JP2023049580A - Polycyclic aromatic compound - Google Patents

Abstract

SOLUTION: There is provided a polycyclic aromatic compound having a structure comprising one or two or more structural units represented by a following formula (1): (wherein, A ring, B ring and C ring are a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring, Y is>B-,>P-,>P(=O)- or >P(=S)-, X is>C(-RX1)-,>N- or>Si(-RX3)-, RX1 and RX3 are a substituted or unsubstituted aryl or the like, Z is>N-RZ2 or the like, RZ2 is a substituted or unsubstituted aryl or a substituted or unsubstituted heteroaryl or the like, L represents a linking group), which is useful as a material for an organic device such as an organic electroluminescent element.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a polycyclic aromatic compound, an organic device using the same, such as an organic electroluminescent device, an organic field effect transistor, and an organic thin film solar cell, as well as a display device and a lighting device.

Conventionally, display devices using light-emitting elements that emit electroluminescence have been studied in various ways because they can be reduced in power consumption and thickness. Further, organic electroluminescence elements made of organic materials can be easily reduced in weight and increased in size. has been actively investigated. In particular, the development of organic materials that emit light in one of the three primary colors of light, such as blue and green, and the ability to transport electrons and holes (potentially becoming semiconductors and superconductors). The development of materials has been actively researched, regardless of whether they are high-molecular compounds or low-molecular-weight compounds.

An organic EL element has a structure comprising a pair of electrodes consisting of an anode and a cathode, and one or more layers interposed between the pair of electrodes and containing an organic compound. Layers containing organic compounds include light-emitting layers and charge transport/injection layers that transport or inject charges such as holes and electrons. Various organic materials suitable for these layers have been developed.

Currently, three types of luminescent materials are used for the luminescent layer: fluorescent materials, phosphorescent materials, and thermally activated delayed fluorescence (TADF) materials. For example, fluorescent materials such as improved azaborine derivatives have been reported (Patent Document 1), and phosphorescent materials such as noble metal complexes having multidentate ligands have been developed (Patent Document 2). Carbazonitrile compounds and the like have been developed as delayed fluorescence (TADF) materials (Non-Patent Document 1).

In devices using either material, a material with a high lowest excited singlet energy or lowest excited triplet energy is used in the adjacent layer of the emitting layer or the host layer to prevent energy leakage from the emitting layer or surrounding layers, which leads to a decrease in efficiency. used for

WO 2015/102118 JP 2014-239225 A

Nature Vol.492 13 December 2012

As described above, various materials have been developed for use in organic EL devices. However, in order to increase options for organic EL device materials, it is desirable to develop materials that are composed of compounds that are different from conventional materials. It is rare. In addition, Patent Document 1 reports a polycyclic aromatic compound containing boron and an organic EL device using the compound. There is a need for layer materials and peripheral layer materials.

As a result of intensive studies to solve the above problems, the present inventors succeeded in producing a novel polycyclic aromatic compound, and found that this compound is effective as a material having higher singlet energy and triplet energy. I found Then, for example, such a polycyclic aromatic compound is used as a host material or a material of a layer adjacent to the light emitting layer, and a compound having a smaller triplet energy than that is used as a dopant material. A light emitting layer is arranged between a pair of electrodes. The present inventors have found that an excellent organic EL device can be obtained by constructing an organic EL device by using That is, the present invention provides the following polycyclic aromatic compounds, organic device materials, etc. containing the following polycyclic aromatic compounds.

<1> A polycyclic aromatic compound having a structure consisting of one or more structural units represented by the following formula (1);

In formula (1),
A ring, B ring and C ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,
Y is >B-, >P-, >P(=O)- or >P(=S)-;
X is >C(-R ^x1 )-, >N- or >Si(-R ^x3 )-,
R ^X1 and R ^X3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl;
Z is >C(-R ^Z1 ) ₂ , >N-R ^Z2 , >O, >Si(-R ^Z3 ) ₂ or >S;
R ^Z1 , R ^Z2 and R ^Z3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl; forming a ring together with the bonding element and the B ring or C ring, with the proviso that two R ^Z1 may be bonded to each other and two R ^Z3 may be bonded to each other;
L is a linking group having the shortest number of atoms of 1 to 4 linking the A ring and Y,
L may be bonded to the A ring via a linking group or a single bond,
At least one hydrogen in the structure may be replaced with deuterium, cyano or halogen.

<2> The polycyclic aromatic compound according to <1>, wherein the structure comprises one structural unit represented by formula (1).
<3> The polycyclic aromatic compound according to <1> or <2>, wherein ring A, ring B and ring C are all substituted or unsubstituted benzene rings.

<4> L is >C(-R ^L1 ) ₂ , >NR ^L2 , >O, >Si(-R ^L3 ) ₂ , >S, >C=CR ^L1 ₂ , >C=NR ^L2 , > C=O, >C=S, -φ-, -φ-C(-R ^L1 ) ₂ -, -φ-N(-R ^L2 )-, -φ-O-, -φ-Si(-R ^L3 ) ₂ -, -φ-S-, -φ-C (=CR ^L1 ₂ )-, -φ-C (=NR ^L2 )-, -φ-C (=O)- or -φ-C (=S ) - and
R ^L1 , R ^L2 and R ^L3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl, and are the same may be bonded to each other ^, and at least one of R ^L1 , R ^{L2 ,} and at least one of R ^L3 are each linked by a linking group or a single bond to ring A or may be bound to at least one of φ,
φ is a substituted or unsubstituted arylene or a substituted or unsubstituted heteroarylene, and the arylene and the heteroarylene both have bonds to two adjacent ring-constituting atoms;
The polycyclic aromatic compound according to any one of <1> to <3>.

<5> The polycyclic aromatic compound according to <4>, wherein L is >NR ^L2 .
<6> The polycyclic aromatic compound according to <4>, wherein L is 1,2-phenylene.
<7> X is >N-,
The polycyclic aromatic compound according to any one of <1> to <6>, wherein Z is >NR ^Z2 , >O, or >S.
<8> The polycyclic aromatic compound according to any one of <1> to <7>, wherein Y is B.

<9> The polycyclic aromatic compound according to <1>, represented by any one of the following formulas.

<10> The polycyclic aromatic compound according to <1>, represented by the following formula.

<11> An organic device material containing the polycyclic aromatic compound according to any one of <1> to <10>.
<12> The polycyclic aromatic compound according to any one of <1> to <10>, which has a pair of electrodes consisting of an anode and a cathode and an organic layer disposed between the pair of electrodes, wherein the organic layer is <1> to <10>. An organic electroluminescence device containing
<13> The organic electroluminescence device according to <12>, wherein the organic layer is a light-emitting layer.
<14> The organic electroluminescence device according to <13>, wherein the light-emitting layer contains the polycyclic aromatic compound as a host material and a dopant material.
<15> The organic electroluminescence device according to <12>, wherein the organic layer is an electron transport layer.
<16> The organic electroluminescence device according to <12>, wherein the organic layer is a hole transport layer.
<17> A display device or lighting device comprising the organic electroluminescence device according to any one of <12> to <16>.

According to a preferred embodiment of the present invention, by preparing an organic EL device using the novel polycyclic aromatic compound as, for example, a host material in the light-emitting layer, one component of the host material, or a component of a layer adjacent to the light-emitting layer, An organic EL device excellent in quantum efficiency and device life can be provided.

1 is a schematic cross-sectional view showing an organic EL element according to this embodiment; FIG.

The present invention will be described in detail below. Although the constituent elements described below may be described based on representative embodiments and specific examples, the present invention is not limited to such embodiments. In the present specification, a numerical range represented by "-" means a range including the numerical values described before and after "-" as lower and upper limits.
In this specification, "hydrogen atom (H)" may be referred to as "hydrogen" in the description of structural formulas. Similarly, "carbon atom (C)" may be referred to as "carbon".
As used herein, the term "adjacent groups" means two groups respectively bonded to two adjacent atoms (two atoms directly bonded by covalent bonds) in the structural formula.

In the present specification, "Me" is methyl, "Et" is ethyl, "nBu" is n-butyl (normal butyl), "tBu" is t-butyl (tertiary butyl), "iBu" is isobutyl, and "secBu" is secondary butyl, "nPr" is n-propyl (normal propyl), "iPr" is isopropyl, "tAm" is t-amyl, "2EH" is 2-ethylhexyl, "tOct" is t-octyl, "Ph" is Phenyl, "Mes" for mesityl (2,4,6-trimethylphenyl), "Tf" for trifluoromethanesulfonyl, "TMS" for trimethylsilyl, and "D" for deuterium.
In this specification, the organic electroluminescence device is sometimes referred to as an organic EL device.

In this specification, chemical structures and substituents are sometimes represented by the number of carbon atoms. It refers to the number of carbon atoms in each group and does not refer to the total number of carbon atoms in the chemical structure and substituents, or the total number of carbon atoms in the substituent and substituents. For example, “substituent B having Y carbon atoms and substituted with substituent A having X carbon atoms” means that “substituent B having Y carbon atoms” is substituted with “substituent A having X carbon atoms”. However, the carbon number Y is not the total carbon number of the substituents A and B. Further, for example, “substituent B having Y carbon atoms and substituted with substituent A” means that “substituent B having Y carbon atoms” is substituted with “substituent A (with no carbon number limitation)”. However, the carbon number Y is not the total carbon number of the substituents A and B.

Substituents herein may be substituted with additional substituents. For example, a particular substituent may be described as "substituted or unsubstituted." This means that the particular substituent may or may not be substituted with at least one further substituent. In the same sense, it may be said to be "optionally substituted". In the present specification, the specific substituent at this time may be referred to as the "first substituent", and the additional substituent may be referred to as the "second substituent".

1. Polycyclic Aromatic Compound of the Present Invention The polycyclic aromatic compound of the present invention is a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1).

The present inventors have found that the polycyclic aromatic compounds of the present invention, in which aromatic rings are linked by heteroatoms such as boron, phosphorus, oxygen, nitrogen, and sulfur, have a large HOMO-LUMO gap (bandgap Eg in thin films) and high It was found to have triplet energy. This is because the 6-membered ring containing a heteroatom has low aromaticity, which suppresses the reduction of the HOMO-LUMO gap accompanying the extension of the conjugated system, and suppresses the extension of the conjugated system by utilizing the strain in the molecule. It is considered that the reason for this is that a large HOMO-LUMO gap can be obtained.

In addition, the polycyclic aromatic compound containing a hetero element according to the present invention can be used as a material having high triplet energy in host compounds and light-emitting layers of phosphorescent organic EL devices and organic EL devices utilizing thermally activated delayed fluorescence. It is also useful as an adjacent electron-blocking layer (electron-blocking layer), hole-blocking layer (hole-blocking layer), electron-transporting layer, or hole-transporting layer. In addition, these polycyclic aromatic compounds can arbitrarily move the HOMO and LUMO energies by introducing substituents, so it is possible to optimize the ionization potential and electron affinity according to the surrounding materials. .

<Ring Structure of Structural Unit Represented by Formula (1)>
In formula (1), "A" to "C" within the circle are symbols indicating the ring structure indicated by the circle.

A ring, B ring and C ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring. All of A-ring to C-ring form a divalent group having bonds at two carbon atoms adjacent to each other on the aryl or heteroaryl ring in the structure.

In the substituted or unsubstituted aryl ring or substituted or unsubstituted heteroaryl ring in the A ring, B ring and C ring of the structural unit represented by formula (1), "substituted or unsubstituted (substituted or unsubstituted )” is preferably at least one substituent selected from the group of substituents Z described later.

The polycyclic aromatic compound of the present invention contains, in the molecule, a first "XY-containing ring structure" formed from two carbons in the A ring, X, Y and L, and two carbons in the B ring, Z and C It has a second "XY-containing ring structure" formed from two carbons in the ring. The second "XY ring-containing structure" is a 7-membered ring. In addition, the compound of the present invention has a "fused bicyclic structure" formed by a first "XY ring-containing structure" and a second "XY ring-containing structure" which are condensed.

Here, the "XY ring structure" is a ring structure formed containing X and Y in formula (1), and the "first XY ring structure" is X and L in the A ring, respectively. A "second XY-containing ring structure" is formed from two carbons o to each other, X, Y, and L, which are bonded to X and Z, respectively, in the B ring. , is formed from two carbons, X, Y and Z, in o-positions to each other that are attached to Y and Z, respectively, in the C ring. Similarly, in formula (2), the "XY-containing ring structure" is a ring structure formed by containing X and Y, and the "first XY-containing ring structure" Formed from one two carbons, X, Y and L, a "second XY-containing ring structure" includes two carbons o to each other in the b ring, two carbons o to each other in the c ring, X , Y and Z.

Here, the “condensed bicyclic structure” means two saturated hydrocarbon rings composed of Y and X in formula (1), the “first XY-containing ring structure” and the “second XY ring structure” means a condensed structure. This “condensed bicyclic structure” further shares a bond with rings A to C in any one of the rings. That is, rings A to C are condensed with the above "condensed bicyclic structure". Thus, the polycyclic aromatic compound of the present invention has a polycyclic structure in which at least five rings are condensed.

For example, each of the A to C rings independently has a "6-membered ring sharing a bond with the condensed bicyclic structure", that is, a 6-membered (preferably benzene ring c) condensed to the condensed bicyclic structure. be able to. Further, "the aryl ring or heteroaryl ring (which is the A ring) has this 6-membered ring" means that the A ring is formed only by this 6-membered ring, or that the 6-membered ring is included. It means that the A ring is formed by further condensing another ring and the like to this 6-membered ring. In other words, the “aryl ring or heteroaryl ring having a 6-membered ring (which is the A ring)” as used herein means that the 6-membered ring constituting all or part of the A ring is condensed into a condensed bicyclic structure. means that The same description applies to the "B ring" and "C ring", and the same description applies to the "5-membered ring".

A structure having a benzene ring condensed to a condensed bicyclic structure in which all of the A to C rings of formula (1) are represented by the following formula (2), and the structural unit represented by formula (2) is represented by the formula ( It is a preferred example of the structural unit represented by 1).

Ring A, ring B and ring C in formula (1) respectively correspond to ring a and its substituent R a , ring ^b and its substituent R ^b and ring c and its substituent R ^c in formula (2). do. As described above, formula (2) corresponds to a structure having a 6-membered ring as a ring directly condensed with the above condensed bicyclic structure as rings A to C of formula (1). "Having" a 6-membered ring means that, as described later, for example, adjacent groups among the four substituents R ^a are bonded to form a ring with respect to the a ring which is a 6-membered ring. This is because, in some cases, a six-membered a-ring to which another ring is condensed corresponds to the A-ring. In this sense, the rings of Formula (1) are represented by capital letters A to C, while the rings of Formula (2) are represented by lower case letters a to c.

R ^a , R ^b and R ^c in formula (2) are each independently hydrogen or a substituent. This substituent includes at least one substituent selected from the group Z of substituents described below.

Adjacent groups among substituents R ^a , R ^b and R ^c on rings a, b and c in formula (2) are bonded together to form an aryl A ring or a heteroaryl ring may be formed, and the formed ring may be substituted with at least one substituent selected from the substituent group Z described below.

Therefore, in the polycyclic aromatic compound of formula (2), depending on the mutual bonding form of the substituents on rings a to c, for example, as shown in the following formula (2-fr), the ring structure constituting the compound is Change. A' ring and B' ring in the following formula correspond to A ring and B ring in formula (1), respectively. In addition, the c-ring can be similarly changed.

The A' ring in the above formula (2-fr) is an aryl ring or hetero ring formed together with the a ring by bonding adjacent groups among a plurality of substituents R ^a as described in formula (2). It represents an aryl ring (it can also be said to be a condensed ring formed by condensing another ring structure to the a ring). Similarly, the B' ring represents an aryl ring or heteroaryl ring formed together with the b ring by bonding adjacent groups among the multiple substituents R ^b (the b ring is fused with another ring structure). It can be said that it is a condensed ring formed by

The above formula (2-fr) is A′ formed by condensing a benzene ring, for example, a benzene ring, an indole ring, a pyrrole ring, a benzofuran ring, or a benzothiophene ring, to the benzene ring which is the a ring or the b ring. The condensed ring A' or condensed ring A' formed with ring or B' ring is naphthalene ring, carbazole ring, indole ring, dibenzofuran ring, or dibenzothiophene ring, respectively.

A more specific example of formula (2-fr) is shown below.

The above formula (2-fr-ex) is a specific example of formula (2-fr), and two adjacent R ^a in the a ring of formula (2) and formula (2) are bonded to form the a ring An example in which an aryl ring (naphthalene ring) is formed together with (benzene ring), and two adjacent R ^b in the b ring are bonded to form a heteroaryl ring (dibenzofuran ring) together with the b ring (benzene ring) is. All of the formed rings have a 6-membered ring (benzene ring a or b) sharing a bond with the condensed bicyclic structure described above. Optional substituents on the aryl rings A' and B' (rings A and B of formula (1)) are represented by n R's in addition to R ^a and R ^b , and the lower limit of n is 0. , and the upper limit of n is the maximum number of possible replacements (4). These explanations can be similarly applied to all forms other than the above-described specific examples, such as cases where the c ring is changed or other aryl rings or heteroaryl rings are formed.

Any “—C(—R)=” (wherein R is R a , R ^b or R ^c ) in the a ring, b ring, and c ring in the structural ^unit represented by formula (2) is A structural unit represented by a formula in which "--N=" is substituted is also given as a preferred example of the structural unit represented by formula (1). Examples of rings in which "-C(-R)=" in the a to c rings (benzene ring) of formula (2) are replaced with "-N=" include pyridine ring, pyrimidine ring, pyridazine ring, pyrazine ring, Other nitrogen-containing heteroaryl rings are mentioned. Examples in which the a-ring portion of formula (2) is a nitrogen-containing heteroaryl ring are shown below.

In addition, adjacent groups (adjacent R ^a , adjacent R ^b Alternatively, a structure in which adjacent R ^c ) bonds to form a heteroaryl ring (quinoline ring in the above formula) together with the above ring is also preferred. The formed ring may be further substituted (indicated by n R's below). This is as described above. Examples in which the a-ring portion of formula (2) is the above ring are shown below.

