JP2024012832A - Polycyclic aromatic compound - Google Patents

Abstract

To provide a novel compound suitable as a material for organic devices such as an organic EL device.SOLUTION: A polycyclic aromatic compound comprises a structure comprising one or more structural units represented by the formula (1) (where, A ring, B ring, C1 ring, and C2 ring each represent a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring, Y1 represents B or the like, X1 represents >N-RNX (RNX is substituted or unsubstituted aryl) or the like, Cy1 and Cy2 each represent substituted or unsubstituted aryl condensed with at least one cycloalkane, and at least one hydrogen in the structure may be optionally substituted with cyano, halogen, or deuterium).SELECTED DRAWING: None

Description

The present invention relates to polycyclic aromatic compounds. The invention particularly relates to polycyclic aromatic compounds containing nitrogen and boron. The present invention also relates to organic device materials, organic electroluminescent elements, display devices, and lighting devices containing the polycyclic aromatic compound.

Conventionally, display devices using light-emitting elements that emit electroluminescence have been studied in various ways because they can save power and be made thinner.Furthermore, organic electroluminescent elements made of organic materials can be easily made lighter and larger. As a result, it has been actively considered. In particular, we are developing organic materials that emit light such as blue, which is one of the three primary colors of light, and organic materials that have charge transport capabilities such as holes and electrons (which have the potential to become semiconductors and superconductors). Regarding development, research has been active so far, regardless of whether it is a high-molecular compound or a low-molecular compound.

An organic electroluminescent device has a structure consisting of a pair of electrodes consisting of an anode and a cathode, and one or more layers containing an organic compound and disposed between the pair of electrodes. Layers containing organic compounds include a light-emitting layer and a charge transport/injection layer that transports or injects charges such as holes and electrons, and various organic materials suitable for these layers have been developed.

Among them, Patent Document 1 discloses that polycyclic aromatic compounds containing boron are useful as materials for organic electroluminescent devices and the like. It has been reported that organic electroluminescent devices containing this polycyclic aromatic compound have good external quantum efficiency. Patent Document 2 describes that by introducing a cycloalkene structure into the molecule of the above-mentioned polycyclic aromatic compound, the sublimation temperature is lowered and the stability is increased.

International Publication No. 2015/102118 International Publication No. 2020/017931

As mentioned above, various materials have been developed for use in organic EL devices, but in order to increase the selection of materials for organic EL devices, it is desired to develop materials made of compounds different from conventional ones. There is.
An object of the present invention is to provide a novel compound useful as a material for organic devices such as organic EL elements.

The present inventors have made extensive studies to solve the above problems, and have found that by combining a specific condensed ring structure and substituents in the structure of the compound described in Patent Document 1, a polycyclic aromatic compound that provides high luminous efficiency, etc. We succeeded in producing a group of compounds. They also discovered that an excellent organic EL device can be obtained by arranging a layer containing this polycyclic aromatic compound between a pair of electrodes, thereby completing the present invention. That is, the present invention provides the following polycyclic aromatic compounds, and furthermore, organic device materials containing the following polycyclic aromatic compounds.

Specifically, the present invention has the following configuration.

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

In formula (1),
Ring A, Ring B, Ring C1, and Ring C2 are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,
Y ¹ is B, P, P=O, P=S, Al, Ga, As, Si-R ^YI , or Ge-R ^YG , and R ^YI and R ^YG are each substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl;
X ¹ is >O, >N-R ^NX , >C(-R ^CX ) ₂ , >Si(-R ^IX ) ₂ , >S, or >Se, and R ^NX , R ^CX , and R ^IX are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two of >C(-R ^CX ) ₂ R ^CX may be bonded to each other to form a ring, and two R ^IX of >Si(-R) ₂ may be bonded to each other to form a ring, R ^NX , at least one R ^CX , and At least one R ^IX may be bonded to at least one of ring A or ring B via a single bond or a linking group,
Cy ¹ and Cy ² are each independently substituted or unsubstituted aryl fused with at least one cycloalkane, and at least one hydrogen in the cycloalkane may have a substituent, At least one -CH ₂ - in the cycloalkane may be substituted with -O-,
At least one of the aryl rings or heteroaryl rings in the portion other than Cy ¹ and Cy ² of the structure may be fused with at least one cycloalkane, and at least one hydrogen in the cycloalkane has a substituent. and at least one -CH ₂ - in the cycloalkane may be substituted with -O-,
At least one hydrogen in the structure may be replaced with cyano, halogen, or deuterium.

式中、Ｍｅはメチルであり、＊は結合位置を示す。 <2> Cy ¹ and Cy ² are each independently represented by formula (C-1), formula (C-2), formula (C-3), or formula (C-4) The polycyclic aromatic compound according to <1>, which is a group;

In the formula, Me is methyl, and * indicates the bonding position.

<3> The polycyclic aromatic compound according to <1> or <2>, wherein both the C1 ring and the C2 ring are benzene rings, and Cy ¹ and Cy ² are both bonded to the para position of N. .

<4> The polycyclic aromatic compound according to <1> or <2>, wherein the structural unit represented by formula (1) is a structural unit represented by formula (2);

In formula (2), Cy ¹ , Cy ² , X ¹ and Y ¹ are respectively synonymous with Cy ¹ , Cy ² , X ¹ and Y ¹ in formula (1),
R ^Za is hydrogen or a substituent,
Z is each independently -C(-R ^Z )= or -N=, R ^Z is each independently hydrogen or a substituent, and Z=Z is each independently >N-R ^NZ , >O, >C(-R ^CZ ) ₂ , >Si(-R ^IZ ) ₂ , >S, or >Se, and R ^NZ , R ^CZ and R ^IZ each independently represent hydrogen, Substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two R ^CZ may be bonded to each other to form a ring. , two R ^IZ may be bonded to each other to form a ring,
At least one of the aryl rings or heteroaryl rings in the portion other than Cy ¹ and Cy ² of the structure may be fused with at least one cycloalkane, and at least one hydrogen in the cycloalkane has a substituent. and at least one -CH ₂ - in the cycloalkane may be substituted with -O-,
At least one hydrogen in the structure may be replaced with cyano, halogen, or deuterium.

式中、Ｒはそれぞれ独立して置換基であり、ｎは０～４の整数である。 <5> The polycyclic aromatic compound according to <4>, which includes a partial structure represented by formula (b-1), formula (b-17), or formula (b-18);

In the formula, each R is independently a substituent, and n is an integer of 0 to 4.

<6> The polycyclic aromatic compound according to <4> or <5>, wherein R ^Za is unsubstituted alkyl or alkyl-substituted diarylamino.
<7> The polycyclic aromatic compound according to any one of <4> to <6>, wherein X ¹ is >NR ^NX and R ^NX is substituted or unsubstituted aryl.

<8> The polycyclic aromatic compound according to <1>, which is represented by any one of the following formulas.

式中、Ｍｅはメチルであり、ｔＢｕはｔ－ブチルであり、Ｄは重水素である。

In the formula, Me is methyl, tBu is t-butyl, and D is deuterium.

<9> An organic device material containing the polycyclic aromatic compound according to any one of <1> to <8>.
<10> A polycyclic aromatic compound according to any one of <1> to <8>, comprising a pair of electrodes consisting of an anode and a cathode, and a light emitting layer disposed between the pair of electrodes, wherein the light emitting layer is the polycyclic aromatic compound according to any one of <1> to <8>. An organic electroluminescent device containing.
<11> The organic electroluminescent device according to <10>, wherein the light emitting layer contains a host and the polycyclic aromatic compound as a dopant.
<12> The organic electroluminescent device according to <11>, wherein the host is an anthracene compound, a fluorene compound, or a dibenzochrysene compound.
<13> A display device or a lighting device comprising the organic electroluminescent element according to any one of <10> to <12>.

