ in the a ring, the b ring, and the C ring may be substituted with" -N ═ and any of the "C (-R) ═ C (-R) -" may be substituted with "-N (-R) -", "-O-", or "-S-", and R of the "C (-R) ═ C (-R) -" is R in the formula (2) ¹～R¹¹Wherein R of the "-N (-R) -" is aryl having 6 to 10 carbon atoms, alkyl having 1 to 5 carbon atoms or cycloalkyl having 5 to 10 carbon atoms,

R¹～R¹¹independently represents hydrogen, 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 10 carbon atoms, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a triarylsilyl group in which the aryl group is an aryl group having 6 to 10 carbon atoms, or a trialkylsilyl group in which the alkyl group is an alkyl group having 1 to 4 carbon atoms, at least one hydrogen of these groups being substituted by an alkyl group having 1 to 4 carbon atoms,

R⁷and R⁸Can be bonded to form-O-,

in the case of the formula (BiN),

at least one hydrogen of the ring D, the ring E and the fused ring may be substituted with 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 10 carbon atoms, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a triarylsilyl group in which the aryl group is an aryl group having 6 to 10 carbon atoms, or a trialkylsilyl group in which the alkyl group is an alkyl group having 1 to 4 carbon atoms, and at least one hydrogen of these may be substituted with an alkyl group having 1 to 4 carbon atoms,

7. The polycyclic aromatic compound according to any one of claims 1 to 5, wherein the group represented by the formula (BiN) is a group represented by any one of the following formulae,

me in the structural formula represents methyl and represents bonding position.

8. Polycyclic aromatic hydrocarbon according to any one of claims 3 to 7An aromatic compound, wherein in the formula (2), R¹And R³，R⁴And R¹¹，R⁵And R¹⁰，R⁶And R⁹，R²、R⁴And R¹¹，R²、R⁵And R¹⁰Or R is²、R⁶And R⁹Is a group represented by the formula (BiN).

9. The polycyclic aromatic compound according to claim 1, which is represented by any one of the following structural formulae,

10. a material for organic devices, comprising the polycyclic aromatic compound according to any one of claims 1 to 9.

11. The material for organic devices according to claim 10, which is a material for organic electroluminescent elements, a material for organic field effect transistors, or a material for organic thin-film solar cells.

12. The material for organic devices according to claim 11, wherein the material for organic electroluminescent elements is a material for electron transport layers or a material for electron injection layers.

13. An organic electroluminescent element comprising: a pair of electrodes including an anode and a cathode; a light-emitting layer disposed between the pair of electrodes; and at least one of an electron transport layer and an electron injection layer disposed between the cathode and the light-emitting layer, wherein the at least one of the electron transport layer and the electron injection layer contains the material for organic devices according to claim 12.

14. The organic electroluminescent element according to claim 13, 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-based derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, carbazole derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, and hydroxyquinoline-based metal complexes.

15. The organic electroluminescent element according to claim 13 or 14, wherein at least one of the electron transport layer and the electron injection layer contains at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, oxides of alkali metals, oxides of alkaline earth metals, oxides of rare earth metals, halides of alkali metals, halides of alkaline 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.

16. The organic electroluminescent element according to any one of claims 13 to 15, wherein the light-emitting layer contains at least one selected from the group consisting of a polycyclic aromatic compound represented by the following general formula (6), a polycyclic aromatic compound represented by the following general formula (7), and a compound represented by the following general formula (8),

In the above-mentioned formula (6),

X¹and X²Independently of each other > O, > N-R, > C (-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R)₂R of (A) is hydrogen, aryl which may be substituted, alkyl which may be substituted or may be substitutedSaid R > N-R and said > C (-R)₂At least one of R of (A) may be bonded to at least one of the A, B and C rings through a linking group,

at least one of the A ring, the B ring, the C ring, the aryl group and the heteroaryl group in the compound represented by formula (6) may be condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane may be substituted, at least one-CH in the cycloalkane₂-may be substituted by-O-, and,

at least one hydrogen in the compound represented by formula (6) may be substituted with cyano, halogen, or deuterium;

in the above-mentioned formula (7),

X¹、X²and X³Independently of each other > O, > N-R, > C (-R) ₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R)₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, and additionally, said R > N-R and said > C (-R)₂At least one of R of (A) may be bonded to at least one of the A, B and C rings through a linking group,

at least one hydrogen in the compound represented by formula (7) may be substituted with cyano, halogen, or deuterium;

in the above-mentioned formula (8),

X¹and X²Independently of each other > O, > N-R, > C (-R)₂R > N-R is aryl which may be substituted, heteroaryl which may be substituted, alkyl which may be substituted or cycloalkyl which may be substituted, said > C (-R) ₂R of (a) is hydrogen, optionally substituted aryl, optionally substituted alkyl or optionally substituted cycloalkyl, and additionally, said R > N-R and said > C (-R)₂At least one of R of (A) and (B) may be bonded to at least one of the A ring and the B ring through a linking group,

R⁴and R⁷Independently represents hydrogen, 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, an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms,

17. A display device or a lighting device comprising the organic electroluminescent element according to any one of claims 13 to 16.