Other examples include the following.

The same applies to the case where other parts of the a-ring in formula (2) are replaced with "-N=", or the case where the b-ring or c-ring is changed.

Any "-C(-R)=C(-R)-" (wherein R is R ^a , R ^b and R ^c in the a to c rings in the structural unit represented by formula (2) ) is "-N(-R)-", "-O-", "-S-", "-C(-R) _2- ", "-Si(-R) _2- ", or "- A structural unit represented by a formula substituted with "Se-" is also mentioned as a preferred example of the structural unit represented by formula (1). "-C(-R)=C(-R)-" in the a to c rings (benzene ring) of formula (2) is "-N(-R)-", "-O-", "-S -", "-C(-R) ₂ -", "-Si(-R) ₂ -" or the ring substituted for "-Se-" include pyrrole ring, furan ring, thiophene ring, etc. nitrogen-containing/oxygen/sulfur heteroaryl ring (5-membered ring) and aryl ring (5-membered ring) of R of "-N(-R)-", R of "-C(-R) ₂ -" and R of "-Si(-R) ₂ -" are hydrogen, aryl, heteroaryl, alkyl, or cycloalkyl, wherein at least one hydrogen in said R is optionally substituted with alkyl or cycloalkyl.
Examples in which the a-ring portion of formula (2) is the above ring are shown below.

Further, "-C(-R)=C(-R)-" in the a to c rings (benzene ring) is "-N(-R)-", "-O-", "-S-", ^Adjacent groups (adjacent R _a , adjacent _R ^b or A structure in which R ^c ) is bonded to form a heteroaryl ring (a ring such as an indole ring, a benzofuran ring, or a benzothiophene ring) together with the above ring is also preferred.
Examples in which the a-ring portion of formula (2) is such a ring are shown below.

Other examples include:

Other parts of the a ring of formula (2) are "-N(-R)-", "-O-", "-S-", "-C(-R) ₂ -", "-Si(- The same applies to the case where it is replaced with R) ₂ -" or "--Se--" and the case where the b-ring and c-ring are changed.

<Description of L>
L is a divalent linking group, and the shortest number of atoms between two bonding positions is 1-4. That is, in formula (1), L is a linking group having the shortest number of atoms of 1 to 4 linking the A ring and Y. Therefore, the number of atoms constituting the ring of the first XY ring-containing structure is 5 to 8. The shortest number of atoms connecting the A ring and Y is preferably 1 to 3, more preferably 1 or 2.

L is preferably >C(-R ^L1 ) ₂ , >NR ^L2 , >O, >Si(-R ^L3 ) ₂ , >S, >C=CR ^L1 ₂ , >C=NR ^L2 , >C =O, >C=S, -φ-, -φ-C(-R ^L1 ) ₂ -, -φ-N(-R ^L2 )-, -φ-O-, -φ-Si(-R ^L3 ) ₂ -, -φ-S-, -φ-C (=CR ^L1 ₂ )-, -φ-C (=NR ^L2 )-, -φ-C (=O)- and -φ-C (=S) -. In addition, although each of the above is bonded to ring A with one of the bonds and is bonded to ring Y with the other bond, any of the bonds may be bonded to either. Here, R ^L1 , R ^L2 and R ^L3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl. and two R ^L1 or R ^L3 that are bonded to the same element may be bonded to each other, and at least one of R ^L1 , R ^L2 and at least one of R ^L3 are each linked by a linking group or a single bond. It may be bonded to at least one of the A ring and φ. φ is substituted or unsubstituted arylene or substituted or unsubstituted heteroarylene, and φ has two adjacent ring-constituting atoms as bonding positions.

L is preferably >N-R ^L2 , >O, >S, -φ-, -φ-N(-R ^L2 )-, -φ-O- or -φ-S-, and in formula (2), Structures where L is >N-R ^L2 , >O, >S, -φ-, -φ-N(-R ^L1 )-, -φ-O- or -φ-S- are represented by formula (2 -a), formula (2-x), formula (2-t), formula (2-f), formula (2-af), formula (2-xf), formula (2-tf), formula (2- fa), formula (2-fx) and formula (2-ft).

φ in L is substituted or unsubstituted arylene or substituted or unsubstituted heteroarylene. Each of the above arylene and heteroarylene in φ has a bond on two adjacent ring-constituting atoms.
As the substituent when "substituted or unsubstituted" is used in the definition of φ, at least one substituent selected from the substituent group Z described below is preferable.

φ is preferably unsubstituted arylene or unsubstituted heteroarylene, more preferably unsubstituted 1,2-phenylene. Examples of structural units represented by formula (2) in which φ is unsubstituted arylene or unsubstituted heteroarylene are shown below.

<Description of Y>
Y is each independently >B-, >P-, >P(=O)-, >P(=S)-, >Al-, >Ga-, >As-, >C(-R) -, >Si(-R)-, or >Ge(-R)-, wherein R of >C(-R)-, R of >Si(-R)-, and >Ge(-R)- each R is independently optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkyl, or optionally substituted cycloalkyl. In addition, Y represents a partial structure having three bonds on one atom, for example, >P (= O) -, > P (= S) - Each of the three bonds indicated by P (phosphorus atom) It is in. Y is preferably >B-, >P-, >P(=O)-, or >P(=S)-, more preferably >B-.

<Description of X>
Each X in formula (1) is independently >N-, >C(-R ^x1 ) or >Si(-R ^x3 ), and R ^x1 and R ^x3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl. Substituents referred to as "substituted or unsubstituted" in the definition of R ^X1 and R ^X3 include at least one substituent selected from the group of substituents Z described below.

X is preferably >N- or >C(-R ^X1 ), more preferably >N-.

<Description of Z>
Z in formula (1) is >C(-R ^Z1 ) ₂ , >N-R ^Z2 , >O, >Si(-R ^Z3 ) ₂ or >S. Here, R ^Z1 , R ^Z2 and R ^Z3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl. or forms a ring with the bonding element and the ring of B ring or C ring. However, two R ^Z1 and two R ^Z3 may be bonded to each other. The structure in which R ^Z1 , R ^Z2 , and R ^Z3 form a ring together with the bonding element (C, N or Si) and the B ring or C ring includes any of the above groups (especially substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl), which are R ^Z1 , R ^Z2 , R ^Z3 bonding groups (linking groups or single bonds) to the B ring or C ring.

Linking groups include -CH ₂ -CH ₂ -, -CHR-CHR-, -CR ₂ -CR ₂ -, -CH=CH-, -CR=CR-, -C≡C-, -N(-R )-, -O-, -S-, -C(-R) ₂ -, -Si(-R) ₂ -, or -Se-. In addition, R of -CHR-CHR-, R of -CR ₂ -CR ₂ -, R of -CR=CR-, R of -N(-R)-, R of -C(-R) ₂ -, and -Si(-R) ₂ - are each independently hydrogen, aryl, heteroaryl, alkyl, alkenyl, alkynyl, or cycloalkyl, and at least one hydrogen in said R is alkyl or cycloalkyl may be substituted with Also, two adjacent R's may form a ring to form cycloalkylene, arylene, and heteroarylene.

As a linking group, a single bond, -CR=CR-, -N(-R)-, -O-, -S-, -C(-R) ₂ -, and -Si(-R) ₂ as a linking group -, and -Se- are preferred, and single bonds, -CR=CR-, -N(-R)-, -O-, -S- and -C(-R) ₂ - as linking groups are more preferred. , a single bond, and -CR=CR-, -N(-R)-, -O-, and -S- as linking groups are more preferred, and a single bond is most preferred.

The position where R ^Z2 and R ^Z3 are bonded to the B ring or C ring is not particularly limited as long as it is a bondable position. preferably.

Specific examples in which R ^Z2 of >N—R ^Z2 is bonded to ring B or C, which is a benzene ring, are shown below.

Z is preferably >NR ^Z2 , >O, or >S.

<Bond between rings>
Two rings that are directly bonded to each other by a single bond and two rings that are bonded to a common atom in formula (1) each further have an additional single bond or a linking group (collectively, a linking group (Also called). Specifically, the following structures are mentioned.
- The A ring and the B ring are further bonded by a bonding group other than X. (The A and B rings are bonded to a common atom in X.)
- φ and the A ring are linked by an additional linking group when L contains -φ- which is directly attached to the A ring.
- When L contains -φ- which is directly bonded to Y, φ and the C ring are linked by an additional linking group.
・When L contains -N(-R ^L1 )- directly bonded to the A ring, R ^L1 (R ^L1 is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl) and the A ring are linked by an additional linking group.
φ and R L1 when L is -φ-N(-R ^L1 )- (R ^L1 is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, ^substituted or unsubstituted alkyl or substituted or unsubstituted substituted cycloalkyl) is attached by an additional linking group.

For example, in formula (2), R ^a and R ^b bonded to the carbon atom adjacent to the carbon atom bonded to X may bond to each other to form a single bond or a linking group. In formula (2), R ^b and R ^c bonded to the carbon atom adjacent to the carbon atom bonded to Z may be bonded to each other to form a single bond or a linking group.

Further, in formulas (2-a) and (2-af), the a ring and the φ ring may be linked by an additional linking group. In formula (2-af), formula (2-xf) and formula (2-tf), c-ring and φ-ring may be bonded by an additional bonding group. In formula (2-fa), formula (2-fx) and formula (2-ft), R ^L1 is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted When it is a substituted cycloalkyl, the R ^L1 and φ ring may be attached by an additional linking group. The a-ring and φ-ring in formula (2-f), formula (2-fa), formula (2-fx) and formula (2-ft) may be linked by an additional linking group.

Linking groups include -CH ₂ -CH ₂ -, -CHR-CHR-, -CR ₂ -CR ₂ -, -CH=CH-, -CR=CR-, -C≡C-, -N(-R )-, -O-, -S-, -C(-R) ₂ -, -Si(-R) ₂ -, or -Se-. In addition, R of -CHR-CHR-, R of -CR ₂ -CR ₂ -, R of -CR=CR-, R of -N(-R)-, R of -C(-R) ₂ -, and -Si(-R) ₂ - are each independently hydrogen, aryl, heteroaryl, alkyl, alkenyl, alkynyl, or cycloalkyl, and at least one hydrogen in said R is alkyl or cycloalkyl may be substituted with Also, two adjacent R's may form a ring to form cycloalkylene, arylene, and heteroarylene.

As a linking group, a single bond, -CR=CR-, -N(-R)-, -O-, -S-, -C(-R) ₂ -, and -Si(-R) ₂ as a linking group -, and -Se- are preferred, and single bonds, -CR=CR-, -N(-R)-, -O-, -S- and -C(-R) ₂ - as linking groups are more preferred. , a single bond, and -CR=CR-, -N(-R)-, -O-, and -S- as linking groups are more preferred, and a single bond is most preferred.

The position where the two rings are bonded by the bonding group is not particularly limited as long as it is a bondable position, but it is preferable to bond at the most adjacent position. It is preferable that the ortho (2-position) positions are further bonded to each other based on the bonding position (1-position) of "N" (see the structural formula of formula (1)).

<When two groups bonded to the same atom are bonded to each other>
>C(-R ^Z1 ) _{2 ,} >Si(-R ^Z3 ) ₂ , -C(-R) ₂ -, ^Z1 , two R ^Z3 , and the other two R) may combine with each other to form a ring. It is sufficient that they are linked by a single bond or a linking group (collectively referred to as a linking group), and the linking group includes -CH ₂ -CH ₂ -, -CHR-CHR-, -CR ₂ -CR ₂ -, -CH=CH-, -CR=CR-, -C≡C-, -N(-R)-, -O-, -S-, -C(-R) ₂ -, -Si(-R) ₂ -, or -Se-, such as the following structures. In addition, R of -CHR-CHR-, R of -CR ₂ -CR ₂ -, R of -CR=CR-, R of -N(-R)-, R of -C(-R) ₂ -, and -Si(-R) ₂ - are each independently hydrogen, aryl optionally substituted with alkyl or cycloalkyl, heteroaryl optionally substituted with alkyl or cycloalkyl, or cycloalkyl optionally substituted alkyl, alkenyl optionally substituted with alkyl or cycloalkyl, alkynyl optionally substituted with alkyl or cycloalkyl, or cycloalkyl optionally substituted with alkyl or cycloalkyl . Also, two adjacent R's may form a ring to form cycloalkylene, arylene, and heteroarylene.

As a linking group, a single bond, -CR=CR-, -N(-R)-, -O-, -S-, -C(-R) ₂ -, and -Si(-R) ₂ as a linking group -, and -Se- are preferred, and single bonds, -CR=CR-, -N(-R)-, -O-, -S- and -C(-R) ₂ - as linking groups are more preferred. , a single bond, and -CR=CR-, -N(-R)-, -O-, and -S- as linking groups are more preferred, and a single bond is most preferred.

The position where the two R are bonded by the bonding group is not particularly limited as long as it is a bondable position, but it is preferable to bond at the most adjacent position. For example, when the two groups are phenyl, "C" in phenyl It is preferable to bond at the ortho (2-position) positions with respect to the bonding position (1-position) of or "Si" (see the structural formula above).

<Specific Description of Ring and Substituent>
Details of the rings and substituents described herein are set forth below.

The “aryl ring” is, for example, an aryl ring having 6 to 30 carbon atoms, preferably an aryl ring having 6 to 20 carbon atoms, an aryl ring having 6 to 16 carbon atoms, an aryl ring having 6 to 12 carbon atoms, or an aryl ring having 6 to 12 carbon atoms. Examples include aryl rings of numbers 6 to 10.

A specific “aryl ring” is, for example, a monocyclic benzene ring, a condensed bicyclic naphthalene ring, a condensed tricyclic acenaphthylene ring, fluorene ring, phenalene ring, phenanthrene ring, or anthracene ring. , condensed tetracyclic ring system such as triphenylene ring, pyrene ring or naphthacene ring, or condensed pentacyclic ring system such as perylene ring or pentacene ring.

The "heteroaryl ring" is, for example, a heteroaryl ring having 2 to 30 carbon atoms, preferably a heteroaryl ring having 2 to 25 carbon atoms, a heteroaryl ring having 2 to 20 carbon atoms, a heteroaryl ring having 2 to 15 carbon atoms, and a heteroaryl ring having 2 to 15 carbon atoms. An aryl ring, a heteroaryl ring having 2 to 10 carbon atoms, or the like. Further, the “heteroaryl ring” is, for example, a heterocyclic ring containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen in addition to carbon as ring-constituting atoms.

Specific "heteroaryl rings" include, for example, 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, phenoxathiine ring, phenoxazine ring, phenothiazine ring, phenazine ring, phenazacillin ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, naphthobenzofuran ring, thiophene ring, benzothiophene ring, isobenzothiophene ring, dibenzothiophene ring, naphthobenzothiophene ring, benzophosphole ring, dibenzophosphole ring, benzophosphole oxide ring, dibenzophosphole oxide ring, furazane ring, thianthrene ring, indolocarbazole ring, benzoindolocarbazole ring, dibenzoindolocarbazole ring, imidazoline ring, oxazoline ring and the like.

In the present specification, the substituent group Z is
aryl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl;
heteroaryl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl;
diarylamino optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl (the two aryls may be bonded to each other via a linking group);
diheteroarylamino optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl (two heteroaryls may be bonded to each other via a linking group) ,
arylheteroarylamino optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl (aryl and heteroaryl may be ),
diarylboryl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl (the two aryls may be bonded via a single bond or a linking group);
alkyl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl and cycloalkyl;
cycloalkyl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl;
alkoxy optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl and cycloalkyl;
It consists of aryloxy optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, alkyl and cycloalkyl, and substituted silyl.
The second substituent aryl in each group of the substituent group Z may be further substituted with aryl, heteroaryl, alkyl, or cycloalkyl. Similarly, the second substituent heteroaryl is aryl, It may be optionally substituted with heteroaryl, alkyl, or cycloalkyl.

As used herein, "aryl" is, for example, aryl having 6 to 30 carbon atoms, preferably aryl having 6 to 20 carbon atoms, aryl having 6 to 16 carbon atoms, aryl having 6 to 12 carbon atoms, or Aryl of numbers 6 to 10 and the like.

A specific “aryl” is, for example, a monocyclic phenyl, a bicyclic biphenylyl (2-biphenylyl, 3-biphenylyl, or 4-biphenylyl), a condensed bicyclic naphthyl (1-naphthyl or 2-naphthyl), tricyclic terphenylyl (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, or p-terphenyl- 4-yl), acenaphthylene-(1-, 3-, 4-, or 5-)yl, fluorene-(1-, 2-, 3-, 4-, or 9-)yl, which is a fused tricyclic system , phenalen-(1- or 2-)yl, phenanthrene-(1-, 2-, 3-, 4-, or 9-)yl, or anthracen-(1-, 2-, or 9-)yl, tetra The ring system quaterphenylyl (5′-phenyl-m-terphenyl-2-yl, 5′-phenyl-m-terphenyl-3-yl, 5′-phenyl-m-terphenyl-4-yl , or m-quaterphenyl), a fused tetracyclic ring system, triphenylene-(1- or 2-)yl, pyren-(1-, 2-, or 4-)yl, or naphthacene-(1-, 2 -, or 5-)yl, or perylene-(1-, 2-, or 3-)yl, or pentacene-(1-, 2-, 5-, or 6-)yl, which is a fused five-ring system and so on. Other examples include a monovalent group of spirofluorene.

The aryl as the second substituent includes aryl such as phenyl (specific examples are the groups described above), alkyl such as methyl (specific examples are groups described later), and cycloalkyl such as cyclohexyl or adamantyl. Structures substituted with at least one group selected from the group consisting of (specific examples are groups described later) are also included.
An example thereof is a group in which the 9-position of fluorenyl as the second substituent is substituted with aryl such as phenyl, alkyl such as methyl, or cycloalkyl such as cyclohexyl or adamantyl.