The present invention provides a novel polycyclic aromatic compound useful as a material for organic devices such as organic electroluminescent elements. The polycyclic aromatic compound of the present invention can be used for manufacturing organic devices such as organic electroluminescent elements.

1 is a schematic cross-sectional view showing an example of an organic electroluminescent device. FIG. 2 is an energy level diagram showing the energy relationship between a host, an assisting dopant, and an emitting dopant of a TAF element using a general fluorescent dopant. FIG. 2 is an energy level diagram showing an example of the energy relationship between a host, an assisting dopant, and an emitting dopant in an organic electroluminescent device according to one embodiment of the present invention.

In the following, the present invention will be explained in detail. Although the constituent elements described below may be explained based on typical embodiments and specific examples, the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "~" means a range that includes the numerical values written before and after the "~" as lower and upper limits. Moreover, in the description of the structural formula in this specification, "hydrogen" means "hydrogen atom (H)", and "oxygen" means "oxygen atom (O)". Other elements may also be described in the same manner.

In this specification, "Me" is methyl, "Et" is ethyl, "nBu" is n-butyl (normal butyl), "tBu" is t-butyl (tertiary butyl), "iBu" is isobutyl, "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" represents mesityl (2,4,6-trimethylphenyl), "Ad" represents 1-adamantyl, "Tf" represents trifluoromethanesulfonyl, "TMS" represents trimethylsilyl, and "D" represents deuterium.
In this specification, an organic electroluminescent device may be referred to as an organic EL device.

In this specification, chemical structures and substituents may be expressed by the number of carbon atoms, but when a chemical structure is substituted with a substituent, or when a substituent is further substituted with a substituent, the number of carbon atoms is It refers to the number of carbon atoms in each group, and does not mean the total number of carbon atoms in the chemical structure and substituents, or the total number of carbon atoms in the substituents. For example, "substituent B having a carbon number Y substituted with a substituent A having a carbon number X" means that "substituent B having a carbon number Y" is substituted with "substituent A having a carbon number X". However, the carbon number Y is not the total carbon number of substituent A and substituent B. For example, "substituent B having carbon number Y and substituted by substituent A" means that "substituent B having carbon number Y" is substituted with "substituent A (of which the number of carbon atoms is not limited)". However, the carbon number Y is not the total carbon number of substituent A and substituent B.

Since the chemical structural formulas described in this specification (including general formulas drawn using Markush structural formulas such as formula (1) described later) are planar structural formulas, they are actually enantioisomers, diamants, etc. Various isomeric structures such as stereoisomers and rotamers may exist. In this specification, unless otherwise specified, the compounds described may have any isomeric structure conceivable from their planar structural formula, or may be mixtures of possible isomers in any ratio. It may be.

In this specification, many structural formulas of aromatic compounds are described. Aromatic compounds are described as a combination of double bonds and single bonds, but in reality, π electrons resonate, so even for a single substance, double bonds and single bonds alternate, etc. There are multiple resonance structures. In this specification, only one resonance structural formula is described for each substance, but unless otherwise specified, other resonance structural formulas that are organically equivalent are also included. This will be referred to in descriptions such as "Z=Z", which will be described later. That is, for example, regarding "Z=Z" in equation (2) described later, the following is an example. However, the present invention is not limited to this, and naturally applies not only to the one resonance structural formula described, but also to other possible equivalent resonance structural formulas.

In this specification, two expressions are used: ``may be'' and ``are not, or are'', but these two expressions have the same meaning.
As used herein, the term "adjacent groups" refers to two groups each bonding to two adjacent atoms (two atoms directly bonded by a covalent bond) in the structural formula.

<0. Description of rings and substituents>
First, details of the rings and substituents used in this specification will be explained below.
As used herein, the "aryl ring" includes, for example, an aryl ring having 6 to 30 carbon atoms, preferably an aryl ring having 6 to 16 carbon atoms, more preferably an aryl ring having 6 to 12 carbon atoms, and Particularly preferred are 6 to 10 aryl rings.

Specific "aryl rings" include a monocyclic benzene ring, a biphenyl ring, a fused bicyclic naphthalene ring, an indene ring, and a tricyclic terphenyl ring (m-terphenyl ring). phenyl, o-terphenyl, p-terphenyl), fused tricyclic ring systems such as acenaphthylene ring, fluorene ring, phenalene ring, phenanthrene ring, anthracene ring, fused tetracyclic ring system such as triphenylene ring, pyrene ring, naphthacene ring, Examples include chrysene ring, perylene ring which is a fused pentacyclic ring, and pentacene ring. Furthermore, the fluorene ring, benzofluorene ring, and indene ring include structures in which fluorene rings, benzofluorene rings, cyclopentane rings, and the like are spiro-bonded, respectively. In addition, typically, in the fluorene ring, benzofluorene ring, and indene ring, two of the two hydrogen hydrogens of methylene contained in the structure are each replaced with alkyl such as methyl as a substituent, resulting in a dimethylfluorene ring. , dimethylbenzofluorene ring, dimethylindene ring, etc. are preferable.

Examples of the "heteroaryl ring" include a heteroaryl ring having 2 to 30 carbon atoms, preferably a heteroaryl ring having 2 to 25 carbon atoms, more preferably a heteroaryl ring having 2 to 20 carbon atoms, and a heteroaryl ring having 2 to 30 carbon atoms. A heteroaryl ring having 2 to 15 carbon atoms is more preferred, and a heteroaryl ring having 2 to 10 carbon atoms is particularly preferred. Examples of the "heteroaryl ring" include, for example, a heterocycle containing, in addition to carbon, 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen as ring constituent atoms.

Specific "heteroaryl rings" include, for example, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, oxadiazole ring (furazane ring, etc.), thiadiazole ring, triazole ring, and tetrazole ring. 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, phthalazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, carboline ring, acridine ring, phenoxathiine ring, phenoxazine ring, phenothiazine ring, phenazine ring , fenazacillin ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, thianthrene ring, indolocarbazole ring, benzindolocarbazole ring, dibenzindrocarbazole ring , naphthobenzofuran ring, dioxine ring, dihydroacridine ring, xanthene ring, thioxanthene ring, dibenzodioxin ring, dioxaboranaphthoanthracene ring (5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene ring) etc.) etc. In addition, a dihydroacridine ring, a xanthene ring, and a thioxanthene ring are formed by substituting two of the two hydrogens of methylene with alkyl such as methyl as the first substituent described below, resulting in a dimethyldihydroacridine ring, a dimethyl Those having a xanthene ring, dimethylthioxanthene ring, etc. are also preferable. Bipyridine rings, phenylpyridine rings, and pyridylphenyl rings, which are bicyclic rings, and terpyridyl rings, bispyridylphenyl rings, and pyridyl biphenyl rings, which are tricyclic rings, are also included as "heteroaryl rings." Furthermore, the term "heteroaryl ring" includes a pyran ring.

Substituents herein may be substituted with further substituents. (Regarding substituents, it may be explained as "substituted or unsubstituted"). This means that at least one hydrogen of the substituent (“first substituent” or “first substituent”) is substituted with a further substituent (“second substituent” or “second substituent”) , or means not replaced. Regarding the first substituent (first substituent) and the second substituent (second substituent), each description in the specification can be referred to.

In this specification, the substituent group ZB is
Aryl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl and substituted silyl,
heteroaryl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl and substituted silyl;
Diarylamino optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl and substituted silyl (two aryls are bonded to each other via a linking group) good),
Diheteroarylamino optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, and substituted silyl (two heteroaryls are bonded to each other via a linking group) ),
Arylheteroarylamino optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, and substituted silyl (aryl and heteroaryl are linked to each other via a linking group) may be combined),
Diarylboryl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl and substituted silyl (two aryls are 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, diarylamino, cycloalkyl and substituted silyl;
cycloalkyl optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl and substituted silyl;
alkoxy optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, cycloalkyl and substituted silyl;
aryloxy optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl and substituted silyl;
It consists of arylthio optionally substituted with at least one group selected from the group consisting of aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, and substituted silyl, and substituted silyl.
Aryl, which is the second substituent in each group of substituent group ZB, may be further substituted with aryl, heteroaryl, alkyl, or cycloalkyl. Similarly, heteroaryl, which is the second substituent, is aryl, Optionally substituted with heteroaryl, alkyl, or cycloalkyl. Furthermore, the second substituent cycloalkyl may be substituted with alkyl.

In this specification, when the term "substituent" is used, unless otherwise specified, any group selected from substituent group ZB may be used. For example, when a group defined as "substituted or unsubstituted" is substituted, the group may be substituted with at least one group selected from substituent group ZB.

As used herein, "aryl" includes, for example, aryl having 6 to 30 carbon atoms, preferably aryl having 6 to 24 carbon atoms, more preferably aryl having 6 to 20 carbon atoms, and aryl having 6 to 16 carbon atoms. More preferred are aryls having 6 to 12 carbon atoms, particularly preferred are aryls having 6 to 10 carbon atoms, and most preferred are aryls having 6 to 10 carbon atoms.

Specific examples of "aryl" include monovalent groups of the above-mentioned "aryl ring", such as phenyl, which is a monocyclic system, and biphenylyl (2-biphenylyl, 3-biphenylyl, or 4-biphenylyl), which is a bicyclic system. biphenylyl), fused bicyclic ring systems naphthyl (1-naphthyl or 2-naphthyl), tricyclic ring systems terphenylyl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl), Phenyl-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, phenalen-(1- or 2-)yl, phenanthrene-(1-, 2-, 3-, 4-, or 9-)yl, or anthracene -(1-, 2-, or 9-)yl, the tetracyclic system quaterphenylyl (5'-phenyl-m-terphenyl-2-yl, 5'-phenyl-m-terphenyl-3- yl, 5'-phenyl-m-terphenyl-4-yl, or m-quaterphenyl), triphenylene-(1- or 2-)yl, pyrene-(1-, 2- or 4-)yl, or naphthacen-(1-, 2-, or 5-)yl, or perylene-(1-, 2-, or 3-)yl, or pentacen-yl, which is a fused pentacyclic ring system. (1-, 2-, 5-, or 6-)yl, etc. Other examples include monovalent groups such as spirofluorene.

In addition, the aryl as a second substituent includes aryl such as phenyl (specific examples are the groups mentioned above), alkyl such as methyl (specific examples are the groups mentioned below), and cycloalkyl such as cyclohexyl or adamantyl. Also included are structures substituted with at least one group selected from the group consisting of (specific examples will be described later).
An example thereof is a group in which the 9-position of fluorenyl as a 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. Such as Arylen.
A specific example of "arylene" is a divalent group obtained by removing one hydrogen from the above-mentioned "aryl" (monovalent group).

Examples of "heteroaryl" include heteroaryl having 2 to 30 carbon atoms, preferably heteroaryl having 2 to 25 carbon atoms, more preferably heteroaryl having 2 to 20 carbon atoms, and heteroaryl having 2 to 15 carbon atoms. Heteroaryl is more preferred, and heteroaryl having 2 to 10 carbon atoms is particularly preferred. Examples of the heteroaryl include, for example, a heterocycle containing 1 to 5 heteroatoms selected from oxygen, sulfur, nitrogen, etc. in addition to carbon as ring constituent atoms.

Specific examples of "heteroaryl" include monovalent groups of the "heteroaryl ring" described above, such as 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 , naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiinyl, phenoxazinyl, phenothiazinyl, phenazinyl, phenazasilinyl, indolizinyl, furanyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, naphthobenzofuranyl, thienyl, benzothienyl, Isobenzothienyl, dibenzothienyl, naphthobenzothienyl, benzophosphoryl, dibenzophosphoryl, monovalent group of benzophosphole oxide ring, monovalent group of dibenzophosphole oxide ring, furazanyl, thianthrenyl, indolocarbazolyl, benzoin These include dorocarbazolyl, dibenzoindrocarbazolyl, imidazolinyl, or oxazolinyl. Other examples include a monovalent group of spiro[fluorene-9,9'-xanthene], a monovalent group of spirobi[silafluorene], and a monovalent group of benzoselenophene.

In addition, the heteroaryl as a second substituent includes an aryl such as phenyl (specific examples are the groups mentioned above), an alkyl such as methyl (specific examples are the groups mentioned later), and a cyclo such as cyclohexyl or adamantyl. Also included are structures substituted with at least one group selected from the group consisting of alkyl (specific examples of which will be described later).
An example thereof is a group in which the 9-position of carbazolyl as a second substituent is substituted with aryl such as phenyl, alkyl such as methyl, or cycloalkyl such as cyclohexyl or adamantyl. Further, a group in which a nitrogen-containing heteroaryl such as pyridyl, pyrimidinyl, triazinyl, or carbazolyl is further substituted with phenyl or biphenylyl is also included in the heteroaryl as a 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 Examples include heteroarylene of numbers 2 to 10. Further, "heteroarylene" is a divalent group such as a heterocycle containing, for example, 1 to 5 heteroatoms selected from oxygen, sulfur, nitrogen, etc. in addition to carbon as ring constituent atoms.
A specific example of "heteroarylene" is a divalent group obtained by removing one hydrogen from the above-mentioned "heteroaryl" (monovalent group).

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

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

Specifically, the linking group includes >O, >N-R ^x , >C(-R ^x ) ₂ , -(C-R ^x )=(C-R ^x )-, >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 optionally substituted with alkyl, cycloalkyl, aryl, or heteroaryl. In addition, the _two ^{R X} in each of >C(-R ^x ) ₂ , -(C- ^{R x} )=(C- ^R may be bonded to each other to form a ring. X ^Y is >O, >N- ^RY , >C( ^-RY ) ₂ , >Si( ^-RY ) ₂ , >S, >CO, >CS, >SO, >SO ₂ , and >Se. and each R ^Y is independently alkyl, cycloalkyl, aryl, or heteroaryl, which may be optionally 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 the linking group include alkenylene. Any hydrogen of the alkenylene may be each independently substituted with R ^2X , and each R ^2X is independently alkyl, cycloalkyl, substituted silyl, aryl, and heteroaryl, which are alkyl, cycloalkyl, It may be substituted with substituted silyl or aryl. -(C-R ^x )=(C-R ^{x )} -, even if the two R good. That is, -(C-R ^x )=(C-R ^x )- may be arylene (such as 1,2-phenylene) or heteroarylene.

In addition, in this specification, when simply described as "diarylamino," "diheteroarylamino," or "arylheteroarylamino," unless otherwise specified, "the two aryls of the diarylamino are "The 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." The aryl may be bonded to each other via a linking group.''

"Alkyl" may be either straight chain or branched, and includes, for example, straight chain alkyl having 1 to 24 carbon atoms or branched chain alkyl having 3 to 24 carbon atoms. Alkyl having 1 to 18 carbon atoms (branched alkyl having 3 to 18 carbon atoms) is preferable, alkyl having 1 to 12 carbon atoms (branched alkyl having 3 to 12 carbon atoms) is more preferable, and alkyl having 1 to 8 carbon atoms is preferable. (branched alkyl having 3 to 8 carbon atoms) is more preferable, alkyl having 1 to 6 carbon atoms (branched alkyl having 3 to 6 carbon atoms) is particularly preferable, and alkyl having 1 to 5 carbon atoms (branched alkyl having 3 to 5 carbon atoms) is particularly preferable. (branched alkyl) is most preferred.

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

"Alkylene" is a divalent group obtained by removing any hydrogen from "alkyl", such as methylene, ethylene, and propylene.