"Arylene" is, for example, arylene having 6 to 30 carbon atoms, preferably arylene having 6 to 20 carbon atoms, arylene having 6 to 16 carbon atoms, arylene having 6 to 12 carbon atoms, or arylene having 6 to 10 carbon atoms. Arylene and others.
A specific “arylene” is, for example, a divalent group obtained by removing one hydrogen from the above-mentioned “aryl” (monovalent group).

“Heteroaryl” is, for example, heteroaryl having 2 to 30 carbon atoms, preferably heteroaryl having 2 to 25 carbon atoms, heteroaryl having 2 to 20 carbon atoms, heteroaryl having 2 to 15 carbon atoms, or carbon Heteroaryl of numbers 2 to 10 and the like. “Heteroaryl” contains 1 or more, preferably 1 to 5, heteroatoms selected from oxygen, sulfur, nitrogen and the like as ring-constituting atoms in addition to carbon atoms.

Specific examples of "heteroaryl" 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, quinolinyl, isoquinolinyl, cinnolinyl, quinazolinyl, quinoxalinyl, phenanthrolinyl, phthalazinyl, napthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiinyl, phenoxazinyl, phenothiazinyl, phenazinyl, phenazacilinyl, indolizinyl, furanyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, naphthobenzofuranyl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, naphthobenzothienyl, benzophosphoryl, dibenzophosphoryl , a monovalent group of a benzophosphole oxide ring, a monovalent group of a dibenzophosphole oxide ring, furazanyl, thianthrenyl, indolocarbazolyl, benzoindolocarbazolyl, dibenzoindolocarbazolyl, imidazolinyl, or oxazolinyl and so on. Other examples include a spiro[fluorene-9,9'-xanthene] monovalent group, a spirobi[silafluorene] monovalent group, and a benzoselephene monovalent group.

The heteroaryl as the second substituent includes aryl such as phenyl (specific examples are the groups described above), alkyl such as methyl (specific examples are groups described later), and cyclohexyl or adamantyl. Structures substituted with at least one group selected from the group consisting of alkyl (specific examples are groups described later) are also included.
Examples thereof include groups in which the 9-position of carbazolyl as the second substituent is substituted with aryl such as phenyl, alkyl such as methyl, or cycloalkyl such as cyclohexyl or adamantyl. In addition, groups in which nitrogen-containing heteroaryl such as pyridyl, pyrimidinyl, triazinyl and carbazolyl are further substituted with phenyl or biphenylyl are also included in heteroaryl as the second substituent.

"Heteroarylene" is, for example, heteroarylene having 2 to 30 carbon atoms, preferably heteroarylene having 2 to 25 carbon atoms, heteroarylene having 2 to 20 carbon atoms, heteroarylene having 2 to 15 carbon atoms, or carbon Heteroarylene of numbers 2 to 10 and the like. Further, "heteroarylene" is, for example, a bivalent group such as a heterocyclic ring containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen in addition to carbon as ring-constituting atoms.
A specific “heteroarylene” is, for example, a divalent group obtained by removing one hydrogen from the above-mentioned “heteroaryl” (monovalent group).

"Diarylamino" is amino substituted with two aryls, and the above description of "aryl" can be referred to for details of this aryl.
"Diheteroarylamino" is amino substituted with two heteroaryls, and the above description of "heteroaryl" can be referred to for details of this heteroaryl.
"Arylheteroarylamino" is amino substituted with aryl and heteroaryl, and the details of this aryl and heteroaryl can be referred to the above description of "aryl" and "heteroaryl".

Two aryls in the diarylamino as the first substituent may be bonded to each other via a linking group, and two heteroaryls in the diheteroarylamino as the first substituent may be bonded to each other via a linking group. The aryl and heteroaryl of the arylheteroarylamino as the first substituent may be bonded to each other via a linking group. Here, the description "bonded via a linking group" means that two phenyls such as diphenylamino form a bond via the linking group as shown below. This explanation also applies to diheteroarylamino and arylheteroarylamino formed by aryl and heteroaryl.

Specific examples of the linking groups include >O, >N—R ^x , >C(—R ^x ) ₂ , >Si(—R ^x ) ₂ , >S, >CO, >CS, >SO, >SO ₂ , and >Se. Each R ^X is independently alkyl, cycloalkyl, aryl or heteroaryl, which may be substituted with alkyl, cycloalkyl, aryl or heteroaryl. In addition, R ^X in >C(-R ^X ) ₂ and >Si(-R ^X ) ₂ may be bonded via a single bond or a linking group X ^Y to form a ring. X ^Y is >O, >N-R ^Y , >C(-R ^Y ) ₂ , >Si(-R ^Y ) ₂ , >S, >CO, >CS, >SO, >SO ₂ , and >Se and each R ^Y is independently alkyl, cycloalkyl, aryl or heteroaryl, which may be substituted with alkyl, cycloalkyl, aryl or heteroaryl. However, when X ^Y is >C(-R ^Y ) ₂ and >Si(-R ^Y ) ₂ , the two R ^Y do not combine to form a further ring. Further examples of linking groups include alkenylene. Any hydrogen of said alkenylene may each independently be substituted with R ^X , each R ^X being independently alkyl, cycloalkyl, substituted silyl, aryl and heteroaryl, which are alkyl, cycloalkyl, It may be substituted with substituted silyl or aryl.

In the present specification, when simply described as "diarylamino", "diheteroarylamino" or "arylheteroarylamino", unless otherwise specified, "the two aryls of diarylamino are may be bonded via a linking group", "two heteroaryls of the diheteroarylamino may be bonded to each other via a linking group", and "the aryl and heteroaryl of the arylheteroarylamino may be bonded to each other via a linking group".

"Diarylboryl" is boryl substituted with two aryls, and the above description of "aryl" can be referred to for details of this aryl. The two aryls may also be a single bond or a linking group (e.g., -CH=CH-, -CR=CR-, -C≡C-, >NR, >O, >S, >C(-R ) ₂ , >Si(-R) ₂ , or >Se). Here, R of -CR=CR-, R of >NR, R of >C(-R) ₂ and R of >Si(-R) are aryl, heteroaryl, diarylamino, alkyl, alkenyl, alkynyl, cycloalkyl, alkoxy, or aryloxy, and at least one hydrogen in said R may be further substituted with aryl, heteroaryl, alkyl, alkenyl, alkynyl, or cycloalkyl. Also, two adjacent R's may form a ring to form cycloalkylene, arylene, and heteroarylene. For details of the substituents listed here, see the description of "aryl", "arylene", "heteroaryl", "heteroarylene" and "diarylamino" above, and "alkyl" and "alkenyl" below. , “alkynyl”, “cycloalkyl”, “cycloalkylene”, “alkoxy” and “aryloxy” descriptions can be cited. In addition, when simply described as "diarylboryl" in this specification, unless otherwise specified, "two aryls of diarylboryl may be bonded to each other via a single bond or a linking group." It is assumed that the explanation is added.

"Alkyl" may be either straight-chain or branched-chain, for example straight-chain alkyl having 1 to 24 carbon atoms or branched-chain alkyl having 3 to 24 carbon atoms, preferably alkyl having 1 to 18 carbon atoms ( 3 to 18 branched chain alkyl), C 1 to 12 alkyl (C 3 to 12 branched chain alkyl), C 1 to 6 alkyl (C 3 to 6 branched chain alkyl), carbon number Examples include alkyl of 1 to 5 (branched alkyl of 3 to 5 carbon atoms), alkyl of 1 to 4 carbon atoms (branched alkyl of 3 to 4 carbon atoms), and the like.

Specific "alkyl" include, for example, methyl, ethyl, n-propyl, isopropyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1,2-trimethylpropyl, 1,1,2 , 2-tetramethylpropyl, 1-ethyl-1,2,2-trimethylpropyl, n-butyl, isobutyl, s-butyl, t-butyl, 2-ethylbutyl, 1,1-dimethylbutyl, 3,3-dimethyl Butyl, 1,1-diethylbutyl, 1-ethyl-1-methylbutyl, 1-propyl-1-methylbutyl, 1,1,3-trimethylbutyl, 1-ethyl-1,3-dimethylbutyl, n-pentyl, isopentyl , neopentyl, t-pentyl (t-amyl), 1-methylpentyl, 2-propylpentyl, 1,1-dimethylpentyl, 1-ethyl-1-methylpentyl, 1-propyl-1-methylpentyl, 1-butyl -1-methylpentyl, 1,1,4-trimethylpentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 1,1-dimethylhexyl, 1-ethyl-1-methylhexyl, 1,1,5- trimethylhexyl, 3,5,5-trimethylhexyl, n-heptyl, 1-methylheptyl, 1-hexylheptyl, 1,1-dimethylheptyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, n-octyl, t-octyl (1,1,3,3-tetramethylbutyl), 1,1-dimethyloctyl, n-nonyl, n-decyl, 1-methyldecyl, n-undecyl, n-dodecyl, n- tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl, and the like.

For "alkenyl", the above description of "alkyl" can be referred to. Also includes groups in which two or more single bonds are substituted with double bonds (also called alkadien-yl or alkanetrien-yl).

For "alkynyl", the above description of "alkyl" can be referred to. Also included are groups in which two or more single bonds are replaced by triple bonds (also called alkadiyn-yl or alkanetriin-yl).

"Cycloalkyl" is, for example, cycloalkyl having 3 to 24 carbon atoms, preferably cycloalkyl having 3 to 20 carbon atoms, cycloalkyl having 3 to 16 carbon atoms, cycloalkyl having 3 to 14 carbon atoms, and cycloalkyl having 3 to 14 carbon atoms. cycloalkyl having 3 to 12 carbon atoms, cycloalkyl having 5 to 10 carbon atoms, cycloalkyl having 5 to 8 carbon atoms, cycloalkyl having 5 to 6 carbon atoms, cycloalkyl having 5 carbon atoms, and the like.

Specific "cycloalkyl" includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, or alkyls having 1 to 5 carbon atoms or 1 to 4 carbon atoms (especially methyl). substituted, norbornenyl, bicyclo[1.1.0]butyl, bicyclo[1.1.1]pentyl, bicyclo[2.1.0]pentyl, bicyclo[2.1.1]hexyl, bicyclo[3.1 .0]hexyl, bicyclo[2.2.1]heptyl, bicyclo[2.2.2]octyl, adamantyl, diamantyl, decahydronaphthalenyl, or decahydroazulenyl.

"Cycloalkylene" is, for example, cycloalkylene having 3 to 24 carbon atoms, preferably cycloalkylene having 3 to 20 carbon atoms, cycloalkylene having 3 to 16 carbon atoms, cycloalkylene having 3 to 14 carbon atoms, and cycloalkylene having 3 to 14 carbon atoms. cycloalkylene having 3 to 12 carbon atoms, cycloalkylene having 5 to 10 carbon atoms, cycloalkylene having 5 to 8 carbon atoms, cycloalkylene having 5 to 6 carbon atoms, cycloalkylene having 5 carbon atoms, and the like.
A specific “cycloalkylene” is, for example, a divalent group obtained by removing one hydrogen from the above-mentioned “cycloalkyl” (monovalent group).

"Alkoxy" is a group represented by "Alk-O- (Alk is alkyl)", and for details of this alkyl, the above description of "alkyl" can be cited.

"Aryloxy" is a group represented by "Ar--O-- (Ar is aryl)", and for details of this aryl, the above description of "aryl" can be cited.

"Substituted silyl" is, for example, silyl substituted with at least one of aryl, alkyl, and cycloalkyl, preferably triarylsilyl, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, or alkyl It is a dicycloalkylsilyl.

"Triarylsilyl" is a silyl group substituted with three aryls, and the above description of "aryl" can be referred to for details of this aryl.
A specific "triarylsilyl" is, for example, triphenylsilyl, diphenylmononaphthylsilyl, monophenyldinaphthylsilyl, or trinaphthylsilyl.

"Trialkylsilyl" is a silyl group substituted with three alkyls, and for details of this alkyl, the above description of "alkyl" can be cited.
Specific "trialkylsilyl" includes, for example, trimethylsilyl, triethylsilyl, tri-n-propylsilyl, triisopropylsilyl, tri-n-butylsilyl, triisobutylsilyl, tri-s-butylsilyl, tri-t-butylsilyl, ethyldimethylsilyl, n-propyldimethylsilyl, isopropyldimethylsilyl, n-butyldimethylsilyl, isobutyldimethylsilyl, s-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, n-propyldiethylsilyl, isopropyldiethylsilyl, n-butyldiethyl silyl, s-butyldiethylsilyl, t-butyldiethylsilyl, methyldi-n-propylsilyl, ethyldi-n-propylsilyl, n-butyldi-n-propylsilyl, s-butyldi-n-propylsilyl, t-butyldi-n-propylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, n-butyldiisopropylsilyl, s-butyldiisopropylsilyl, t-butyldiisopropylsilyl, and the like.

"Tricycloalkylsilyl" is a silyl group substituted with three cycloalkyls, and for details of this cycloalkyl, the above description of "cycloalkyl" can be cited.
A specific "tricycloalkylsilyl" is, for example, tricyclopentylsilyl or tricyclohexylsilyl.

A "dialkylcycloalkylsilyl" is a silyl group substituted with two alkyls and one cycloalkyl, and the details of the alkyl and cycloalkyl can be referred to the above explanations of "alkyl" and "cycloalkyl".

"Alkyldicycloalkylsilyl" is a silyl group substituted with one alkyl and two cycloalkyls, and the details of this alkyl and cycloalkyl can be referred to the above explanations of "alkyl" and "cycloalkyl" .

The substituents of the above structural units may be selected according to the use of the polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1). Preferably methyl, t-butyl, adamantyl, phenyl, o-tolyl, naphthyl, biphenylyl, terphenyl, diphenylamino, carbazolyl, dibenzofuranyl, dibenzothiophenyl, 3,5-di-carbazolylphenyl, carbazolyl-substituted phenyl, pyridyl, phenyl-substituted pyridyl, bipyridyl, piperidinyl, phenyl-substituted piperidinyl, pyrazinyl, phenyl-substituted pyrazinyl, triazinyl, 3,5-diphenyl-triazinyl, biphenyl-substituted triazinyl, carbazolyl-substituted triazinyl, cyano. When a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1) is used as a hole-transporting layer or a hole-transporting host, the substituents are diphenylamino and carbazolyl. , dibenzofuranyl, dibenzothiophenyl, 3,5-di-carbazolylphenyl, carbazolyl-substituted phenyl are more preferred. When used as an electron-transporting layer or electron-transporting host, the substituents are pyridyl, phenyl-substituted pyridyl, bipyridyl, piperidinyl, phenyl-substituted piperidinyl, pyrazinyl, phenyl-substituted pyrazinyl, triazinyl, 3,5-diphenyl-triazinyl, biphenyl-substituted triazinyl, Carbazolyl-substituted triazinyl, cyano is preferred. When used as host materials, the substituents are phenyl, naphthyl, biphenylyl, terphenyl, diphenylamino, carbazolyl, dibenzofuranyl, dibenzothiophenyl, 3,5-di-carbazolylphenyl, carbazolyl-substituted phenyl, pyridyl, phenyl Substituted pyridyl, bipyridyl, piperidinyl, phenyl-substituted piperidinyl, pyrazinyl, phenyl-substituted pyrazinyl, triazinyl, 3,5-diphenyl-triazinyl, biphenyl-substituted triazinyl, carbazolyl-substituted triazinyl are preferred.

R ^L1 , R ^L2 and R ^L3 in L are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl . R ^Z1 , R ^Z2 and R ^Z3 in Z are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl is. In R ^L1 , R ^L2 , R ^L3 , R ^Z1 , R ^Z2 and R ^Z3 , the substituents referred to as “substituted or unsubstituted” include aryl (optionally substituted with aryl, heteroaryl), hetero Examples include aryl (optionally substituted with aryl or heteroaryl), alkyl, cycloalkyl, or substituents represented by any of the following formulas.

<Structure Consisting of One or Two or More Structural Units>
The polycyclic aromatic compound of the present invention is a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1). A polycyclic aromatic compound having a structure consisting of one of the above structural units is a polycyclic aromatic compound represented by the formula explained above as the structural unit represented by formula (1). As the polycyclic aromatic compound having a structure consisting of two or more structural units represented by formula (1), polycyclic aromatic compounds represented by the above-described formulas as structural units represented by formula (1) It is a compound corresponding to multimers of group compounds. The multimer is preferably a 2- to 6-mer, more preferably a 2- to 3-mer, and particularly preferably a dimer. The multimer may be in a form having a plurality of the above unit structures in one compound, and any ring (A ring, B ring or C ring) contained in the above structural unit may be shared by a plurality of unit structures. It may be in a form in which any rings (A ring, B ring or C ring) included in the unit structure are condensed and bonded. In addition, the above unit structure may be in a form in which a plurality of units are bonded by a single bond, a linking group such as alkylene having 1 to 3 carbon atoms, phenylene, naphthylene, or the like. Among these, preferred is a form in which the ring is shared.

<Description of Substitution with Deuterium, Cyano, or Halogen>
At least one hydrogen in the polycyclic aromatic compounds of the present invention may be replaced with deuterium, cyano, or halogen. Halogen is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine.

<Specific examples of the polycyclic aromatic compound of the present invention>
Specific examples of the polycyclic aromatic compound of the present invention include compounds represented by any of the following structural formulas.

The benzene rings in the above structural formulas are each independently aryl having 6 to 16 carbon atoms, heteroaryl having 2 to 20 carbon atoms, diarylamino (where aryl is aryl having 6 to 10 carbon atoms), diarylboryl (wherein aryl is aryl having 6 to 10 carbon atoms), Aryl is an aryl having 6 to 10 carbon atoms, and two aryl may be linked by a single bond or a linking group), alkyl having 1 to 12 carbon atoms, or cycloalkyl having 3 to 16 carbon atoms. may be substituted with at least one substituent selected from the group consisting of alkyl having 1 to 5 carbon atoms and cycloalkyl having 5 to 10 carbon atoms,
At least one hydrogen in the compound represented by the above structural formula may be replaced with deuterium, cyano, or halogen.

More specific examples of polycyclic aromatic compounds include compounds represented by the following structural formulas.

2. Method for Producing a Polycyclic Aromatic Compound The polycyclic aromatic compound of the present invention is basically prepared by first combining rings A, B and C with a linking group (a group containing X, Y, Z or L). to produce an intermediate (first reaction), followed by a cyclization reaction to produce the final product (second reaction).

In the first reaction, for example, general reactions such as nucleophilic substitution reaction and Ullmann reaction can be used for the etherification reaction, and general reactions such as the Buchwald-Hartwig reaction can be used for the amination reaction. Moreover, in the second reaction, a Cadogan cyclization reaction, a tandem hetero Friedel-Crafts reaction, or the like can be used.

The second reaction includes four cyclization reactions shown in schemes (1) to (4) below. However, in the following schemes (1) to (4), substituents such as leaving groups attached to the A ring, B ring, C ring, L, X, Y and Z that are used in the cyclization reaction are omitted. ing.

Hereinafter, for the above case, compounds (a), (b), (c), (d), (e), (f), (g), in which the A ring, B ring and C ring are benzene rings, The preparation method for the cyclization reaction will be described using (h), (i) and compound (j) as examples.

Examples of Case 1 are the methods described in Scheme (5), Scheme (6) and Scheme (7).

In scheme (5), a nitrophenyl-bearing intermediate is reductively cyclized using PPh ₃ or P(OEt) ₃ , followed by Cadogan cyclization to synthesize an intermediate having a seven-membered ring. can be done. Then, using a copper catalyst, a palladium catalyst, or the like, the resulting intermediate having a 7-membered ring is subjected to a cross-coupling reaction with a halogenated aryl compound to obtain the desired product.

In scheme (6), a target product can be obtained by intramolecular cross-coupling reaction using a copper catalyst, a palladium catalyst, or the like.

In schemes (5) and (6) above, when a copper catalyst is used, copper powder, copper oxide, copper halide, or the like is used. The base used is cesium carbonate, potassium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium hydrogen carbonate, tripotassium phosphate, sodium hydride, etc., and the reaction accelerator is crown ether (e.g., 18-crown-6 -ether), polyethylene glycol (PEG), polyethylene glycol dialkyl ether (PEGDM), and the like. As a reaction solvent, N,N-dimethylformamide, nitrobenzene, dimethylsulfoxide, dichlorobenzene, o-dichlorobenzene, quinoline and the like are used. The reaction temperature is 160 to 250° C., but if the reactivity of the substrate is low, the reaction may be carried out at a higher temperature using an autoclave or the like.

When using a palladium catalyst, palladium acetate, palladium chloride, palladium bromide, tris(dibenzylideneacetone)dipalladium (0), tris(dibenzylideneacetone)dipalladium chloroform complex (0), tetrakis(triphenylphosphine) Palladium(0), [1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloritodichloromethane complex (1:1), and the like are used. The bases used are lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, sodium hydrogen carbonate, sodium hydride, potassium alkoxy (e.g. potassium methoxy, potassium ethoxy, potassium normal propoxy, potassium isopropoxy, n-butoxy potassium and tert-butoxypotassium) and alkoxysodium (eg, methoxysodium, ethoxysodium, normal propoxysodium, isopropoxysodium, n-butoxysodium and tert-butoxysodium). Reaction accelerators include 2,2'-(diphenylphosphino)-1,1'-binaphthyl, 1,1'-(diphenylphosphino)ferrocene, dicyclohexylphosphinobiphenyl, di-tert-butylphosphinobiphenyl, tri( tert-butyl)phosphine, 1-(N,N-dimethylaminomethyl)-2-(di-tert-butylphosphino)ferrocene, 1-(N,N-dibutylaminomethyl)-2-(di-tert- butylphosphino)ferrocene, 1-(methoxymethyl)-2-(di-tert-butylphosphino)ferrocene, 1,1′-bis(di-tert-butylphosphino)ferrocene, 2,2′-bis( Di-tert-butylphosphino)-1,1'-binaphthyl, 2-methoxy-2'-(di-tert-butylphosphino)-1,1'-binaphthyl and the like are used. Aromatic hydrocarbon solvents such as benzene, toluene, xylene and mesitylene are used as reaction solvents. A single solvent may be used, or a mixed solvent may be used. The reaction temperature is generally 50 to 200°C, preferably 80 to 140°C.

In scheme (7), the desired product can be obtained by intramolecular coupling reaction using a base in the absence of a catalyst or in the presence of a copper catalyst. When using a copper catalyst, copper powder, copper oxide, copper halide, or the like is used. Bases used include cesium carbonate, potassium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium hydrogen carbonate, tripotassium phosphate, sodium hydride and the like. As a reaction solvent, N,N-dimethylformamide, nitrobenzene, dimethylsulfoxide, N-methyl-2-pyrrolidone, dichlorobenzene, o-dichlorobenzene, quinoline and the like are used. The reaction temperature is 160 to 250° C., but if the reactivity of the substrate is low, the reaction may be carried out at a higher temperature using an autoclave or the like.

Examples of Case 2 are the methods described in Scheme (8), Scheme (9), Scheme (10) and Scheme (11).

In schemes (8) and (9) above, when a catalyst is used, a sulfonic acid derivative, a diazabicyclo derivative, a solid acid having a sulfonic acid group, or the like is used.

Examples of sulfonic acid derivatives include sulfonic acid, methanesulfonic acid, ethanesulfonic acid, trifluoromethanesulfonic acid, and p-toluenesulfonic acid.

Examples of diazabicyclo derivatives include diazabicycloundecene (DBU), diazabicyclononene (DBN), 1,4-diazabicyclo[2.2.2]octane (DABCO) and the like.

Specific solid acids having sulfonic acid groups include polystyrene-based sulfonic acid ion exchange resins manufactured by Sigma-Aldrich Japan LLC, such as AMBERLYST 15 (H), AMBERLYST 16 (H), AMBERLYST 36 (H), and AMBERLITE IR120. (H), AMBERJET 1200 (H), DOWEX 15W × 2, DOWEX 15W × 4, DOWEX 15W × 8, etc. Silica gel-based sulfonic acid fixed acid catalyst manufactured by Teika Co., Ltd., such as Teikacure-6, Teikacure-10, Teikacure -15 and the like.

Toluene, xylene, o-xylene, p-xylene, m-xylene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene and the like are used as the reaction solvent. . A single solvent may be used, or a mixed solvent may be used. The reaction temperature is usually in the range of 100-200°C. Since this reaction is a dehydration reaction, it is desirable to use an apparatus equipped with a Dean-Stark trap.

In schemes (10) and (11) above, examples of the base include N,N-diisopropylethylamine, triethylamine, 2,2,6,6-tetramethylpiperidine, 1,2,2,6,6- pentamethylpiperidine, N,N-dimethylaniline, N,N-dimethyltoluidine, 2,6-lutidine and the like.

Reaction solvents include o-dichlorobenzene, chlorobenzene, xylene, o-xylene, p-xylene, m-xylene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethyl Benzene etc. are used. A single solvent may be used, or a mixed solvent may be used. The reaction temperature is usually in the range of 120-220°C.

In schemes (12) and (13) above, examples of bases include pyridine, N,N-diisopropylethylamine, triethylamine, 2,2,6,6-tetramethylpiperidine, 1,2,2,6, 6-pentamethylpiperidine, N,N-dimethylaniline, N,N-dimethyltoluidine, 2,6-lutidine and the like.

Examples of reaction solvents include toluene, xylene, o-xylene, p-xylene, m-xylene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene. be done. A single solvent may be used, or a mixed solvent may be used. The reaction temperature is usually in the range of 0 to 180°C.

Examples of Case 3 are the methods described in Scheme (14) and Scheme (15).

In schemes (14) and (15) above, when a copper catalyst is used, copper powder, copper oxide, copper halide, or the like is used. The base used is cesium carbonate, potassium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium hydrogen carbonate, tripotassium phosphate, sodium hydride, etc., and the reaction accelerator is crown ether (e.g., 18-crown-6 -ether), polyethylene glycol (PEG), polyethylene glycol dialkyl ether (PEGDM), and the like. As a reaction solvent, N,N-dimethylformamide, nitrobenzene, dimethylsulfoxide, N-methyl-2-pyrrolidone, dichlorobenzene, o-dichlorobenzene, quinoline and the like are used. The reaction temperature is 160 to 250° C., but if the reactivity of the substrate is low, the reaction may be carried out at a higher temperature using an autoclave or the like.

When using a palladium catalyst, palladium acetate, palladium chloride, palladium bromide, tris(dibenzylideneacetone)dipalladium (0), tris(dibenzylideneacetone)dipalladium chloroform complex (0), tetrakis(triphenylphosphine) Palladium(0), [1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloritodichloromethane complex (1:1), and the like are used. The bases used are lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, sodium hydrogen carbonate, sodium hydride, potassium alkoxy (e.g. potassium methoxy, potassium ethoxy, potassium normal propoxy, potassium isopropoxy, n-butoxy potassium and tert-butoxypotassium) and alkoxysodium (eg, methoxysodium, ethoxysodium, normal propoxysodium, isopropoxysodium, n-butoxysodium and tert-butoxysodium). Reaction accelerators include 2,2'-(diphenylphosphino)-1,1'-binaphthyl, 1,1'-(diphenylphosphino)ferrocene, dicyclohexylphosphinobiphenyl, di-tert-butylphosphinobiphenyl, tri( tert-butyl)phosphine, 1-(N,N-dimethylaminomethyl)-2-(di-tert-butylphosphino)ferrocene, 1-(N,N-dibutylaminomethyl)-2-(di-tert- butylphosphino)ferrocene, 1-(methoxymethyl)-2-(di-tert-butylphosphino)ferrocene, 1,1′-bis(di-tert-butylphosphino)ferrocene, 2,2′-bis( Di-tert-butylphosphino)-1,1'-binaphthyl, 2-methoxy-2'-(di-tert-butylphosphino)-1,1'-binaphthyl and the like are used. Aromatic hydrocarbon solvents such as benzene, toluene, xylene and mesitylene are used as reaction solvents. A single solvent may be used, or a mixed solvent may be used. The reaction temperature is generally 50 to 200°C, preferably 80 to 140°C.

An example of case 4 is the method described in scheme (16) and scheme (17).

In scheme (16), after deprotonation with a deprotonating agent such as n-butyllithium, sec-butyllithium or t-butyllithium, boron trichloride or boron tribromide is added to effect lithium-boron metal exchange. After performing, a Lewis acid such as AlCl ₃ and a Bronsted base such as 2,2,6,6-tetramethylpiperidine (TMP) are added to cause a Friedel-Crafts type reaction to obtain the desired product. .

In scheme (17), after deprotonation with a deprotonating agent such as n-butyllithium, sec-butyllithium or t-butyllithium, a phosphorus introducing agent, sulfur are added in that order, and finally a Lewis acid such as AlCl ₃ is added. and by adding a Bronsted base such as N,N-diisopropylethylamine, a Friedel-Crafts type reaction can be performed to obtain a compound that is a phosphorus sulfide. Further, a phosphorus oxide compound can be obtained by treating the obtained phosphorus sulfide compound with m-chloroperbenzoic acid (m-CPBA). Furthermore, a compound that is a cyclic phosphine can be obtained by treating this phosphorus oxide compound with triethylphosphine (PEt ₃ ).

In schemes (16) and (17), the deprotonating agent includes, in addition to n-BuLi, alkyllithiums such as MeLi, s-BuLi, t-BuLi and PhLi, MeMgBr, EtMgBr and n-BuMgBr. or alkali metal hydrides such as NaH and KH.

Lewis acids include _AlCl3 , _AlBr3 , _BF3.OEt2 , _BCl3 , _BBr3 , _GaCl3 , _GaBr3 , _InCl3 , _{InBr3 ,} In(OTf) ₃ , _SnCl4 , _SnBr4 , AgOTf, Sc (OTf) ₃ , ZnCl ₂ , ZnBr ₂ , Zn(OTf) ₂ , MgCl ₂ , MgBr ₂ , Mg(OTf) ₂ and the like are used.

Bronsted bases include N,N-diisopropylethylamine, 2,2,6,6-tetramethylpiperidine, 1,2,2,6,6-pentamethylpiperidine, 2,4,6-collidine, 2,6 -Lutidine, triethylamine, triisobutylamine, etc. are used.

Solvents include anhydrous ether solvents such as anhydrous diethyl ether, anhydrous THF and anhydrous dibutyl ether; aromatic hydrocarbon solvents such as benzene, toluene, xylene and mesitylene; aromatic solvents such as chlorobenzene and 1,2-dichlorobenzene. group halide-based solvents are used.

In scheme (17), phosphorus introduction agents include halides such as PF ₃ , PCl ₃ , PBr ₃ and PI ₃ , P(OMe) ₃ , P(OEt) ₃ , P(O-nPr) ₃ , P( Alkoxy derivatives such as O-iPr) ₃ , P(O-nBu) ₃ , P(O-iBu) ₃ , P(O-secBu) ₃ , P(Ot-Bu) ₃ , P(OPh) ₃ , Aryloxy derivatives such as P(O-naphthyl) ₃ , P(OAc) ₃ , P(O-trifluoroacetyl) ₃ , P(O-propionyl) ₃ , P(O-butyryl) ₃ , P(O-benzoyl ) ₃ , PCl( _NMe2 ) ₂ , PCl(NEt2) ₂ , PCl _{( NPr2} ) ₂ , PCl( _NBu2 ) ₂ , PBr( _NMe2 ) ₂ , PBr( _NEt2 ) ₂ , PBr Haloamino derivatives such as (NPr ₂ ) ₂ and PBr(NBu ₂ ) ₂ can be mentioned.

Schemes (5) to (17) above are methods for producing representative compounds of the polycyclic aromatic compounds of the present invention, and other compounds can be synthesized by similar methods. The polycyclic aromatic compounds of the present invention also include compounds in which at least a portion of the hydrogens are replaced with deuterium, cyano, or halogen, such compounds being deuterated at desired positions. , cyanated, fluorinated or chlorinated starting materials can be used in analogy to the above.

3. Organic Device The polycyclic aromatic compound according to the present invention can be used as a material for organic devices. Organic devices include, for example, organic electroluminescence devices, organic field effect transistors, organic thin film solar cells, and the like.

3-1. Organic Electroluminescence Device Hereinafter, the organic EL device according to the present embodiment will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an organic EL element according to this embodiment.

<Structure of Organic Electroluminescent Device>
The organic EL device 100 shown in FIG. 1 includes a substrate 101, an anode 102 provided on the substrate 101, a hole injection layer 103 provided on the anode 102, and a The hole-transport layer 104 provided, the light-emitting layer 105 provided over the hole-transport layer 104, the electron-transport layer 106 provided over the light-emitting layer 105, and the electron-transport layer 106 provided and a cathode 108 provided on the electron injection layer 107 .

Note that the organic EL element 100 is fabricated in reverse order, for example, the substrate 101, the cathode 108 provided on the substrate 101, the electron injection layer 107 provided on the cathode 108, and the electron injection layer 107 an electron transport layer 106 provided on the electron transport layer 106; a light emitting layer 105 provided on the electron transport layer 106; a hole transport layer 104 provided on the light emitting layer 105; A structure having a hole-injection layer 103 provided at the bottom and an anode 102 provided on the hole-injection layer 103 may be employed.

All of the above layers are not indispensable, and the minimum structural unit is composed of 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 is an optional layer. Moreover, each of the above layers may be composed of a single layer, or may be composed of a plurality of layers.

In addition to the configuration of the above-described "substrate/anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode", the layers constituting the organic EL element may include " substrate/anode/hole-transporting layer/luminescent layer/electron-transporting layer/electron-injecting layer/cathode”, “substrate/anode/hole-injecting layer/luminescent layer/electron-transporting layer/electron-injecting layer/cathode”, “substrate/ Anode/Hole Injection Layer/Hole Transport Layer/Light Emitting Layer/Electron Injection Layer/Cathode", "Substrate/Anode/Hole Injection Layer/Hole Transport Layer/Light Emitting Layer/Electron Transport Layer/Cathode", "Substrate/ Anode/light emitting layer/electron transport layer/electron injection layer/cathode", "substrate/anode/hole transport layer/light emitting 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 /Emitting layer/Electron transporting layer/Cathode" or "Substrate/Anode/Emitting layer/Electron injection layer/Cathode".

The organic EL device may further have either or both of an electron blocking layer (electron blocking layer) and a hole blocking layer (hole blocking layer). The electron-blocking layer has a LUMO shallower than the light-emitting layer and a HOMO close to the light-emitting layer or the hole-transporting layer, and is positioned between the light-emitting layer and the hole-transporting layer. Since the electrons remain in the light-emitting layer and do not leak to the hole transport layer, it is possible to prevent a decrease in efficiency due to a decrease in recombination efficiency and a shortened lifetime due to deterioration of the hole transport layer. The hole-blocking layer has a HOMO deeper than the light-emitting layer and a LUMO close to the light-emitting layer or hole-transporting layer and is positioned between the light-emitting layer and the electron-transporting layer. Since the holes remain in the light-emitting layer and do not leak out to the electron transport layer, it is possible to prevent shortening of life due to deterioration of the electron transport layer and decrease in efficiency due to decrease in recombination efficiency. The hole injection/transport layer may also serve as the electron blocking layer. The electron injection/transport layer may also serve as the hole blocking layer.

The organic EL device may also have a high T1 layer. A high T1 layer has a higher T1 than the host compound, assisting dopant compound or emitting dopant compound used in the emissive layer and is between the emissive layer and the hole transport layer and/or between the emissive layer and the electron blocking layer. placed. Although the value of T1 energy differs depending on the emission mechanism of the device, it has a higher T1 than the compound used as the host. Having a high T1 layer around the light-emitting layer confines the triplet energy and converts the triplet energy, which normally does not lead to light emission with fluorescent molecules, into singlet energy, resulting in high efficiency. A hole injection/transport layer or an electron blocking layer may also serve as the high T1 layer. The electron injection/transport layer or the hole blocking layer may also serve as the high T1 layer.