"Cycloalkyl" includes cycloalkyl having 3 to 24 carbon atoms, cycloalkyl having 3 to 20 carbon atoms, cycloalkyl having 3 to 16 carbon atoms, cycloalkyl having 3 to 14 carbon atoms, and cycloalkyl having 5 to 10 carbon atoms. Examples include alkyl, cycloalkyl having 5 to 8 carbon atoms, cycloalkyl having 5 to 6 carbon atoms, and cycloalkyl having 5 carbon atoms. In this specification, cyclohexyl includes not only monocyclic cyclohexyl but also polycyclic cyclohexyl such as adamantyl, as listed below.

Specific examples of cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, bicyclo[1.1.0]butyl, bicyclo[1.1.1]pentyl, and 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, decahydroazulenyl, etc.
It is also preferable that cycloalkyl has an alkyl group having 1 to 5 carbon atoms (particularly methyl) as a substituent. Furthermore, as described above, cycloalkyl as the second substituent includes those having alkyl such as methyl as a substituent.

"Alkenyl" includes straight chain alkenyl having 2 to 24 carbon atoms or branched alkenyl having 4 to 24 carbon atoms. Alkenyl having 2 to 18 carbon atoms is preferred, alkenyl having 2 to 12 carbon atoms is more preferred, alkenyl having 2 to 6 carbon atoms is even more preferred, and alkenyl having 2 to 4 carbon atoms is particularly preferred. Regarding "alkenyl", the above explanation of "alkyl" can be referred to, and it is a group in which the C-C single bond in the structure of "alkyl" is replaced with a C=C double bond, and only one It also includes groups in which two or more single bonds are substituted with double bonds (also called alkadien-yl or alkatrien-yl).
Specific examples of "alkenyl" include vinyl, allyl, butadienyl, and the like.

"Alkenylene" is a divalent group obtained by removing any hydrogen from "alkenyl", and includes, for example, vinylene.

Regarding "alkynyl", the above explanation of "alkyl" can be referred to, and it is a group in which the C-C single bond in the "alkyl" structure is replaced with a C≡C triple bond, and only one is required. It also includes groups in which two or more single bonds are substituted with triple bonds (also called alkadiin-yl or alkatriin-yl).

Examples of "alkoxy" include straight chain alkoxy having 1 to 24 carbon atoms or branched chain alkoxy having 3 to 24 carbon atoms. Alkoxy having 1 to 18 carbon atoms (branched alkoxy having 3 to 18 carbon atoms) is preferable, alkoxy having 1 to 12 carbon atoms (branched alkoxy having 3 to 12 carbon atoms) is more preferable, and alkoxy having 1 to 6 carbon atoms is preferable. Alkoxy (branched alkoxy having 3 to 6 carbon atoms) is more preferred, and alkoxy having 1 to 5 carbon atoms (branched alkoxy having 3 to 5 carbon atoms) is particularly preferred.

Specific examples of alkoxy include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, t-amyloxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, and the like.

"Aryloxy" is a group in which the hydrogen of the --OH group is substituted with aryl, and the aryl and its preferred range can be cited from those explained above.

"Arylthio" is a group in which the hydrogen of the --SH group is substituted with aryl, and the aryl and its preferred range can be cited from those explained above.

Examples of the "substituted silyl" include silyl substituted with three substituents selected from the group consisting of alkyl, cycloalkyl, and aryl. Examples include trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, triarylsilyl, dialkylarylsilyl, and alkyldiarylsilyl.

"Trialkylsilyl" includes a group in which three hydrogens in silyl are each independently substituted with alkyl, and this alkyl and its preferred range are the groups explained as "alkyl" in the first substituent group above. can be quoted. Preferred alkyls for substitution are those having 1 to 5 carbon atoms, and specific examples include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, t-amyl, and the like.

Specific trialkylsilyl includes trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, trisec-butylsilyl, trit-butylsilyl, trit-amylsilyl, ethyldimethylsilyl, propyldimethylsilyl, and isopropyldimethyl. Silyl, butyldimethylsilyl, sec-butyldimethylsilyl, t-butyldimethylsilyl, t-amyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, t-butyldiethyl Silyl, t-amyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, t-butyldipropylsilyl, t-amyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropyl Silyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, t-butyldiisopropylsilyl, t-amyldiisopropylsilyl, and the like.

"Tricycloalkylsilyl" includes a group in which three hydrogens in a silyl group are each independently substituted with cycloalkyl, and this cycloalkyl and its preferable range are "cycloalkyl" in the first substituent described above. ” can be cited. Preferred cycloalkyl for substitution is cycloalkyl having 5 to 10 carbon atoms, specifically cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, 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, Examples include decahydronaphthalenyl and decahydroazulenyl.

Specific examples of tricycloalkylsilyl include tricyclopentylsilyl and tricyclohexylsilyl.

Specific examples of dialkylcycloalkylsilyl substituted with two alkyl and one cycloalkyl and alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyl are selected from the above-mentioned specific alkyl and cycloalkyl. Examples include silyl substituted with a group.

Specific examples of dialkylarylsilyl substituted with two alkyls and one aryl, alkyldiarylsilyl substituted with one alkyl and two aryls, and triarylsilyl substituted with three aryls include the above-mentioned specific alkyls. and silyl substituted with a group selected from aryl. Specific examples of triarylsilyl include triphenylsilyl.

Regarding the "aryl" in "diarylboryl" and its preferred range, the above explanation of aryl can be cited. In addition, these two aryls can be a single bond or a linking group (for example, -CH=CH-, -CR=CR-, -C≡C-, >NR, >O, >S, >C(-R ) ₂ , >Si(-R) ₂ , or >Se). Here, R in -CR=CR-, R in >N-R, R in >C(-R) ₂ , and R in >Si(-R) are aryl, heteroaryl, diarylamino, alkyl, alkenyl, alkynyl, cycloalkyl, alkoxy, or aryloxy, and at least one hydrogen in R may be further substituted with aryl, heteroaryl, alkyl, alkenyl, alkynyl, or cycloalkyl. Furthermore, two adjacent R's may be bonded to each other to form a ring to form cycloalkylene, arylene, or heteroarylene. For details of the substituents listed here, the description of each substituent described above can be cited. In addition, in the case where "diarylboryl" is simply described in this specification, unless otherwise specified, "the two aryls of diarylboryl may be bonded to each other via a single bond or a linking group." It is assumed that the following explanation is added.

In this specification, when two groups bond to the same atom are bonded to each other to form a ring, it means that the atom and the two groups form a ring. The two groups may be bonded by a single bond or a linking group (these are also 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-. Examples where the same atoms are carbon or silicon include the following structures. In addition, the R of -CHR-CHR-, the R of -CR ₂ -CR ₂ -, the R of -CR=CR-, the R of -N(-R)-, the R of -C(-R) ₂ -, and R in -Si(-R) ₂ - each independently represents hydrogen, aryl optionally substituted with alkyl or cycloalkyl, heteroaryl optionally substituted with alkyl or cycloalkyl, or cycloalkyl. Alkyl which may be substituted, alkenyl which may be substituted with alkyl or cycloalkyl, alkynyl which may be substituted with alkyl or cycloalkyl, or cycloalkyl which may be substituted with alkyl or cycloalkyl. . Furthermore, two adjacent R's may be bonded to each other to form a ring to form cycloalkylene, arylene, or heteroarylene.

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

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

<1. Polycyclic aromatic compounds>
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 already discovered that polycyclic aromatic compounds in which aromatic rings are linked with heteroelements such as boron, nitrogen, oxygen, and sulfur have a large HOMO-LUMO gap (band gap Eg in thin films). . This is because the six-membered ring containing the hetero element has low aromaticity, which suppresses the decrease in the HOMO-LUMO gap due to expansion of the conjugated system. It has also been found that the HOMO-LUMO gap can be changed arbitrarily depending on the type of hetero element and the connection method. This is thought to be due to the fact that the energies of HOMO and LUMO can be moved arbitrarily depending on the spatial extent and energy of the empty orbital or lone pair of the hetero element.