The polycyclic aromatic compound of the present invention is preferably used as a material for organic electroluminescence devices. In general, a compound having a donor structure can be used for the hole-transporting host material and the hole-transporting layer in the light-emitting layer, and a compound having an acceptor structure can be used for the electron-transporting layered host material and the electron-transporting layer. A compound having both a donor structure and an acceptor structure can be used for both the hole-transporting layer, the host in the light-emitting layer, and the electron-transporting layer. Donor structures and acceptor structures can be referred to, for example, Advanced Functional Materials 2020, 2008332 and the like. More specifically, the donor structure includes triarylamine structure and carbazole structure, and the acceptor structure includes triazine structure, pyrimidine structure and pyridine structure. The polycyclic aromatic compound according to the present invention can be used as a host material, hole-transporting layer material, electron-transporting layer material, etc. in the light-emitting layer, depending on the partial structure it has.

<Substrate in Organic Electroluminescent Device>
A substrate 101 is a support for the organic EL element 100, and is usually made of quartz, glass, metal, plastic, or the like. The substrate 101 is formed in a plate shape, a film shape, or a sheet shape depending on the purpose, and for example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, or the like is used. Of these, glass plates and transparent synthetic resin plates such as polyester, polymethacrylate, polycarbonate and polysulfone are preferred. If it is a glass substrate, soda-lime glass, alkali-free glass, or the like is used, and the thickness should be sufficient to maintain mechanical strength. In addition, the substrate 101 may be provided with a gas barrier film such as a dense silicon oxide film on at least one side thereof in order to enhance gas barrier properties. When used, it is preferable to provide a gas barrier film.

<Anode in Organic Electroluminescent Device>
Anode 102 serves to inject holes into 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 these layers. It will be.

Materials for forming the anode 102 include inorganic compounds and organic compounds. Examples of inorganic compounds include metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (ITO), indium-zinc oxide metal (IZO), etc.), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass, Nesa glass, and the like. Examples of organic compounds include polythiophenes such as poly(3-methylthiophene), and conductive polymers such as polypyrrole and polyaniline. In addition, it can be used by appropriately selecting from materials used as anodes of organic EL elements.

<Hole Injection Layer and Hole Transport Layer in Organic Electroluminescent Device>
The hole-injecting layer 103 plays a role of efficiently injecting holes moving from the anode 102 into the light-emitting layer 105 or the hole-transporting layer 104 . The hole transport layer 104 plays a role of efficiently transporting 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 each formed by stacking or mixing one or more kinds of hole injection/transport materials. Also, an inorganic salt such as iron (III) chloride may be added to the hole injection/transport material to form the layer.

As a hole-injecting/transporting substance, it is necessary to efficiently inject and transport holes from the positive electrode between electrodes to which an electric field is applied. It is desirable to For this purpose, it is preferable that the ionization potential is low, the hole mobility is high, the stability is excellent, and impurities that become traps are less likely to occur during manufacture and use. It is also preferable to use the polycyclic aromatic compound of the present invention as a material for the hole transport layer.

Materials for forming the hole injection layer 103 and the hole transport layer 104 include compounds conventionally used as charge transport materials for holes in photoconductive materials, p-type semiconductors, and hole injection layers of organic EL devices. Any compound can be selected and used from known compounds used for the hole transport layer. Specific examples thereof include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis(N-arylcarbazole) or bis(N-alkylcarbazole), triarylamine derivatives (aromatic tertiary Polymers with amino in the main or side chain, 1,1-bis(4-di-p-tolylaminophenyl)cyclohexane, N,N'-diphenyl-N,N'-di(3-methylphenyl)-4 ,4'-diaminobiphenyl, N,N'-diphenyl-N,N'-dinaphthyl-4,4'-diaminobiphenyl, N,N'-diphenyl-N,N'-di(3-methylphenyl)-4 ,4′-diphenyl-1,1′-diamine, N,N′-dinaphthyl-N,N′-diphenyl-4,4′-diphenyl-1,1′-diamine, N ⁴ ,N ⁴ ′ -diphenyl- N ⁴ ,N ^4′ -bis(9-phenyl-9H-carbazol-3-yl)-[1,1′-biphenyl]-4,4′-diamine, N ⁴ ,N ⁴ ,N ^4′ ,N ^{4 '} -tetra[1,1'-biphenyl]-4-yl)-[1,1'-biphenyl]-4,4'-diamine, 4,4',4"-tris(3-methylphenyl(phenyl) triphenylamine derivatives such as amino)triphenylamine, starburst amine derivatives, etc.), stilbene derivatives, phthalocyanine derivatives (metal-free, copper phthalocyanine, etc.), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives, thiophene derivatives, oxadiazole derivatives , quinoxaline derivatives (e.g., 1,4,5,8,9,12-hexaazatriphenylene-2,3,6,7,10,11-hexacarbonitrile, etc.), heterocyclic compounds such as porphyrin derivatives, polysilanes, etc. Polycarbonate, styrene derivatives, polyvinylcarbazole, polysilane and the like having the above-mentioned monomers in the side chains are preferable for polymer systems, but a thin film necessary for manufacturing a light-emitting device can be formed and holes can be injected from the anode. Further, the compound is not particularly limited as long as it is a compound capable of transporting holes.

It is also known that the conductivity of organic semiconductors is strongly influenced by their doping. Such an organic semiconductor matrix material is composed of a compound with good electron-donating property or a compound with good electron-accepting property. Strong electron acceptors such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinonedimethane (F4TCNQ) are known for doping electron donors. (For example, M. Pfeiffer, A. Beyer, T. Fritz, K. Leo, Appl. Phys. Lett., 73(22), 3202-3204 (1998)” and the literature “J. Pfeiffer, T. Fritz, K. Leo, Appl. Phys. Lett., 73(6), 729-731 (1998)"). They generate so-called holes by an electron transfer process in an electron donating base material (hole transport material). The conductivity of the base material varies considerably depending on the number and mobility of holes. As matrix materials with hole-transport properties, for example, benzidine derivatives (such as TPD) or starburst amine derivatives (such as TDATA), or certain metal phthalocyanines (especially zinc phthalocyanine (ZnPc), etc.) are known ( Japanese Patent Application Laid-Open No. 2005-167175).

The hole injection layer material and the hole transport layer material described above are polymer compounds obtained by polymerizing a reactive compound having a reactive substituent substituted thereon as a monomer, or a polymer crosslinked product thereof, or A pendant-type polymer compound obtained by reacting a main chain-type polymer with the reactive compound or a pendant-type polymer crosslinked product thereof can also be used as a hole layer material.

<Light Emitting Layer in Organic Electroluminescent Device>
The light-emitting layer 105 is a layer that emits light by recombining holes injected from the anode 102 and electrons injected from the cathode 108 between electrodes to which an electric field is applied. As a material for forming the light-emitting layer 105, any compound (light-emitting compound) that emits light when excited by recombination of holes and electrons can be used. It is preferably a compound that exhibits a strong luminescence (fluorescence) efficiency at . It is also preferable to use the polycyclic aromatic compound of the present invention as a material for a light-emitting layer.

The light-emitting layer may be a single layer or a plurality of layers, each of which is formed of a light-emitting layer material (host material, dopant material). The host material and the dopant material may be of one kind, or may be a combination of a plurality of them. The dopant material may be included entirely or partially in the host material. As a doping method, it can be formed by a co-evaporation method with the host material. It may be filmed.

The amount of host material to be used varies depending on the type of host material, and may be determined according to the properties of the host material. A guideline for the amount of the host material used is preferably 50 to 99.999% by mass, more preferably 80 to 99.95% by mass, and still more preferably 90 to 99.9% by mass with respect to the total mass of the material for the light-emitting layer. % by mass.

The amount of dopant material used varies depending on the type of dopant material, and may be determined according to the properties of the dopant material. A guideline for the amount of the dopant material used is preferably 0.001 to 50% by mass, more preferably 0.05 to 20% by mass, and still more preferably 0.1 to 10% by mass with respect to the total mass of the material for the light-emitting layer. % by mass. The above range is preferable in that, for example, the phenomenon of concentration quenching can be prevented. From the viewpoint of durability, it is also preferable that some or all of the hydrogen atoms in the dopant material are deuterated.

As the dopant material, an emitting dopant and an assisting dopant material may be used. A thermally activated delayed fluorescence material is preferably used as the assisting dopant material. In an organic electroluminescence device using an assisting dopant material, it is preferable to use a low concentration of the emitting dopant material in order to prevent the concentration quenching phenomenon. A higher concentration of the assisting dopant material is preferable from the viewpoint of the efficiency of the thermally activated delayed fluorescence mechanism. Furthermore, in an organic electroluminescence device using a thermally activated delayed fluorescence assisting dopant material, the efficiency of the thermally activated delayed fluorescence mechanism of the assisting dopant material is lower than the amount of the assisting dopant material used. It is preferred that the amount of emitting dopant material used is low.

When the assisting dopant material is used, the amounts of the host material, the assisting dopant material and the emitting dopant material are 40 to 99% by mass and 59 to 1% by mass, respectively, based on the total mass of the material for the light-emitting layer. % and 20 to 0.001% by mass, preferably 60 to 95% by mass, 39 to 5% by mass and 10 to 0.01% by mass, more preferably 70 to 90% by mass, and 29 to 10% by mass, respectively. % by weight and 5 to 0.05% by weight.

<Host material>
Host materials include condensed ring derivatives such as anthracene and pyrene, bisstyryl anthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, fluorene derivatives, benzo Examples include fluorene derivatives, N-phenylcarbazole derivatives, carbazonitrile derivatives and the like.

The triplet energy of the host material is higher than the triplet energy of the dopant having the highest triplet energy in the light-emitting layer or the assisting dopant, from the viewpoint of promoting the generation of TADF in the light-emitting layer without inhibiting it. Specifically, the triplet energy of the host material is preferably 0.01 eV or higher, more preferably 0.03 eV or higher, and still more preferably 0.1 eV or higher. A TADF-active compound may also be used as the host material.

The host material may be of one type or a combination of multiple types. In the case of a combination of a plurality of materials, it is preferably a combination of a hole-transporting host material and an electron-transporting host material.

The polycyclic aromatic compound of the present invention can be preferably used as a host material. The polycyclic aromatic compound of the present invention may be used alone, as a hole-transporting host material, or as an electron-transporting host material.

[Hole-transporting host material (HH)]
Examples of preferred hole-transporting host materials (HH) include the polycyclic aromatic compound of the present invention, the compound represented by formula (HH-1), and the partial structure represented by formula (HH-1). can be mentioned.

In formula (HH-1),
Q is >O, >S, or >NA;
one carbon atom next to the carbon atom to which Q is bonded in each of the two phenyls in formula (HH-1) may be bonded to each other with L;
L is a single bond, >O, >S or >C(-A) ₂ ;
A is a hydrogen atom, aryl, heteroaryl, _diarylamino , alkyl, cycloalkyl, alkoxy or aryloxy; may be formed.

When the hole-transporting host material contains a structure represented by formula (HH-1) as a partial structure, it may contain one partial structure 1, but preferably contains two or more. When two or more are included, the two or more partial structures may be the same or different. Two or more partial structures may be bonded to each other with a single bond, or may be bonded so as to share any rings contained in the partial structures, and any rings contained in the partial structures may be fused to each other. may be combined in such a way that The substructure may further have substituents selected from aryl, heteroaryl, diarylamino, or aryloxy.

The hole-transporting host material is a compound containing one or more partial structures selected from the group consisting of a condensed polycyclic ring including a triarylamine structure, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, and phenoxazine or phenothiazine. is preferably The hole-transporting host material may contain one such partial structure 1, but preferably contains two or more. When two or more are included, the two or more partial structures may be the same or different.

Specific examples of hole-transporting host materials include the following compounds.

Of the above, HH-1-1, HH-1-2, HH-1-4 to HH-1-12, HH-1-17, HH-1-18, HH-1-20 to HH-1- 24, HH-1-82, HH-1-84 to HH-1-89, HH-1-91, HH-1-92 and HH-1-106 to HH-1-108 are preferred.

[Electron transporting host material (EH)]
Examples of the electron-transporting host material (EH) include the polycyclic aromatic compound of the present invention, the compound represented by formula (EH-1), and the partial structure represented by formula (EH-1). compounds having

In formula (EH-1),
each J is independently =C(-A)- or =N-, and at least three Js are =C(-A)-;
Z is -O-, -S-, -C(=O)-, -P(=O)(-A)-, -P(=S)(-A)-, -N(-A)- , -B(-A)- or -S(=O) ₂ -,
J next to the carbon atom to which Z is bonded and A to which Z is bonded may be bonded to each other with L,
L is a single bond, >O, >S or >C(-A) ₂ ;
A is hydrogen, aryl, heteroaryl, diarylamino _, alkyl, cycloalkyl, triarylsilyl, alkoxy or aryloxy; , may form a cycloalkyl,
When all J are =C(-A)-, either one of A or Z has a heteroatom.

For aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, triarylsilyl, alkoxy or aryloxy represented by A in formula (EH-1), refer to the description of A in formula (HH-1). can. For aryl, heteroaryl, and cycloalkyl when two A's in formula (EH-1) are bonded together to form aryl, heteroaryl, and cycloalkyl, refer to the description in formula (HH-1). can.

When the electron-transporting host material contains the structure represented by Formula (EH-1) as a partial structure, it may contain one partial structure, but preferably contains two or more partial structures. When two or more are included, the two or more partial structures may be the same or different. Two or more partial structures may be bonded to each other with a single bond, or may be bonded so as to share any rings contained in the partial structures, and any rings contained in the partial structures may be fused to each other. may be combined in such a way that The substructure may further have substituents selected from aryl, heteroaryl, diarylamino, or aryloxy.

Specific examples of electron-transporting host materials include the following compounds.

Another preferred example of the electron-transporting host material (compound having a partial structure represented by formula (EH-1)) is a polycyclic aromatic compound represented by the following formula (EH-1b), or the following formula ( Multimers of polycyclic aromatic compounds having a plurality of structures represented by EH-1b) can be mentioned.

In formula (EH-1b),
R ¹ , R ² , R ³ , R ⁴ and R ⁵ (hereinafter also referred to as “R ¹ etc.”) are each independently hydrogen or a substituent selected from Substituent Group Z;
In formula (EH-1b), X ¹ and X ² are each independently >NR (amine nitrogen), >O, >C(-R) ₂ , >S or >Se; ¹ and X ² cannot both be >C(-R) ₂ ,
Each R in >N--R and >C(--R) ₂ is independently hydrogen or a substituent selected from substituent group Z, and furthermore, aryl, heteroaryl, alkyl or cycloalkyl ( , a second substituent), and the Rs of the above-mentioned >NR and >C(-R) ₂ are each independently connected to the above-mentioned a-ring, b-ring and c-ring by a linking group or a single bond. It may be attached to at least one ring.
Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ (hereinafter also referred to as “Y ¹ etc.”) are each independently =C(-R)- or =N- (pyridinic nitrogen ) and at least one is =N- (pyridinic nitrogen);
Each R in the =C(-R)- is independently hydrogen or a substituent selected from the group Z of substituents.
Adjacent groups among R ¹ , R ² , R ³ , R ⁴ and R ⁵ , and R of ═C(—R)— as Y ¹ to Y ⁶ are bonded to form a ring, b An aryl ring or a heteroaryl ring may be formed together with the ring and at least one ring of the c ring, and the formed ring may be substituted with at least one group selected from the substituent group Z.
At least one hydrogen in the compounds and structures represented by formula (EH-1b) may be replaced with cyano, halogen or deuterium.

In formula (EH-1b), R ¹ , R ² , R ³ , R ⁴ and R ⁵ are all hydrogen, or both R ³ and R ⁴ are hydrogen and R ¹ , R ² and R ⁵ are substituents other than hydrogen, and the others are preferably hydrogen. Preferred substituents are alkyl, aryl optionally substituted with alkyl or heteroaryl, heteroaryl optionally substituted with alkyl or aryl, or diarylamino optionally substituted with alkyl or aryl. At this time, alkyl is preferably alkyl having 1 to 6 carbon atoms (methyl, t-butyl, etc.), aryl is preferably phenyl or biphenyl, and heteroaryl is triazinyl, carbazolyl (2-carbazolyl, 3-carbazolyl , 9-carbazolyl, etc.), pyrimidinyl, pyridinyl, dibenzofuranyl or dibenzothienyl are preferred. Specific examples include phenyl, biphenyl, diphenyltriazinyl, carbazolyltriazinyl, monophenylpyrimidinyl, diphenylpyrimidinyl, carbazolyltriazinyl, pyridinyl, dibenzofuranyl and dibenzothienyl.

Y ¹ etc. are each independently =C(-R)- or =N- and at least one is =N-. Any of Y ¹ to Y ⁶ may be =N-. Preferably, Y ¹ and Y ⁶ are =N- (a ring is a pyrimidine ring), Y ¹ or Y ⁶ is =N- (a ring is a pyridine ring), Y ² and Y ⁵ are =N- (b ring and ring c is a pyridine ring), Y ³ and Y ⁴ are =N- (rings b and c are pyridine rings), Y ² to Y ⁵ are =N- (rings b and c are pyrimidine rings), Y ¹ , Y ³ , Y ⁴ and Y ⁶ are =N- (ring a is a pyrimidine ring, rings b and c are pyridine rings), Y ¹ , Y ² , Y ⁵ and Y ⁶ are =N- (ring a is a pyrimidine ring , rings b and c are pyridine rings), Y ¹ to Y ⁶ are =N- (rings a, b and c are pyrimidine rings), Y ² or Y ⁵ is =N- (rings b and c are pyridine ring).

In addition to the above =N- configuration relationship, X ¹ and X ² are preferably >O, and a polycyclic aromatic compound containing a partial structure represented by any of the following formulas is preferred.

In particular, the polycyclic aromatic compound containing the partial structure represented by formula (EH-1b-N1) has a higher E _S1 , a higher E _T1 and a smaller ΔE _S1T1 than the structure without N.
Specific examples of the polycyclic aromatic compound represented by formula (EH-1b) are shown below.