These polycyclic aromatic compounds have a narrow half-width of the fluorescence emission peak due to the localization of excited states SOMO1 and SOMO2 on each atom due to the electronic perturbation of the hetero element, making them suitable as dopants for organic EL devices. When used, luminescence with high color purity can be obtained. For the same reason, ΔE _S1T1 becomes small, exhibiting thermally activated delayed fluorescence, and high efficiency can be obtained when used as an emitting dopant in an organic EL device.

Furthermore, by introducing a substituent, the energies of HOMO and LUMO can be changed arbitrarily, so it is possible to optimize the ionization potential and electron affinity depending on the surrounding materials. In the present invention, by introducing a substituted or unsubstituted aryl condensed with a cycloalkane as a substituent, a structure that can provide higher external quantum efficiency and lower driving voltage to an organic EL element as an emitting dopant is created. Achieved.
However, the present invention is not particularly limited to these principles.

[Explanation of ring structure in compound]
In formula (1), ring A, ring B, ring C1, and ring C2 are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring. In formula (1), "A", "B", "C1", and "C2" in the circles represent the ring structure (a part containing an aryl ring or a heteroaryl ring and a substituent thereto) shown in each circle. It is a sign. In the structure represented by formula (1), a ring structure is formed by connecting at least three aromatic rings, which are ring A, ring B, and ring C1, with Y ¹ such as boron and a hetero element such as nitrogen. It has a built-in structure. The ring structure formed has a fused ring structure composed of at least five rings.

Ring A forms a trivalent group having bonds to three consecutive elements (preferably carbon) on the aryl ring or heteroaryl ring in its structure. These three bonds are used to bond to Y ¹ , N, and X ^{1 ,} respectively. The ring in which the ring constituent element is an element having the above three bonds in the A ring is preferably a 5-membered ring or a 6-membered ring, more preferably a 6-membered ring. This ring may be further fused with another ring. Examples of the 6-membered ring include a benzene ring, a pyridine ring, a pyrazine ring, and a pyrimidine ring. Examples of a 6-membered ring further fused with another ring include a naphthalene ring, a quinoline ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, and a fluorene ring. Examples of the 5-membered ring include a furan ring, a thiophene ring, a pyrrole ring, and a thiazole ring. Examples of a 5-membered ring further fused with another ring include a benzofuran ring, a benzothiophene ring, and an indole ring.

The aryl ring or heteroaryl ring in Ring A is preferably a benzene ring.

Ring B forms a divalent group having bonds to two elements (preferably carbon) adjacent to each other on the aryl ring or heteroaryl ring in its structure. Ring B is bonded to Y ¹ and X ¹ through the above two bonds. The ring in which the ring constituent element is an element having the above two bonds in ring B is preferably a 5-membered ring or a 6-membered ring. This ring may be further fused with another ring. Examples of the 6-membered ring include a benzene ring, a pyridine ring, a pyrazine ring, and a pyrimidine ring. Examples of 6-membered rings fused with other rings include naphthalene ring, quinoline ring, benzofuran ring, benzothiophene ring, indole ring, benzoselenophene ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, and fluorene ring. etc. Examples of the 5-membered ring include a furan ring, a thiophene ring, a pyrrole ring, a thiazole ring, and a selenophene ring. Examples of a 5-membered ring further fused with another ring include a benzofuran ring, a benzothiophene ring, an indole ring, an indene ring, and a benzoselenophene ring.

The aryl ring or heteroaryl ring in ring B is preferably a benzene ring, benzofuran ring, benzothiophene ring, indole ring, indene ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, or fluorene ring; A benzothiophene ring, an indole ring, a dibenzofuran ring, or a carbazole ring is more preferred, and a benzene ring, a benzofuran ring, or a benzothiophene ring is even more preferred. It is preferable that the benzofuran ring, benzothiophene ring, indole ring, and indene ring are each bonded to Y ¹ at the 2-position and to X ¹ at the 3-position. The dibenzofuran ring is preferably bonded to Y ¹ at the 2-position and to X ¹ at the 3-position. Preferably, each dibenzothiophene ring is bonded to Y ¹ at the 2-position and to X ¹ at the 1-position. It is preferable that the carbazole ring and the fluorene ring are each bonded to Y ¹ at the 3-position and to X ¹ at the 2-position.

It is also preferred that the aryl ring or heteroaryl ring in Ring B is fused with at least one cycloalkane, preferably one cycloalkane, as described below.

The C1 ring has bonds to two elements (preferably carbon) adjacent to each other on the aryl ring or heteroaryl ring in its structure, and also has Cy ¹ to another ring constituent element (preferably carbon). It forms a trivalent group having a bond that binds to. The C1 ring is bonded to Y ¹ and N through the two adjacent bonds described above. The ring in which the C1 ring includes an element having two adjacent bonds as a ring constituent element is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring. It is preferable that there is a ring constituent element having a bond bonding to Cy ¹ on the same ring (single ring). This ring may be further fused with another ring. Examples of the 6-membered ring include a benzene ring, a pyridine ring, a pyrazine ring, and a pyrimidine ring. Examples of 6-membered rings fused with other rings include naphthalene ring, quinoline ring, benzofuran ring, benzothiophene ring, indole ring, benzoselenophene ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, and fluorene ring. etc. Examples of the 5-membered ring include a furan ring, a thiophene ring, a pyrrole ring, a thiazole ring, and a selenophene ring. Examples of a 5-membered ring further fused with another ring include a benzofuran ring, a benzothiophene ring, an indole ring, an indene ring, and a benzoselenophene ring.

The aryl ring or heteroaryl ring in the C1 ring is preferably a benzene ring. In formula (1), Cy ¹ is preferably bonded to the para position of N bonded to the C1 ring.

The C2 ring has a bond bonded to N to an element (preferably carbon) on the ring of the aryl ring or heteroaryl ring in its structure, and also has a bond bonded to ^Cy2 to another ring constituent element (preferably carbon). It forms a divalent group having a bond for bonding. The ring whose ring constituent element is an element having a bond bonded to N in the C1 ring is preferably a 5-membered ring or a 6-membered ring, more preferably a 6-membered ring. It is preferable that there is a ring constituent element having a bond bonding to Cy ² on the same ring (single ring). This ring may be further fused with another ring. Examples of the 6-membered ring include a benzene ring, a pyridine ring, a pyrazine ring, and a pyrimidine ring. Examples of a 6-membered ring further fused with another ring include a naphthalene ring, a quinoline ring, a benzofuran ring, a benzothiophene ring, an indole ring, a benzoselenophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a carbazole ring. It will be done. Examples of the 5-membered ring include a furan ring, a thiophene ring, a pyrrole ring, a thiazole ring, and a selenophene ring. Examples of a 5-membered ring further fused with another ring include a benzofuran ring, a benzothiophene ring, an indole ring, an indene ring, and a benzoselenophene ring.

The aryl ring or heteroaryl ring in the C2 ring is preferably a benzene ring. In formula (1), Cy ² is preferably bonded to the para position of N bonded to the C2 ring.

Ring A, Ring B, Ring C1, and Ring C2 are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring, and the aryl ring and the heteroaryl ring have a substituent. You can leave it there. Examples of substituents for each include any substituent selected from substituent group ZB. Regarding the preferred range of substituents, reference can be made to the description of preferred substituents described below.

In particular, the substituent on the aryl ring or heteroaryl ring in ring A is preferably unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted diarylamino, such as unsubstituted alkyl, alkyl-substituted aryl, or alkyl-substituted diarylamino is more preferred, and unsubstituted alkyl or alkyl-substituted diarylamino is even more preferred. For example, when it is a benzene ring, it is preferable to have diphenylamino, which may be substituted with an alkyl such as methyl or t-butyl, or an alkyl such as methyl or t-butyl, as a substituent at the ^para position of Y 1 .