Among the above, EH-1-1 to EH-1-4, EH-1-10, EH-1-21 to EH-1-25, EH-1-32, EH-1-33, EH-1- 51 to EH-1-59, EH-1-61, EH-1-66, EH-1-68, EH-1-71, EH-1-72, EH-1-90, EH-1-100, EH-1-101, EH-1-104, EH-1-115, EH-1-117, EH-1-120, EH-1-122, EH-1-123, EH-1-127 to EH- 1-130 is preferred.

[Combination of hole-transporting host material and electron-transporting host material]
The combination of hole-transporting host material and electron-transporting host material is selected according to the HOMO, LUMO and excited triplet energies of the hole-transporting host material, the electron-transporting host material and the dopant material.
Regarding HOMO and LUMO, the HOMO (HH) of the hole-transporting host material is shallower than the HOMO (EH) of the electron-transporting host material, and the LUMO (EH) of the electron-transporting host material is shallower than the LUMO of the hole-transporting host material. A combination deeper than (HH) is selected, more specifically, a combination in which HOMO (HH) is shallower than HOMO (EH) by 0.10 eV or more and LUMO (HH) is deeper than HOMO (EH) by 0.10 eV or more is preferable, A combination in which HOMO (HH) is 0.20 eV or more shallower than HOMO (EH) and LUMO (HH) is 0.20 eV or more deeper than HOMO (EH) is more preferable, and HOMO (HH) is 0.25 eV or more than HOMO (EH). A shallow combination in which LUMO (HH) is deeper than HOMO (EH) by 0.25 eV or more is more preferable.

The hole-transporting host material and the electron-transporting host material may be a combination that forms an aggregate called an exciplex. It is generally known that an exciplex is likely to form between a material with a relatively deep LUMO level and a material with a shallow HOMO level. Interaction between a hole-transporting host material and an electron-transporting host material, specifically whether or not an exciplex is formed, can be determined by using a single-layer film consisting of only a hole-transporting host material and an electron-transporting host material. Emission spectra (fluorescence and phosphorescence spectra) are measured by forming under the same conditions as those for forming the light-emitting layer, and the obtained emission spectra are the light emitted by the hole-transporting host material and the electron-transporting host material independently. It can be judged by comparing with the spectrum. The spectrum of the mixed film containing the hole-transporting host material and the electron-transporting host material exhibits an emission wavelength different from the spectrum of the film of the hole-transporting host material and the spectrum of the film of the electron-transporting host material. can be determined by Specifically, a difference of 10 nm or more in the peak wavelengths of the spectra may be used as an index.

Specific examples of combinations of hole-transporting host materials and electron-transporting host materials that do not form exciplexes include the following combinations. In order to satisfy the physical property values of HOMO, LUMO and excited triplet energy, the hole-transporting host material has partial structures of carbazole, dibenzofuran, dibenzothiophene, triarylamine, inderocarbazole and benzoxazinophenoxazine. is preferred, compounds having carbazole, dibenzofuran and dibenzothiophene as partial structures are more preferred, and compounds having carbazole as a partial structure are even more preferred. Similarly, in the electron-transporting host material, compounds having pyridine, triazine, phosphine oxide, benzofuropyridine and dibenzooxacillin as partial structures are preferred, and compounds having triazine, phosphine oxide, benzofuropyridine and dibenzooxacillin as partial structures. is more preferred, and triazine-bearing compounds are even more preferred.

More specifically, the hole-transporting host material is HH-1-1, HH-1-2, HH-1-4 to HH-1-12, HH-1-17, HH-1-18, HH-1-20 to HH-1-24, HH-1-82, HH-1-84 to HH-1-89, HH-1-91, HH-1-92 and HH-1-106 to HH- 1-108, and the electron-transporting host material is EH-1-1 to EH-1-4, EH-1-10, EH-1-21 to EH-1-25 , EH-1-32, EH-1-33, EH-1-51 to EH-1-59, EH-1-61, EH-1-71, EH-1-72, EH-1-90, EH -1-100, EH-1-101, EH-1-104, EH-1-117, EH-1-120, EH-1-122, EH-1-123, and EH-1-127 to EH- It is preferably selected from the group consisting of 1-130. Preferred examples of combinations include compound HH-1-1 and compound EH-1-22, compound HH-1-1 and compound EH-1-23, compound HH-1-1 and compound EH-1-24, compound HH-1-2 and compound EH-1-22, compound HH-1-2 and compound EH-1-23, compound HH-1-2 and compound EH-1-24, or compound HH-1-1 and compound and EH-1-128.

Specific examples of combinations of hole-transporting host materials and electron-transporting host materials that form an exciplex include the following combinations. Compounds having carbazole, triarylamine, inderocarbazole and benzoxazinophenoxazine as a partial structure are preferred as the hole-transporting host material in order to satisfy the physical property values of HOMO, LUMO and excited triplet energy. , triarylamine, inderocarbazole and benzoxazinophenoxazine as partial structures are more preferred, and compounds having triarylamine as a partial structure are even more preferred. Similarly, in the electron-transporting host material, compounds having pyridine, triazine, phosphine oxide and benzofuropyridine as partial structures are preferred, and compounds having triazine, phosphine oxide, benzofuropyridine and dibenzoxacillin as partial structures are more preferred. , phosphine oxides and triazines are more preferred.

More specifically, the hole-transporting host material is HH-1-1, HH-1-2, HH-1-11, HH-1-12, HH-1-17, HH-1-18, Preferably selected from the group consisting of HH-1-23 and HH-1-24, the electron-transporting host material is EH-1-1 to EH-1-4, EH-1-21 to EH-1 -25, EH-1-51 to EH-1-57, EH-1-59, EH-1-66, EH-1-68, EH-1-90, EH-1-100, EH-1-101 , EH-1-104, EH-1-117, EH-1-120, EH-1-122, EH-1-123, and EH-1-127 to EH-1-130 is preferred. Preferred examples of combinations include compound HH-1-1 and compound EH-1-21, compound HH-1-2 and compound EH-1-21, compound HH-1-12 and compound EH-1-117, compound HH-1-1 and compound EH-1-130, compound HH-1-33 and compound EH-1-117, compound HH-1-48 and compound EH-1-117 or compound HH-1-49 and compound EH -1-117 can be mentioned.

For other specific combinations of hole-transporting host materials and electron-transporting host materials, see Organic Electronics 66 (2019) 227-24, Advanced. Functional Materials 25 (2015) 361-366. , Advanced Materials 26 (2014) 4730-4734. , ACS Applied Materials and Interfaces 8 (2016) 32984-32991. 、ＡＣＳ Ａｐｐｌｉｅｄ Ｍａｔｅｒａｌｓ ａｎｄ Ｉｎｔｅｒｆａｃｅｓ ２０１６，８，９８０６－９８１０、ＡＣＳ Ａｐｐｌｉｅｄ Ｍａｔｅｒｉａｌｓ ａｎｄ Ｉｎｔｅｒｆａｃｅｓ ２０１６，８，３２９８４－３２９９１、Ｊｏｕｒｎａｌ ｏｆ Ｍａｔｅｒｉａｌｓ Ｃｈｅｍｉｓｔｙ Ｃ，２０１８，６，８７８４－８７９２、Ａｎｇｅｗａｎｔｅ Ｃｈｅｍｉｅ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｅｄｉｔｉｏｎ． 2018, 57, 12380-12384, Advanced Functional Materials, 24, 2014, 3970, Advanced Materials, 26, 2014, 5684, and Synthetic Metals, 201, 2015, 49.

<Dopant material>
Known compounds can be used as the dopant material, and can be selected from various materials depending on the desired emission color. Specifically, for example, phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopyrene, dibenzopyrene, rubrene and chrysene condensed ring derivatives, benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, benzotriazole derivatives, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, imidazole derivatives, thiadiazole derivatives, triazole derivatives, pyrazoline derivatives, stilbene derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives (JP-A-1-245087), bisstyrylarylene derivatives (JP-A-2-247278), diazaindacene derivatives, furan derivatives, benzofuran derivatives, phenylisobenzofuran, dimesitylisobenzofuran, di(2-methylphenyl) isobenzofuran derivatives such as isobenzofuran, di(2-trifluoromethylphenyl)isobenzofuran, phenylisobenzofuran, dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7-piperidinocoumarin derivatives, 7-hydroxycoumarin derivatives, 7- Coumarin derivatives such as methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolylcoumarin derivatives, 3-benzimidazolylcoumarin derivatives, 3-benzoxazolylcoumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, polymethine derivatives, cyanine derivatives, oxobenzoanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyrylium derivatives, carbostyryl derivatives, acridine derivatives, oxazine derivatives, phenylene oxide derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, furopyridine derivatives, 1 , 2,5-thiadiazolopyrene derivatives, pyrromethene derivatives, perinone derivatives, pyrrolopyrrole derivatives, squarylium derivatives, violanthrone derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives and benzofluorene derivatives.

In the light-emitting layer, it is preferable to use the polycyclic aromatic compound of the present invention as a host material and use a phosphorescent material or a TADF material (thermally activated delayed phosphor) as a dopant material.

[Phosphorescent material]
Phosphorescent materials utilize intramolecular spin-orbital interactions (heavy atom effect) by metal atoms to obtain emission from triplets. As such a phosphorescent material, for example, a luminescent metal complex can be used. Examples of the luminescent metal complex include compounds represented by the following formulas (B-1) and (B-2).

In formula (B-1), M is at least one selected from the group consisting of Ir, Pt, Au, Eu, Ru, Re, Ag and Cu; n is an integer of 1 to 3; XY" is each independently a bidentate ligand.
In formula (B-2), M is at least one selected from the group consisting of Pt, Re and Cu, and "WXYZ" is a tetradentate ligand.
In formula (B-1), M is preferably Ir and n is preferably 3 from the viewpoint of efficiency and life.
In formula (B-2), M is preferably Pt from the viewpoint of efficiency and life.
The ligand (XY) in formula (B-1) has at least one ligand selected from the group consisting of: The ligand (WXYZ) in formula (B-2) has as a part thereof at least one ligand selected from the group consisting of the following.

During the ceremony,
--- is bound to the central metal M,
Y is each independently BR _e , NR _e , PR _e , O, S, Se, C=O, S=O, SO2, CR _e R _f , SiRe _{R f} , or GeRe _{R f} each aromatic carbon C-H in the ring may be independently substituted with N,
R _e and R _f may optionally be fused or joined to form a ring;
R _a , R _b , R _c , and R _d are each independently unsubstituted or optionally substituted from 1 to the maximum possible number of substitutions;
R _a , R _b , R _c , R _d , R _e , and R _f are each independently hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, or combinations thereof;
However, any two adjacent substituents in R _a , R _b , R _c , and R _d may be fused or joined to form a ring or to form a multidentate ligand.

Examples of compounds represented by formula (B-1) include Ir(ppy) ₃ , Ir(ppy) ₂ (acac), Ir(mppy) ₃ , Ir(PPy) ₂ (m-bppy), BtpIr ( acac), Ir(btp) ₂ (acac), Ir(2-phq) ₃ , Hex-Ir(phq) ₃ , Ir(fbi) ₂ (acac), fac-Tris(2-(3-p-xylyl) phenyl)pyridine iridium (III), Eu(dbm) ₃ (Phen), Ir(piq) ₃ , Ir(piq) ₂ (acac), Ir(Fliq) ₂ (acac), Ir(FIq) ₂ (acac), Ru(dtb-bpy) ₃ 2(PF ₆ ), Ir(2-phq) ₃ , Ir(BT) ₂ (acac), Ir(DMP) ₃ , Ir(Mphq) ₃ IR(phq) ₂ tpy, fac -Ir(ppy) _2Pc , Ir(dp) _PQ2 , Ir(Dpm)(Piq) ₂ , Hex-Ir(piq) ₂ (acac), Hex-Ir(piq) ₃ , Ir(dmpq) ₃ , Ir (dmpq) ₂ (acac), FPQIrpic, and the like.

Other compounds represented by formula (B-1) include, for example, the following formulas.

In addition, JP 2006-089398, JP 2006-080419, JP 2005-298483, JP 2005-097263, and JP 2004-111379, US Patent Application Publication No. 2019/ 0051845, etc., or Advanced Materials, 26: 7116-7121, NPG Asia Materials 13, 53 (2021), Applied Physics Letters, 117, 253301 (2020), Light-Emitting Diode - An The platinum complexes described in Outlook On the Empirical Features and Its Recent Technological Advancements, Chapter 5 may also be used.

[TADF material (thermally activated delayed phosphor)]
As the dopant material, it is also preferable to use the boron-containing polycyclic aromatic compounds described in WO 2015/102118, WO 2018/212169, WO 2020/162600, and the like. A polycyclic aromatic compound having boron atoms may be a phosphor or a TADF material (thermally activated delayed phosphor). The polycyclic aromatic compound having boron atoms is preferably a blue light-emitting compound.

By reducing the energy difference between the excited singlet state and the excited triplet state, the reverse intersystem crossing from the excited triplet state, which normally has a low transition probability, to the excited singlet state can be generated with high efficiency. luminescence (thermally activated delayed fluorescence, TADF) is expressed. In normal fluorescence emission, 75% of triplet excitons generated by current excitation pass through the thermal deactivation pathway and cannot be extracted as fluorescence. On the other hand, in TADF, all excitons can be used for fluorescence emission, and a highly efficient organic EL device can be realized.

Preferred examples of polycyclic aromatic compounds containing boron include compounds represented by the following formulas (12), (13) and (14).

A ring, B ring, C ring and D ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,
Y is B (boron);
X ¹ , X ² , X ³ and X ⁴ are each independently >O, >NR, >S or >Se, and R in >NR is substituted or unsubstituted aryl; substituted or unsubstituted heteroaryl or substituted or unsubstituted alkyl, and R in >NR is bonded to the A ring, B ring, C ring and/or D ring through a linking group or a single bond; may be
R ¹ and R ² are each independently hydrogen, alkyl having 1 to 6 carbon atoms, aryl having 6 to 12 carbon atoms, heteroaryl or diarylamino having 2 to 15 carbon atoms (wherein aryl is C 6 to 12 aryl) and
Z ¹ and Z ² are each independently a substituent selected from the substituent group Z, Z ¹ may be a linking group or a single bond to the A ring, Z ² is a linking group or may be attached to the C ring with a single bond, and
At least one hydrogen in the compound represented by formula (12) may be replaced with cyano, halogen or deuterium.

The substituents and Z ¹ and Z ² when the aryl ring or heteroaryl ring in the A ring, B ring, C ring and D ring of formula (12) are substituted are selected from the substituent group Z Substituents can be mentioned.

X ¹ , X ² , X ³ and X ⁴ in formula (12) are each independently >O, >NR, >S or >Se, and R in >NR is each independently aryl having 6 to 12 carbon atoms, heteroaryl having 2 to 15 carbon atoms, cycloalkyl having 3 to 12 carbon atoms or alkyl having 1 to 6 carbon atoms. As for aryl, heteroaryl, cycloalkyl or alkyl here, the description of each of the above substituents can be cited.
In the compound represented by formula (12), from the viewpoint of high TADF properties, Z ¹ and Z ² are optionally substituted diphenylamino or optionally substituted N-carbazolyl. is preferred, and diphenylamino, which may have a substituent, is more preferred. The diphenylamino which may have a substituent is preferably unsubstituted diphenylamino or diphenylamino having at least one alkyl of 1 to 4 carbon atoms, and is preferably unsubstituted diphenylamino or m Diphenylamino with at least one methyl in the or o-position is more preferred. From the viewpoint of ease of synthesis and emission wavelength, the aryl or heteroaryl rings other than Z ¹ and Z ² in the A, B, C and D rings are unsubstituted or have 1 to 6 carbon atoms. as other substituents, and it is more preferable that Z ¹ and Z ² are not substituted.
Examples of compounds represented by formula (12) are shown below.

In formulas (13) and (14),
A ¹¹ ring, A ²¹ ring, A ³¹ ring, B ¹¹ ring, B ²¹ ring, C ¹¹ ring and C ³¹ ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl is a ring,
Y ¹¹ , Y ²¹ and Y ³¹ are B (boron),
X ¹¹ , X ¹² , X ²¹ , X ²² , X ³¹ and X ³² are each independently >O, >NR, >S or >Se, and R in >NR is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl or substituted or unsubstituted alkyl, and R in >NR is a linking group or a single bond to form A ¹¹ ring, A ²¹ ring, A ³¹ ring, B ¹¹ ring, B ²¹ ring, C ¹¹ ring, and/or C ³¹ ring;
At least one hydrogen in the compounds represented by formulas (13) and (14) may be replaced with cyano, halogen or deuterium.

the aryl or heteroaryl ring in A ¹¹ ring, A ²¹ ring, A ³¹ ring, B ¹¹ ring, B ²¹ ring, C ¹¹ ring, and C ³¹ of formula (13) and formula (14) is substituted Substituents selected from the substituent group Z can be mentioned as the substituents when and Z ¹ and Z ² .

X ¹¹ , X ¹² , X ²¹ , X ²² , X ³¹ , and X ³² in formulas (13) and (14) are each independently >O, >NR, >S, or >Se; , the Rs in the above >NR are each independently aryl having 6 to 12 carbon atoms, heteroaryl having 2 to 15 carbon atoms, cycloalkyl having 3 to 12 carbon atoms or alkyl having 1 to 6 carbon atoms. .

Examples of compounds represented by Formula (13) or Formula (14) are shown below.

<Electron Injection Layer and Electron Transport Layer in Organic Electroluminescent Device>
The electron injection layer 107 plays a role of efficiently injecting electrons moving from the cathode 108 into the light emitting layer 105 or the electron transport layer 106 . The electron transport layer 106 plays a role of efficiently transporting 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 transport layer 106 and the electron injection layer 107 are formed by stacking and mixing one or more electron transport/injection materials, or by a mixture of an electron transport/injection material and a polymer binder.