The substituent on the aryl ring or heteroaryl ring in ring B is preferably unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted diarylamino, and unsubstituted alkyl, alkyl-substituted aryl, alkyl-substituted Diarylamino is more preferred. It is also preferable that the aryl rings in aryl and diarylamino are cycloalkane-fused as described below. For example, when it is a benzene ring, it has diphenylamino, which may be substituted with an alkyl such as methyl or t-butyl, or an alkyl such as methyl or t-butyl, as a substituent at the para-position of ^Y 1 or the para-position of N. It is preferable. When it is a benzofuran ring, benzothiophene ring, indole ring, or indene ring, it is preferable to have an alkyl group such as methyl or t-butyl as a substituent at the 5-position. The indole ring and carbazole ring preferably have a substituted or unsubstituted aryl at nitrogen. Further, in the indene ring and the fluorene ring, two of the two hydrogens of methylene are preferably replaced with methyl, respectively, to form a dimethylindene ring and a dimethylfluorene ring.

The aryl ring or heteroaryl ring in the C1 ring preferably has no substituents other than Cy ¹ . Further, it is preferable that the aryl ring or heteroaryl ring in the C2 ring has no substituent other than ^Cy2 .

[Description of Cy ¹ and Cy ² ]
Cy ¹ and Cy ² are substituted or unsubstituted aryl condensed with a cycloalkane as described below. The aryl here is preferably phenyl, 4-biphenylyl, or 4-p-terphenylyl, more preferably phenyl or 4-biphenylyl, and even more preferably phenyl.
Cy ¹ and Cy ² are preferably groups represented by any of the following formula (C-1), formula (C-2), formula (C-3), or formula (C-4), A group represented by formula (C-1) or formula (C-2) is more preferable, and a group represented by formula (C-1) is most preferable. In the following formula, * indicates a bonding position. show.

Cy ¹ and Cy ² may be the same or different, but are preferably the same.

[Cycloalkane condensation]
Cy ¹ and Cy ² are each independently substituted or unsubstituted aryl fused with at least one cycloalkane, and at least one -CH ₂ - in the cycloalkane is substituted with -O-. You can leave it there. Also, selected from the group consisting of aryl rings and heteroaryl rings in parts other than Cy ¹ and Cy ² in a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1) At least one of the cycloalkanes may be condensed with at least one cycloalkane, and at least one -CH ₂ - in the cycloalkane may be substituted with -O-. In this specification, "cycloalkane condensation" refers to condensation of at least one -CH ₂ - to a cycloalkane which may be substituted with -O-. It is expressed as By condensing an aryl ring and a heteroaryl ring with a cycloalkane, a cycloalkene structure is formed in which the bond shared with the aromatic ring becomes a double bond in the cycloalkane.

Preferred examples of the cycloalkane include cycloalkanes having 3 to 24 carbon atoms, and more preferred examples include cycloalkanes having 3 to 20 carbon atoms, cycloalkanes having 3 to 16 carbon atoms, and cycloalkanes having 3 to 14 carbon atoms. Examples include cycloalkane, cycloalkane having 5 to 10 carbon atoms, cycloalkane having 5 to 8 carbon atoms, cycloalkane having 5 to 6 carbon atoms, and cycloalkane having 6 carbon atoms.

Specific cycloalkanes include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, bicyclo[1.1.0]butane, bicyclo[1.1.1]pentane, and bicyclo[ 2.1.0] pentane, bicyclo[2.1.1]hexane, bicyclo[3.1.0]hexane, bicyclo[2.2.1]heptane, bicyclo[2.2.2]octane, adamantane, Examples include diamantane, decahydronaphthalene and decahydroazulene, as well as alkyl (especially methyl) substituted products having 1 to 5 carbon atoms, halogen (especially fluorine) substituted products and deuterium substituted products thereof.

Among these, for example, as shown in the structural formula below, the α-position carbon of a cycloalkane (in a cycloalkane fused to an aryl ring or heteroaryl ring, the carbon at the position adjacent to the carbon at the condensation site, corresponding to the benzyl position) ) is preferred, a structure in which at least one hydrogen is substituted, a structure in which two hydrogens are substituted in the α-position carbon is more preferred, and a structure in which a total of four hydrogens in two α-position carbons are substituted is still more preferred. . This is to protect chemically active sites and improve the durability of the compound. Examples of the substituent include an alkyl (especially methyl) substituent having 1 to 5 carbon atoms, a halogen (especially fluorine) substituent, and a deuterium substituent. In particular, it has a structure in which a partial structure represented by the following formula (Z-11) or formula (Z-12), preferably formula (Z-11), is bonded to adjacent carbon atoms in the aryl ring or heteroaryl ring. Preferably.

式（Ｚ－１１）、式（Ｚ－１２）中、Ｍｅはメチルを示し、＊は結合位置を示す。

In formula (Z-11) and formula (Z-12), Me represents methyl, and * represents the bonding position.

The number of cycloalkanes fused to one aryl ring or heteroaryl ring is preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. For example, an example in which one or more cycloalkanes are condensed to one benzene ring (phenyl) is shown below. * indicates a bonding position, and the position may be any carbon that constitutes a benzene ring and does not constitute a cycloalkane. Condensed cycloalkanes as shown in formula (Cy-1-4) and formula (Cy-2-4) may be condensed with each other. Even if the ring (group) to be condensed is an aryl ring or heteroaryl ring other than a benzene ring (phenyl), or if the cycloalkane to be condensed is a cycloalkane other than cyclopentane or cyclohexane, The same is true.

At least one --CH ₂ -- in the cycloalkane may be replaced with --O-. For example, an example in which one or more -CH ₂ - in a cycloalkane fused to one benzene ring (phenyl) is replaced with -O- is shown below. Even if the ring (group) to be condensed is an aromatic ring or heteroaromatic ring other than a benzene ring (phenyl), or if the cycloalkane to be condensed is another cycloalkane other than cyclopentane or cyclohexane. Even if there is, it is the same.

The cycloalkane may have a substituent, and examples of the substituent include any group selected from substituent group ZB. Among these substituents, alkyl (eg, alkyl having 1 to 6 carbon atoms) and cycloalkyl (eg, cycloalkyl having 3 to 14 carbon atoms) are preferred. Structures in which any hydrogen is replaced with halogen (eg, fluorine) and deuterium are also preferred. In addition, when cycloalkyl is substituted, a substitution form forming a spiro structure may be used, and an example of this is shown below.

Cycloalkane condensation, other than cycloalkane condensation with Cy ¹ and Cy ² , includes A ring in a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1), Examples include a form in which the aryl ring or heteroaryl ring in any one of the B ring, C1 ring, or C2 ring is fused with a cycloalkane. Particularly preferred is a form in which the aryl ring or heteroaryl ring in ring B is fused with a cycloalkane.

As another form of cycloalkane condensation, in a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1), any ring in X ¹ is cycloalkane condensation. One example is the form of ^For example, the aryl or heteroaryl ring in R ^NX , R CX , R IX in >NR ^NX , >C(-R ^CX ) ₂ , >Si(-R ^IX ) ₂ , where ^{X 1} is Examples include cycloalkane condensation of the aryl ring or heteroaryl ring in ^NX .

Note that the polycyclic aromatic compound of the present invention can be expected to have a lower melting point and sublimation temperature by introducing cycloalkane condensation. This means that in sublimation purification, which is almost essential as a purification method for materials for organic devices such as organic EL elements that require high purity, thermal decomposition of the material can be avoided because purification can be performed at a relatively low temperature. means. This also applies to the vacuum evaporation process, which is an effective means for producing organic devices such as organic EL elements, and because the process can be carried out at relatively low temperatures, thermal decomposition of the material can be avoided. As a result, a high-performance organic device can be obtained. Furthermore, since the solubility in organic solvents is improved by introducing the cycloalkane structure, it can also be applied to device fabrication using a coating process. However, the present invention is not particularly limited to these principles.

[Explanation of X ¹ ]
X ¹ is >O, >N-R ^NX , >C(-R ^CX ) ₂ , >Si(-R ^IX ) ₂ , >S, or >Se, and R ^NX , R ^CX , and R ^IX are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two of >C(-R ^CX ) ₂ R ^CX may be bonded to each other to form a ring, and two R ^IX of >Si(-R) ₂ may be bonded to each other to form a ring, R ^NX , at least one R ^CX , and At least one R ^IX may be bonded to at least one of ring A or ring B via a single bond or a linking group.

In formula ( ¹ ), R ^NX of >N-R ^NX , which is , phenyl, naphthyl, biphenylyl, terphenylyl, dibenzofuranyl, or carbazolyl, and even more preferably phenyl, biphenylyl, or dibenzofuranyl. Further, the phenyl, the naphthyl, the biphenylyl, the terphenylyl, the quaterphenylyl, the dibenzofuranyl, the dibenzothiophenyl, the fluorenyl, and the carbazolyl each independently contain at least one group selected from substituent group ZB. It may have one substituent. As the substituent, aryl which may be substituted with alkyl or diarylamino which may be substituted with alkyl is preferred. Further, any aryl ring or heteroaryl ring may be cycloalkane-fused. The above phenyl, the above biphenylyl, the above terphenylyl and the above quaterphenylyl are preferably any of the following groups. In the following formula, * indicates the bonding position with N of >NR ^NX , which is X ¹ .

When the above phenyl, the above biphenylyl, the above terphenylyl, or the above quaterphenylyl has a substituent or is cycloalkane-fused, the following groups can be mentioned as some of the preferable examples.

In the above formula, * indicates the bonding position with N. p and q indicate the number of t-butyl atoms bonded to the ring constituent elements of the ring with the end of the bond inside, and are each independently an integer from 0 to 3. r indicates the number of methyls bonded to the ring constituent elements of the ring with the end of the bond inside, and each is an integer of 0 to 3 independently. In a ring to which both t-butyl and methyl are bonded, q+r<6.

In formula (1), X ¹ is preferably >NR ^NX .
In formula ( ¹ ), at least one of R NX , R IX and R ^CX in >N-R ^NX , >Si ⁽ -R ^IX ) ₂ and >C(-R ^CX ) ₂ where X ¹ is may be bonded to either ring A or ring B through a linking group or a single bond. The linking group is preferably -O-, -S-, or -C(-R ¹³ ) ₂ -. R ¹³ is hydrogen, alkyl or cycloalkyl. In particular, alkyl having 1 to 5 carbon atoms (eg, methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl) is preferred.

Furthermore, the above definition can also be expressed by a structure having a ring structure in which X ¹ >N-R ^NX is incorporated into the condensed ring A', as represented by the following formula (1-3-2). That is, it is a compound having an A' ring formed by condensing another ring such that X ¹ is incorporated into the A ring, which is a benzene ring, for example. The resulting fused ring A' is, for example, a carbazole ring, a phenoxazine ring, or a phenothiazine ring.

As an example, a form in which R ^NX of >NR ^NX is substituted or unsubstituted cycloalkyl and is bonded to ring A or ring B through a single bond is also preferred. As the cycloalkyl, substituted or unsubstituted cyclopentyl or substituted or unsubstituted cyclohexyl is preferred.

A particularly preferred example of the condensed ring formed as described above is a structure represented by formula (A11). In formula (A11), * represents "X ¹ R in at least one of >N-R ^NX , >Si(-R ^IX ) ₂ and >C(-R ^CX ) ₂ is A through a linking group or a single bond. The above definition "may be bonded to any one of the ring and the B ring" corresponds to a form in which the compound is bonded through a single bond. As mentioned above, in this case, the two carbons substituted with methyl are asymmetric carbons, and the compound represented by formula (1) may exist in diastereomers and enantiomers, but in formula (1), The represented compounds may be any of these isomers, or may be in the form of a mixture of possible isomers in any ratio.

In formula (A11), Me is methyl, and is bonded to one ring of the two rings to which X ¹ or X ² is bonded at the * and ** positions, and to the other ring at the *** position. .

式（Ａ１２）中、＊と＊＊の位置でＸ¹が結合する２つの環の一方の環に、＊＊＊の位置で他方の環に結合している。 Similarly, the following examples are given in which R ^NX in the above >NR ^NX is phenyl and is bonded to ring A or ring B through a single bond.

In formula (A12), X ¹ is bonded to one ring of the two rings at the * and ** positions, and to the other ring at the *** position.

By using the compound of the present invention having X ¹ >N-R ^NX in the above-mentioned preferred range as a light-emitting material in the production of devices, luminous efficiency and device life can be further improved.

R in >Si(-R ^IX ) ₂ which is X ¹ in formula (1) is hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted alkyl. It is cycloalkyl. In particular, aryl having 6 to 10 carbon atoms (such as phenyl, naphthyl, etc.), heteroaryl having 2 to 15 carbon atoms (such as carbazolyl, etc.), alkyl having 1 to 5 carbon atoms (such as methyl, ethyl, etc.) or 5 to 10 carbon atoms. cycloalkyl (preferably cyclohexyl or adamantyl) is preferred. When referring to "substituted or unsubstituted," the substituent (second substituent) is preferably aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl.It is also preferable that cycloalkane condensation is present. .

R in >C(-R ^CX ) ₂ which is X ¹ in formula (1) is hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted alkyl. It is cycloalkyl. In particular, aryl having 6 to 10 carbon atoms (for example, phenyl, naphthyl, etc.), heteroaryl having 2 to 15 carbon atoms (for example, carbazolyl, etc.), alkyl having 1 to 5 carbon atoms (for example, methyl, ethyl, etc.) or 5 to 10 carbon atoms. cycloalkyl (preferably cyclohexyl or adamantyl) is preferred. When referring to "substituted or unsubstituted," the substituent (second substituent) is preferably aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl.Also, when fused with cycloalkane, preferable.

[Explanation of Y ¹ ]
In formula (1), Y ¹ is each independently B, P, P=O, P=S, Al, Ga, As, Si-R ^YI , or Ge-R ^YG , and R ^YI and R ^YG is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl. Y ¹ is preferably B or P═O, and most preferably B. R ^YI and R ^YG are preferably aryl having 6 to 12 carbon atoms, alkyl having 1 to 6 carbon atoms, or cycloalkyl having 3 to 14 carbon atoms, such as aryl having 6 to 10 carbon atoms (for example, phenyl, naphthyl). etc.), alkyl having 1 to 5 carbon atoms (eg, methyl, ethyl, etc.), or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl and adamantyl).

[Formula (2): Preferred embodiment of formula (1)]
Formula (2) can be cited as a preferable embodiment of formula (1).

In formula (2), Cy ¹ , Cy ² , X ¹ and Y ¹ have the same meanings as Cy ¹ , Cy ² , X ¹ and Y ¹ in formula (1), respectively, and their preferred ranges are also the same. R ^Za is hydrogen or a substituent, and is preferably hydrogen, unsubstituted alkyl, or diarylamino optionally substituted with alkyl.
In formula (2), Z is each independently -C(-R ^Z )= or -N=. -N=Z is preferably 0 to 3 in each of the a ring and the b ring, more preferably 0 to 2, and even more preferably 0 to 1. Preferably, all Z's are -C(-R ^Z )=.

Each R ^Z is independently hydrogen or a substituent. Examples of the substituent include any substituent selected from substituent group ZB. For preferred substitution positions and preferred ranges of substituent types, reference can be made to the explanation of the substituents in formula (1). Preferably, R ^Z is hydrogen or is bonded to an adjacent R ^Z as described below. Two adjacent R ^Z may be bonded to each other to form an aryl ring or a heteroaryl ring with the two carbon atoms to which they are bonded, and the formed aryl ring or heteroaryl ring has a substituent, respectively. You may do so. Examples of the substituent at this time include any substituent selected from substituent group ZB. For preferred substitution positions and preferred ranges of substituent types, reference can be made to the explanation of the substituents in formula (1). Z=Z is each independently >N-R ^NZ , >O, >C(-R ^CZ ) ₂ , >Si(-R ^IZ ) ₂ , >S, or >Se, preferably >N-R ^NZ , It may be >O, >S, or >Se. R ^NZ , R ^CZ and R ^IZ are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two R ^CZ may be bonded to each other to form a ring, and two R ^IZ may be bonded to each other to form a ring. R ^NZ is preferably substituted or unsubstituted aryl.