The electron injection/transport layer is a layer in which electrons are injected from the cathode and is responsible for transporting the electrons. It is desirable that the electron injection efficiency is high and the injected electrons are efficiently transported. For this purpose, it is preferable to use a substance that has high electron affinity, high electron mobility, excellent stability, and does not easily generate trapping impurities during production and use. However, when considering the transport balance of holes and electrons, if the function mainly plays the role of efficiently preventing holes from the anode from flowing to the cathode side without recombination, the electron transport capacity is not so high. Even if it is not high, the effect of improving the luminous efficiency is equivalent to that of a material with a high electron transport ability. Therefore, the electron injection/transport layer in this embodiment may also have the function of a layer capable of efficiently blocking the movement of holes.

Materials (electron transport materials) forming the electron transport layer 106 or the electron injection layer 107 include compounds conventionally used as electron transport compounds in photoconductive materials, and those used in the electron injection layer and electron transport layer of organic EL elements. It can be used by arbitrarily selecting from among the known compounds that are known. It is also preferable to use the polycyclic aromatic compound of the present invention as a material for an electron transport layer.

Materials used for the electron transport layer or electron injection layer include compounds composed of aromatic rings or heteroaromatic rings composed of one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon and phosphorus, It preferably contains at least one selected from pyrrole derivatives, condensed ring derivatives thereof, and metal complexes having electron-accepting nitrogen. Specifically, condensed ring aromatic ring derivatives such as naphthalene and anthracene, styryl aromatic ring derivatives typified by 4,4'-bis(diphenylethenyl)biphenyl, perinone derivatives, coumarin derivatives, and naphthalimide derivatives. , quinone derivatives such as anthraquinone and diphenoquinone, phosphorus oxide derivatives, arylnitrile derivatives and indole derivatives. Examples of metal complexes having electron-accepting nitrogen include hydroxyazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes and benzoquinoline metal complexes. These materials may be used alone, but may be used in combination with different materials.

Specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, and oxadiazole. derivatives (1,3-bis[(4-t-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 oxine derivatives, quinolinol metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives (2,2'-bis(benzo[h]quinolin-2-yl)-9,9'-spirobifluorene, etc.), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (tris(N-phenylbenzimidazole- 2-yl)benzene, etc.), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives, terpyridine derivatives (1,3-bis(4′-(2,2′:6′2 "-terpyridinyl)) 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 , and bis-styryl derivatives.

Metal complexes having electron-accepting nitrogen can also be used, for example, quinolinol-based metal complexes, hydroxyazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, benzoquinoline metal complexes, and the like. can give.

Although the above materials can be used alone, they may be used in combination with different materials.

Borane derivatives, pyridine derivatives, fluoranthene derivatives, BO-based derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, arylnitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, and quinolinol derivatives, among the materials mentioned above. Metal complexes are preferred.

The electron-transporting layer or electron-injecting layer may further contain a substance capable of reducing the material forming the electron-transporting layer or electron-injecting layer. Various substances are used as the reducing substance as long as they have a certain reducing property. from the group consisting of earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes At least one selected can be preferably used.

Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (2.28 eV), Rb (2.16 eV) or Cs (1.95 eV), and Ca (2.95 eV). 9 eV), Sr (2.0 to 2.5 eV) or Ba (2.52 eV), and materials with a work function of 2.9 eV or less are particularly preferred. Among these, more preferred reducing substances are alkali metals of K, Rb or Cs, more preferably Rb or Cs, and most preferably Cs. These alkali metals have a particularly high reducing ability, and by adding a relatively small amount to the material forming the electron transport layer or the electron injection layer, it is possible to improve the emission luminance and extend the life of the organic EL device. As a reducing substance having a work function of 2.9 eV or less, a combination of two or more of these alkali metals is also preferable, particularly a combination containing Cs, such as Cs and Na, Cs and K, Cs and Rb, or A combination of Cs, Na and K is preferred. By containing Cs, the reduction ability can be efficiently exhibited, and by addition to the material forming the electron transport layer or the electron injection layer, the luminance of the organic EL device can be improved and the life of the device can be extended.

<Cathode in Organic Electroluminescent Device>
The cathode 108 serves to inject electrons into the light emitting layer 105 via the electron injection layer 107 and the electron transport layer 106 .

The material for forming the cathode 108 is not particularly limited as long as it can efficiently inject electrons into the organic layer, but the same material as the material for forming the anode 102 can be used. Metals such as tin, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium and magnesium or their alloys (magnesium-silver alloys, magnesium - indium alloys, aluminum-lithium alloys such as lithium fluoride/aluminum, etc.). Lithium, sodium, potassium, cesium, calcium, magnesium, or alloys containing these low work function metals are effective for increasing electron injection efficiency and improving device characteristics. However, these low work function metals are generally unstable in the atmosphere. In order to improve this point, for example, a method is known in which an organic layer is doped with a small amount of lithium, cesium, or magnesium to use a highly stable electrode. Other dopants can also be inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide and cesium oxide. However, it is not limited to these.

Furthermore, for electrode protection, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, or alloys using these metals, inorganic substances such as silica, titania and silicon nitride, polyvinyl alcohol, vinyl chloride A preferable example is lamination of a hydrocarbon-based polymer compound or the like. The method of manufacturing these electrodes is not particularly limited, either by resistance heating, electron beam deposition, sputtering, ion plating, coating, or the like, as long as it can provide electrical continuity.

<Method for producing organic electroluminescent element>
Each layer constituting the organic EL element is formed by depositing a material to constitute 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. can be formed by The thickness of each layer thus formed is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured with a crystal oscillation film thickness measuring device or the like. When thin film formation is performed using a vapor deposition method, the vapor deposition conditions vary depending on the type of material, the desired crystal structure and association structure of the film, and the like. Deposition conditions are generally boat heating temperature +50 to +400°C, degree of vacuum 10 ^-6 to 10 ^-3 Pa, deposition rate 0.01 to 50 nm/sec, substrate temperature -150 to +300°C, film thickness 2 nm to 5 μm. It is preferable to set appropriately within the range.

When a DC voltage is applied to the organic EL device thus obtained, it is sufficient to apply the positive polarity to the positive electrode and the negative polarity to the negative electrode. Light emission can be observed from the side (anode or cathode, and both). Further, this organic EL element emits light even when a pulse current or an alternating current is applied. Note that the AC waveform to be applied may be arbitrary.

Next, as an example of a method for producing an organic EL device, an organic EL device comprising an anode/hole injection layer/hole transport layer/light-emitting layer comprising a host material and a dopant material/electron transport layer/electron injection layer/cathode. The manufacturing method of is explained.

<Deposition method>
A thin film of an anode material is formed on a suitable substrate by a vapor deposition method or the like to prepare an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A host material and a dopant material are co-deposited thereon to form a thin film to form a light-emitting layer, an electron-transporting layer and an electron-injecting layer are formed on the light-emitting layer, and a thin film of a cathode material is formed by vapor deposition or the like. A target organic EL element is obtained by forming the material and using it as a cathode. In the production of the organic EL element described above, the order of production can be reversed to produce 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 in this order. is.

<Wet film formation method>
The wet film-forming method is carried out by preparing a low-molecular-weight compound capable of forming each organic layer of an organic EL element as a liquid composition for forming an organic layer, and using this. In the absence of a suitable organic solvent for dissolving this low-molecular-weight compound, a reactive compound obtained by substituting a reactive substituent on the low-molecular-weight compound can be used together with other monomers or main-chain polymers that have a solubility function. A composition for forming an organic layer may be prepared from a molecularized polymer compound or the like.

In the wet film-forming method, a coating film is generally formed through a coating step of applying an organic layer-forming composition to a substrate and a drying step of removing a solvent from the applied organic layer-forming composition. In the case where the polymer compound has a crosslinkable substituent (also referred to as a crosslinkable polymer compound), the drying step further crosslinks the polymer to form a crosslinked polymer. Depending on the difference in the coating process, the method using a spin coater is called the spin coating method, the method using a slit coater is the slit coating method, the method using a plate is gravure, offset, reverse offset, flexographic printing, and the method using an inkjet printer is the inkjet method. , the method of spraying in the form of a mist is called the spray method. The drying process includes methods such as air drying, heating, and drying under reduced pressure. The drying step may be performed only once, or may be performed multiple times using different methods and conditions. Also, different methods may be used in combination, such as firing under reduced pressure.

A wet film-forming method is a film-forming method using a solution, and includes, for example, some printing methods (inkjet methods), spin coating methods or casting methods, and coating methods. Unlike the vacuum evaporation method, the wet film formation method does not require the use of an expensive vacuum evaporation apparatus and can form a film under atmospheric pressure. In addition, the wet film formation method enables large-area production and continuous production, leading to a reduction in manufacturing costs.

On the other hand, lamination may be difficult with the wet film-forming method when compared with the vacuum deposition method. When preparing a laminated film using a wet film formation method, it is necessary to prevent the dissolution of the lower layer by the composition of the upper layer. solvent) is used. However, even with those techniques, it can be difficult to use wet deposition methods for all film applications.

Therefore, in general, a method is adopted in which only some layers are formed by a wet film formation method, and the remaining layers are formed by a vacuum vapor deposition method.

For example, the procedure for partially applying the wet film formation method to fabricate an organic EL element is shown below.
(Procedure 1) Film formation of anode by vacuum deposition method (Procedure 2) Film formation of hole injection layer forming composition containing hole injection layer material by wet film formation method (Procedure 3) Hole transport layer material Film formation by a wet film formation method of a composition for forming a hole transport layer containing a host material and a dopant material by a wet film formation method (Procedure 5) Electron transport layer (Procedure 6) Electron injection layer film formation by vacuum vapor deposition method (Procedure 7) Cathode film formation by vacuum vapor deposition method Through this procedure, anode/hole injection layer/hole transport An organic EL device comprising a layer/host material and dopant material comprising a luminescent layer/electron-transporting layer/electron-injecting layer/cathode is obtained.
Of course, the electron-transporting layer and the electron-injecting layer may also be formed by a wet film-forming method using a layer-forming composition containing an electron-transporting layer material and an electron-injecting layer material, respectively. In this case, it is preferable to use a means for preventing dissolution of the lower light-emitting layer or a means for forming a film from the cathode side in reverse to the above procedure.

<Other film forming methods>
A laser thermal lithography method (LITI) can be used to form a film from the composition for forming an organic layer. LITI is a method in which a compound adhered to a base material is thermally vapor-deposited with a laser, and an organic layer-forming composition can be used as the material applied to the base material.

<Optional step>
Appropriate treatment steps, washing steps, and drying steps may be appropriately added before and after each step of film formation. Examples of treatment steps include exposure treatment, plasma surface treatment, ultrasonic treatment, ozone treatment, cleaning treatment using an appropriate solvent, and heat treatment. Furthermore, a series of steps for fabricating a bank can also be mentioned.

A photolithography technique can be used to fabricate the bank. Positive resist materials and negative resist materials can be used as bank materials that can be used in photolithography. In addition, patternable printing methods such as ink jet method, gravure offset printing, reverse offset printing, and screen printing can also be used. In that case, a permanent resist material can also be used.

<Organic Layer Forming Composition Used in Wet Film Forming Method>
The composition for forming an organic layer is obtained by dissolving a low-molecular-weight compound capable of forming each organic layer of an organic EL element or a high-molecular-weight compound obtained by polymerizing the low-molecular-weight compound in an organic solvent. For example, the composition for forming a light-emitting layer includes at least one dopant material polycyclic aromatic compound (or polymer compound thereof) as a first component, at least one host material as a second component, and a third It contains at least one organic solvent as a component. The first component functions as a dopant component for the light-emitting layer obtained from the composition, and the second component functions as a host component for the light-emitting layer. The third component functions as a solvent that dissolves the first and second components in the composition, and provides a smooth and uniform surface profile during application due to the controlled evaporation rate of the third component itself.

<Organic solvent>
The composition for forming an organic layer contains at least one kind of organic solvent. By controlling the evaporation rate of the organic solvent during film formation, it is possible to control and improve the film formability, the presence or absence of defects in the coating film, the surface roughness, and the smoothness. In addition, when forming a film using an inkjet method, the stability of the meniscus at the pinhole of the inkjet head can be controlled, and the ejection property can be controlled and improved. In addition, by controlling the drying rate of the film and the orientation of the derivative molecules, the electrical properties, luminescence properties, efficiency and life of the organic EL device having an organic layer obtained from the composition for forming an organic layer are improved. can be done.

After film formation, the organic solvent is removed from the coating film by a drying process such as vacuum, reduced pressure, or heating. When heating is performed, it is preferable to perform the heating at a temperature not higher than the glass transition temperature (Tg) of at least one of the solutes + 30°C from the viewpoint of improving coating film properties. From the viewpoint of reducing residual solvent, it is preferable to heat at least one of the solutes at a glass transition point (Tg) of −30° C. or higher. Even if the heating temperature is lower than the boiling point of the organic solvent, the organic solvent is sufficiently removed because the film is thin. In addition, drying may be performed multiple times at different temperatures, and multiple drying methods may be used in combination.

(2) Specific Examples of Organic Solvents Examples of organic solvents used in the composition for forming an organic layer include alkylbenzene solvents, phenyl ether solvents, alkyl ether solvents, cyclic ketone solvents, aliphatic ketone solvents, and monocyclic solvents. Examples include, but are not limited to, ketone solvents, solvents having a diester skeleton, fluorine-containing solvents, and the like. Also, the solvents may be used singly or in combination.

<Optional component>
The composition for forming an organic layer may contain optional components as long as the properties thereof are not impaired. Optional components include binders and surfactants.

<Composition and physical properties of composition for forming organic layer>
The content of each component in the organic layer-forming composition is obtained from the good solubility, storage stability, and film-forming properties of each component in the organic layer-forming composition, and the organic layer-forming composition. Good film quality of the coating film, good dischargeability when using the inkjet method, good electrical properties, luminescence properties, efficiency and life of the organic EL element having an organic layer produced using the composition It is determined in consideration of the viewpoint of

The composition for forming an organic layer can be produced by appropriately selecting the above-described components by stirring, mixing, heating, cooling, dissolving, dispersing, and the like by a known method. After preparation, filtration, degassing (also referred to as degassing), ion exchange treatment, inert gas replacement/encapsulation treatment, and the like may be appropriately selected and performed.

<Application example of organic electroluminescence device>
The present invention can also be applied to a display device having an organic EL element, a lighting device having an organic EL element, or the like.
A display device or a lighting device including an organic EL element can be manufactured by a known method such as connecting the organic EL element according to the present embodiment and a known driving device, and can be manufactured by direct current driving, pulse driving, alternating current driving, or the like. It can be driven by appropriately using a known driving method.

Examples of display devices include panel displays such as color flat panel displays, and flexible displays such as flexible color organic electroluminescence (EL) displays (for example, JP-A-10-335066 and JP-A-2003-321546). (See Japanese Patent Laid-Open No. 2004-281086, etc.). Moreover, the display method of the display includes, for example, a matrix method and a segment method. Note that matrix display and segment display may coexist in the same panel.

In the matrix, pixels for display are arranged in a two-dimensional pattern such as a grid pattern or a mosaic pattern, and a set of pixels displays characters and images. The shape and size of the pixels are determined by the application. For example, in the image and character display of personal computers, monitors, and televisions, square pixels with a side of 300 μm or less are usually used, and in the case of a large display such as a display panel, a pixel with a side of mm order is used. become. In the case of monochrome display, pixels of the same color may be arranged, but in the case of color display, pixels of red, green, and blue are displayed side by side. In this case, there are typically delta type and stripe type. As a method for driving this matrix, either a line-sequential driving method or an active matrix method may be used. The line-sequential drive has the advantage of being simpler in structure, but considering the operating characteristics, the active matrix may be superior.

In the segment method (type), a pattern is formed so as to display predetermined information, and a predetermined area is illuminated. Examples include time and temperature displays in digital clocks and thermometers, operating state displays in audio equipment and electromagnetic cookers, and panel displays in automobiles.

Examples of lighting devices include lighting devices such as indoor lighting, backlights for liquid crystal display devices, and the like (for example, JP-A-2003-257621, JP-A-2003-277741, JP-A-2004-119211, and the like). etc.). Backlights are mainly used for the purpose of improving the visibility of display devices that do not emit light by themselves, and are used in liquid crystal display devices, clocks, audio devices, automobile panels, display boards, signs, and the like. In particular, as a liquid crystal display device, especially a backlight for a personal computer, for which thinning is a problem, it is difficult to reduce the thickness of the conventional method because it is made of a fluorescent lamp or a light guide plate. The backlight using the light-emitting element according to 1 is characterized by its thinness and light weight.

3-2. Other Organic Devices The polycyclic aromatic compound according to the present invention can be used for the production of organic field effect transistors, organic thin film solar cells, etc., in addition to the organic electroluminescence devices described above.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these. First, synthesis examples of polycyclic aromatic compounds are described below.

Synthesis of compound (10-1)

Under a nitrogen atmosphere, 65 g of 1,2-dibromobenzene, 77 g of aniline, 4.8 g of bis(dibenzylideneacetone)palladium(0)(Pd(dba) ₂ ), tri-t-butylphosphonium tetrafluoroborate (tBu ₃ P -HBF ₄ ), 79.4 g of sodium t-butoxide (NaOtBu) and 650 ml of toluene were placed in a flask and refluxed for 2 hours while stirring. After completion of the reaction, the reaction solution was cooled to room temperature, water and toluene were added, and the solution was separated. After that, the organic layer was purified with a silica gel short pass column (solvent: toluene) and then purified with silica gel column chromatography (solvent: toluene/heptane=1/1) to give intermediate compound N ¹ ,N ² -diphenylbenzene-. 63.7 g of 1,2-diamine were obtained.

Under a nitrogen atmosphere, 56 g of N ¹ ,N ² -diphenylbenzene-1,2-diamine, 43.1 g of 2-nitrophenylboronic acid, 4.1 g of methanesulfonic acid and 1680 ml of toluene were placed in a flask equipped with a Dean-Stark trap. After the reaction was completed, the reaction solution was cooled to room temperature, purified with a silica gel short pass column (solvent: toluene), and the obtained crude product was treated with a Solmix solvent. After washing, 48.6 g of the intermediate compound 2-(2-nitrophenyl)-1,3-diphenyl-2,3-dihydro-1H-benzo[d][1,3,2]diazaborol was obtained.

Under a nitrogen atmosphere, 36 g of 2-(2-nitrophenyl)-1,3-diphenyl-2,3-dihydro-1H-benzo[d][1,3,2]diazaborol and 84.5 g of triphenylphosphine and 1, 1,800 ml of 2,4-trichlorobenzene was put into a flask, stirred, and refluxed for 8 hours. After completion of the reaction, the solvent was removed by distillation under reduced pressure, followed by purification by silica gel column chromatography (solvent: toluene/heptane = 1/1), further washing with methanol solvent, intermediate compound 16-phenyl- 3.5 g of 10H,16H-dibenzo[c,f]benzo[4,5][1,3,2]diazaborol[1,2-a][1,5,2]diazabolepine are obtained.

1.4 g of 16-phenyl-10H,16H-dibenzo[c,f]benzo[4,5][1,3,2]diazaborol[1,2-a][1,5,2]diazabolepine under nitrogen atmosphere , 0.5 g of copper, 2.0 g of potassium carbonate and 35 ml of iodobenzene were placed in a flask and refluxed for 6 hours while stirring. After completion of the reaction, the reaction solution was cooled to room temperature and purified with a silica gel short pass column (solvent: toluene). Then, after performing silica gel column chromatography (solvent: toluene/heptane = 1/4), reprecipitation was performed several times with methanol, and further purification by sublimation was performed to obtain the target compound (10-1) (0.7 g ).

The structure of the compound of formula (10-1) was confirmed by MS spectrum and NMR measurements.
¹ H-NMR (CDCl ₃ ): δ = 7.97 (dd, 1H), 7.70 (d, 1H), 7.65 (dd, 1H), 7.55 (d, 1H), 7.49 ~7.42 (m, 4H), 7.38 ~ 7.24 (m, 4H), 7.15 (dd, 1H), 7.10 ~ 7.01 (m, 6H), 6.63 (t , 1H), 6.55 (d, 2H)

The glass transition temperature (Tg) of the compound of formula (10-1) was 93.7°C.
[Measurement equipment: Diamond DSC (manufactured by PERKIN-ELMER); Measurement conditions: cooling rate 200° C./Min., heating rate 10° C./Min.]

Synthesis of compound (10-49)

1.7 g of 16-phenyl-10H,16H-dibenzo[c,f]benzo[4,5][1,3,2]diazaborol[1,2-a][1,5,2]diazabolepine under nitrogen atmosphere , 1.24 g of 55% sodium hydride (NaH) and 77 ml of dimethylformamide (DMF) were placed in a flask and stirred at room temperature for 1 hour. After that, 3.8 g of 2-chloro-4,6-diphenyl-1,3,5-triazine was added, and the mixture was further stirred at room temperature for 64 hours. After completion of the reaction, water was gradually added while cooling in an ice-water bath, and the mixture was extracted with ethyl acetate. Then, the solvent in the organic layer was distilled off under reduced pressure, and the resulting crude product was purified by NH ₂ silica gel column chromatography (solvent: toluene/heptane = 1/2 (volume ratio)), and then washed several times with Solmix solvent. After reprecipitation and sublimation purification, the target compound (10-49) (1.4 g) was obtained.

The structure of the compound of formula (10-49) was confirmed by MS spectrum and NMR measurements.
¹ H-NMR (CDCl ₃ ): δ = 8.35 (d, 2H), 8.32 (d, 2H), 7.97 (dd, 1H), 7.76-7.74 (m, 2H) , 7.63 (d, 1H), 7.53-7.33 (m, 14H), 7.20-7.16 (m, 2H), 7.07-7.00 (m, 3H)

Synthesis of compound (20-1)

Under a nitrogen atmosphere, 33.5 g of 2-bromo-N,N-diphenylaniline, 19.2 g of 2-aminobiphenyl, 1.8 g of bis(dibenzylideneacetone)palladium(0)(Pd(dba) ₂ ), tri-t 1.8 g of -butylphosphonium tetrafluoroborate (tBu ₃ P-HBF ₄ ), 19.9 g of sodium t-butoxide (NaOtBu) and 302 ml of toluene were placed in a flask and refluxed for 4 hours with stirring. After completion of the reaction, the reaction solution was cooled to room temperature, water and toluene were added, and the solution was separated. After that, the organic layer was purified with a silica gel short-path column (solvent: toluene), and then purified with silica gel column chromatography (solvent: toluene/heptane=1/2) to obtain the intermediate compound N ¹ -([1,1' -biphenyl]-2-yl)-N ² ,N ² -diphenylbenzene-1,2-diamine (39.9 g).

Under a nitrogen atmosphere, a flask containing 16.8 g of N ¹ -([1,1'-biphenyl]-2-yl)-N ² ,N ² -diphenylbenzene-1,2-diamine and 420 ml of toluene was heated to -70°C. and 16 ml of a 2.6M hexane solution of n-butyllithium was added dropwise. After the dropwise addition was completed, the mixture was stirred at -70°C for 1 hour and at 0°C for 1 hour. After that, the mixture was cooled to −70° C. again, and a solution obtained by dissolving 10.2 g of boron tribromide in heptane was added dropwise. The reaction solution was then warmed to room temperature and stirred overnight at room temperature. After that, the solvent was once distilled off under reduced pressure. 504 ml of 1,2-dichlorobenzene, 11.1 g of N,N-diisopropylethylamine and 32.6 g of aluminum trichloride were added thereto and stirred at 160° C. for 6 hours. The reaction was cooled to room temperature and added to an ice-water solution of sodium acetate. Toluene was added to separate the layers. The organic layer was purified by silica gel short pass column (solvent: toluene) and then by silica gel column chromatography (solvent: toluene/heptane=1/3 (volume ratio)). The resulting crude product was dissolved in toluene, reprecipitated several times with Solmix, and further recrystallized several times from ethyl acetate. Finally, purification by sublimation was performed to obtain the target compound (20-1) (0.5 g).

The structure of the compound of formula (20-1) was confirmed by MS spectrum and NMR measurements.
¹ H-NMR (CDCl ₃ ): δ = 8.64 (d, 1H), 8.58 (d, 1H), 8.30 (d, 1H), 7.70 (d, 2H), 7.63 ~7.60 (m, 4H), 7.55 ~ 7.48 (m, 6H), 7.41 ~ 7.37 (m, 2H), 7.27 ~ 7.18 (m, 3H), 7 .06(d, 1H)

Synthesis of compound (20-17)

In the synthesis of compound (20-1), 16.8 g of N ¹ -([1,1′-biphenyl]-2-yl)-N ² ,N ² -diphenylbenzene-1,2-diamine was added to compound (Int- The target compound (20-17) (0.2 g) was obtained in the same manner except that 20-17) was changed to 20.8 g.

The target compound (20-17) was confirmed at m/z=575.2284 by LC-MS.

Synthesis of compound (10-33)

The target compound (10-33) (2.5 g) was obtained in the same manner as in the synthesis of compound (10-1) except that 168 g of compound (Int-I-mCP) was used instead of 35 ml of iodobenzene.

The target compound (10-33) was confirmed at m/z=765.3060 by LC-MS.

Synthesis of compound (20-79)

In the synthesis of compound (20-1), 16.8 g of N ¹ -([1,1′-biphenyl]-2-yl)-N ² ,N ² -diphenylbenzene-1,2-diamine was added to compound (Int- The target compound (20-79) (0.4 g) was obtained in the same manner except that 20-79) was changed to 21.0 g.

The target compound (20-79) was confirmed at m/z=740.2866 by LC-MS.

Synthesis of compound (10-82)

The target compound (10-82) (5.1 g) was obtained in the same manner as in the synthesis of compound (10-1), except that 190 g of compound (Int-I-DBF-Trz) was used instead of 35 ml of iodobenzene.

The target compound (10-82) was confirmed at m/z=756.2810 by LC-MS.

Other polycyclic aromatic compounds of the present invention can be synthesized by a method according to the synthesis examples described above by appropriately changing the raw material compounds.

Next, the evaluation of the basic physical properties of the compound of the present invention and the preparation and evaluation of an organic EL device using the compound of the present invention will be described. However, application of the compound of the present invention is not limited to the examples shown below, and the film thickness and constituent materials of each layer can be appropriately changed according to the basic physical properties of the compound of the present invention.

<Evaluation of evaporation type organic EL element>
Organic EL devices according to Examples and Comparative Examples were produced, and the external quantum efficiency at a luminance of 1000 cd/m ² and LT50 (500 cd/m ² when continuously driven at a current density at an initial luminance of 1000 cd/m ² time) was measured.

<Comparative Example RS-1>
A 26 mm×28 mm×0.7 mm glass substrate (manufactured by OptoScience Co., Ltd.) was used as a transparent support substrate, on which an ITO film having a thickness of 200 nm was formed by sputtering and polished to 50 nm. This transparent supporting substrate was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Shinku Co., Ltd.), and HAT-CN, HTL-1, TcTa, new-DABNA, ETL-1 and ET7 were respectively put into molybdenum vapor deposition. A tungsten vapor deposition boat containing LiF and aluminum, respectively, was equipped.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was evacuated to 5×10 ⁻⁴ Pa, and HAT-CN was first heated and evaporated to a thickness of 5 nm to form a hole injection layer. Next, HTL-1 is heated and vapor-deposited to a thickness of 90 nm to form a hole-transport layer 1, and TcTa is heated and vapor-deposited to a thickness of 10 nm to form a hole-transport layer 2. formed. Next, ETL-1 and new-DABNA were heated at the same time and evaporated to a thickness of 20 nm to form a light-emitting layer. The deposition rate was adjusted so that the weight ratio of ETL-1 to new-DABNA was approximately 99:1. Next, ETL-1 is heated and evaporated to a thickness of 20 nm to form an electron transport layer 1, and ET7 is heated and evaporated to a thickness of 10 nm to form an electron transport layer consisting of two layers. Layer 2 was formed. The deposition rate of each layer was 0.01-1 nm/sec. After that, LiF is heated and vapor-deposited at a deposition rate of 0.01 to 0.1 nm/sec so that the film thickness becomes 1 nm, and then aluminum is heated and vapor-deposited so that the film thickness becomes 100 nm to form a cathode. Then, an organic EL device was obtained. At this time, the deposition rate of aluminum was adjusted to 1 to 10 nm/sec.

<Examples and Comparative Examples>
Each element was produced by changing the hole transport layer 2, the light emitting layer, and the electron transport layer 1 of Comparative Examples to the respective materials and concentrations shown in Table 1. In Table 1, "Host 1" corresponds to the hole-transporting host material, and "Host 2" corresponds to the electron-transporting host material. Table 1 shows the evaluation results of each device.

As shown in Examples S-1 and S-2, the organic electroluminescence device using the compound of the present invention as a single host exhibited higher efficiency and longer life than Comparative Example RS-1. Similarly, as shown in Examples D-1 to D-5, organic electroluminescent devices utilizing the compounds of the present invention as either of the two hosts exhibit higher efficiency and longer lifetime than Comparative Example RD-1. was taken. The compounds of the present invention can also be utilized as a hole-transporting layer or an electron-transporting layer adjacent to the light-emitting layer due to their deep HOMO or shallow LUMO, high T1 energy and charge transport properties. Specifically, as shown in Examples HD-1 to HD-3, Example DE-1, Examples E-1 and E-2, and Examples H-1 and H-2, light emission The organic electroluminescent device used in the hole-transporting layer or charge-transporting layer adjacent to the layer provided high efficiency and long lifetime. Furthermore, as shown in Examples HD-1 and DE-1, the organic electroluminescence element used for the light-emitting layer and either the hole-transporting layer or the electron-transporting layer adjacent to the light-emitting layer has the highest efficiency. A long life was obtained. In addition, as shown in Examples HD-1 to HD-3, the compounds of the present invention have high T1 energies, and thus can be used as hosts for blue TADF dopants and blue phosphorescent dopants with high T1. can do.

The chemical structures in Table 1 are shown below.

<Comparative example RDT-1>
A 26 mm×28 mm×0.7 mm glass substrate (manufactured by Optoscience Co., Ltd.) is used as a transparent support substrate. This transparent supporting substrate was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Shinku Co., Ltd.), and a molybdenum vapor deposition boat containing HAT-CN, HTL-1, TcTa, ETL-1, and ET7, respectively, Equip a tungsten evaporation boat containing LiF and aluminum respectively.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber is evacuated to 5×10 ⁻⁴ Pa, and HAT-CN is first heated and vapor-deposited to a thickness of 5 nm to form a hole injection layer. Next, HTL-1 is heated and vapor-deposited to a thickness of 90 nm to form a hole-transport layer 1, and TcTa is heated and vapor-deposited to a thickness of 10 nm to form a hole-transport layer 2. to form Next, ETL-1 and new-DABNA are heated at the same time and evaporated to a thickness of 20 nm to form a light-emitting layer. The deposition rate is adjusted so that the weight ratio of ETL-1 to new-DABNA is approximately 99:1. Next, ETL-1 is heated and evaporated to a thickness of 20 nm to form an electron transport layer 1, and ET7 is heated and evaporated to a thickness of 10 nm to form an electron transport layer 2. do. The deposition rate of each layer is set to 0.01 to 1 nm/sec. After that, LiF is heated and vapor-deposited at a deposition rate of 0.01 to 0.1 nm/sec so that the film thickness becomes 1 nm, and then aluminum is heated and vapor-deposited so that the film thickness becomes 100 nm to form a cathode. and an organic EL element can be obtained. At this time, the deposition rate of aluminum is adjusted to 1 to 10 nm/sec.

The hole-transporting layer 2, light-emitting layer, and electron-transporting layer 1 of Comparative Example RDT-1 were changed to the respective materials and concentrations shown in Table 2 to fabricate devices of Examples DT-1 to 4.

The chemical structures of the compounds listed in Table 2 are shown below.

As described above, some of the compounds according to the present invention were evaluated as materials for organic EL devices, and were shown to be excellent materials. They are compounds having a similar structure as a whole and can be understood by those skilled in the art to be similarly excellent materials for organic EL devices.

REFERENCE SIGNS LIST 100 organic electroluminescent element 101 substrate 102 anode 103 hole injection layer 104 hole transport layer 105 light emitting layer 106 electron transport layer 107 electron injection layer 108 cathode

Claims (17)

A polycyclic aromatic compound having a structure consisting of one or more structural units represented by the following formula (1);

In formula (1),
A ring, B ring and C ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,
Y is >B-, >P-, >P(=O)- or >P(=S)-;
X is >C(-R ^x1 )-, >N- or >Si(-R ^x3 )-,
R ^X1 and R ^X3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl;
Z is >C(-R ^Z1 ) ₂ , >N-R ^Z2 , >O, >Si(-R ^Z3 ) ₂ or >S;
R ^Z1 , R ^Z2 and R ^Z3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl; forming a ring together with the bonding element and the B ring or C ring, with the proviso that two R ^Z1 may be bonded to each other and two R ^Z3 may be bonded to each other;
L is a linking group having the shortest number of atoms of 1 to 4 linking the A ring and Y,
L may be bonded to the A ring via a linking group or a single bond,
At least one hydrogen in the structure may be replaced with deuterium, cyano or halogen. 2. The polycyclic aromatic compound according to claim 1, wherein said structure consists of one structural unit represented by formula (1). 3. The polycyclic aromatic compound according to claim 1 or 2, wherein A ring, B ring and C ring are all substituted or unsubstituted benzene rings. L is >C(-R ^L1 ) ₂ , >N-R ^L2 , >O, >Si(-R ^L3 ) ₂ , >S, >C=CR ^L1 ₂ , >C=NR ^L2 , >C=O , >C=S, -φ-, -φ-C(-R ^L1 ) ₂ -, -φ-N(-R ^L2 )-, -φ-O-, -φ-Si(-R ^L3 ) ₂ - , -φ-S-, -φ-C (=CR ^L1 ₂ )-, -φ-C (=NR ^L2 )-, -φ-C (=O)- or -φ-C (=S)- can be,
R ^L1 , R ^L2 and R ^L3 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl, and are the same may be bonded to each other ^, and at least one of R ^L1 , R ^{L2 ,} and at least one of R ^L3 are each linked by a linking group or a single bond to ring A or may be bound to at least one of φ,
φ is a substituted or unsubstituted arylene or a substituted or unsubstituted heteroarylene, and the arylene and the heteroarylene both have bonds to two adjacent ring-constituting atoms;
The polycyclic aromatic compound according to any one of claims 1-3. 5. The polycyclic aromatic compound of claim 4, wherein L is >N--R ^L2 . 5. The polycyclic aromatic compound according to claim 4, wherein L is 1,2-phenylene. X is >N-;
The polycyclic aromatic compound according to any one of claims 1 to 6, wherein Z is >NR ^Z2 , >O, or >S. The polycyclic aromatic compound according to any one of claims 1 to 7, wherein Y is B. 2. The polycyclic aromatic compound according to claim 1, represented by any one of the following formulae.

2. The polycyclic aromatic compound according to claim 1, represented by the following formula.

An organic device material containing the polycyclic aromatic compound according to any one of claims 1 to 10. It has a pair of electrodes consisting of an anode and a cathode and an organic layer disposed between the pair of electrodes, wherein the organic layer contains the polycyclic aromatic compound according to any one of claims 1 to 10. , an organic electroluminescent device. 13. The organic electroluminescent device according to claim 12, wherein said organic layer is a light-emitting layer. 14. The organic electroluminescent device according to claim 13, wherein said light-emitting layer comprises said polycyclic aromatic compound as a host material and a dopant material. 13. The organic electroluminescent device according to claim 12, wherein said organic layer is an electron transport layer. 13. The organic electroluminescent device according to claim 12, wherein said organic layer is a hole transport layer. A display device or a lighting device comprising the organic electroluminescence device according to any one of claims 12 to 16.

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