An example of the structure of a ring containing Z is shown below. In addition, in the following formula, R is a substituent and has the same meaning as R ^Z , but does not mean hydrogen and does not mean a bond between R's. R ⁰ is hydrogen or a substituent, and has the same meaning as R ^Z , but does not mean that R ⁰ are bonded to each other. Further, n is an integer of 0 to 4, and R ^N and R ^c are hydrogen, aryl optionally substituted with alkyl or cycloalkyl, heteroaryl optionally substituted with alkyl or cycloalkyl, cycloalkyl or cycloalkyl which may be substituted with alkyl, and two R ^c may be bonded to each other to form a ring.

The structure of the ring containing Z (ring b) is preferably a benzene ring, benzofuran ring, benzothiophene ring, indole ring, indene ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, or fluorene ring; A benzothiophene ring, an indole ring, a dibenzofuran ring, or a carbazole ring is more preferred, and a benzene ring, a benzofuran ring, or a benzothiophene ring is preferred. The benzofuran ring is preferably bonded to X ¹ and Y ¹ in the form represented by formula (b-17), and the benzothiophene ring is preferably bonded to X ¹ and Y ¹ in the form represented by formula (b-18). It is preferable that it is bonded to.

In each of the above partial structures, R is preferably unsubstituted alkyl or diarylamino optionally substituted with alkyl. n is preferably 0 or 1. Preferably R ⁰ is hydrogen. R ^N is preferably aryl optionally substituted with alkyl or cycloalkyl. Preferably R ^c is methyl.

[Structure consisting of one 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) and its preferred form. Examples of the polycyclic aromatic compound having a structure consisting of one of the above structural units include polycyclic aromatic compounds represented by the formula explained above as the structural unit represented by formula (1). As a polycyclic aromatic compound having a structure consisting of two or more structural units represented by formula (1), a polycyclic aromatic compound represented by the formula explained above as a structural unit represented by formula (1) is used. Compounds that correspond to multimers of group compounds are mentioned. The multimer is preferably a dimer to hexamer, more preferably a dimer to trimer, and particularly preferably a dimer. The multimer may have 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 the plurality of unit structures. It may be in a form in which the rings are bonded together, or in a form in which arbitrary rings (rings A or B) included in the unit structure are condensed with each other. Further, the above unit structure may be in the form of a single bond or a plurality of linking groups such as alkylene having 1 to 3 carbon atoms, phenylene, naphthylene, etc. Among these, preferred is a form in which they are bonded so that they share a ring.

[Replacement with deuterium, cyano, or halogen]
In the structure consisting of one or more structural units represented by formula (1), and in its preferred form, all or part of hydrogen may be replaced with deuterium, cyano, or halogen.

For example, in a structure consisting of the structural unit represented by formula (1) and one or more of its preferred forms, A ring, B ring, C1 ring, C2 ring, substituents to these rings, R (=alkyl, cycloalkyl, aryl) when Y ¹ is Si-R or Ge-R, and hydrogen in G _A or G _B may be substituted with deuterium, cyano or halogen, among which Examples include embodiments in which all or part of hydrogen in aryl or heteroaryl is substituted with deuterium, cyano, or halogen. Halogen is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine, even more preferably fluorine. In particular, a form in which hydrogen is replaced with deuterium is preferred because it improves the stability of the compound. Preferably, one hydrogen is replaced with deuterium, more preferably multiple hydrogens are replaced with deuterium, even more preferably all hydrogens in the aromatic moiety are replaced with deuterium, and all hydrogens are replaced with deuterium. is most preferred.

[Preferred substituents]
In polycyclic aromatic compounds used as emitting dopants (in other compounds used as dopants), tertiary alkyl represented by the following formula (tR) as a substituent containing "alkyl" is an aryl ring or a heteroaryl ring. It is one of the particularly preferred substituents on a ring (such as an aryl ring or a heteroaryl ring in ring A or ring B). This is because such a bulky substituent increases the intermolecular distance, thereby improving the luminescence quantum yield (PLQY). Also preferred is a substituent in which a tertiary alkyl represented by formula (tR) is substituted with another substituent as a second substituent. Specifically, diarylamino substituted with tertiary alkyl represented by (tR), carbazolyl (preferably N-carbazolyl) substituted with tertiary alkyl represented by (tR), or (tR) Examples include benzocarbazolyl (preferably N-benzocarbazolyl) substituted with the tertiary alkyl represented by the formula. The substitution form of the group of formula (tR) on diarylamino, carbazolyl and benzocarbazolyl is such that some or all hydrogens of the aryl ring or benzene ring in these groups are substituted with the group of formula (tR). An example can be given.

In formula (tR), R ^a , R ^b , and R ^c are each independently alkyl having 1 to 24 carbon atoms, and any -CH ₂ - in the alkyl may be replaced with -O-. , the group represented by formula (tR) has * as the bonding position.

The "alkyl having 1 to 24 carbon atoms" for R ^a , R ^b and R ^c may be either a straight chain or a branched chain, for example, a straight chain alkyl having 1 to 24 carbon atoms or a branched alkyl having 3 to 24 carbon atoms. Chain alkyl, alkyl having 1 to 18 carbons (branched alkyl having 3 to 18 carbons), alkyl having 1 to 12 carbons (branched alkyl having 3 to 12 carbons), alkyl having 1 to 6 carbons (branched alkyl having 3 to 12 carbons) (branched alkyl having 3 to 6 carbon atoms) and alkyl having 1 to 4 carbon atoms (branched alkyl having 3 to 4 carbon atoms).

The total number of carbon atoms of R ^a , R ^b , and R ^c in formula (tR) of formula (1) is preferably 3 to 20 carbon atoms, particularly preferably 3 to 10 carbon atoms.

Specific alkyls of R ^a , R ^b , and R ^c include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t -pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl, 1- Methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, 3,5,5-trimethylhexyl, n-decyl, n-undecyl, Examples include 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl, and the like.

Examples of the group represented by formula (tR) include t-butyl, t-amyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1-dimethylbutyl, 1-ethyl-1- Methylbutyl, 1,1,3,3-tetramethylbutyl, 1,1,4-trimethylpentyl, 1,1,2-trimethylpropyl, 1,1-dimethyloctyl, 1,1-dimethylpentyl, 1,1- Dimethylheptyl, 1,1,5-trimethylhexyl, 1-ethyl-1-methylhexyl, 1-ethyl-1,3-dimethylbutyl, 1,1,2,2-tetramethylpropyl, 1-butyl-1- Methylpentyl, 1,1-diethylbutyl, 1-ethyl-1-methylpentyl, 1,1,3-trimethylbutyl, 1-propyl-1-methylpentyl, 1,1,2-trimethylpropyl, 1-ethyl- Examples include 1,2,2-trimethylpropyl, 1-propyl-1-methylbutyl, and 1,1-dimethylhexyl. Among these, t-butyl and t-amyl are preferred.

The emission wavelength can be adjusted by the steric hindrance, electron donating and electron withdrawing properties of the structure of the substituent of the compound used as a dopant (assisting dopant or emitting dopant). Preferably it is a group represented by the following structural formula, more preferably methyl, t-butyl, t-amyl, t-octyl, neopentyl, adamantyl, dimethyladamantyl, phenyl, o-tolyl, p-tolyl, 2 , 4-xylyl, 2,5-xylyl, 2,6-xylyl, 2,4,6-mesityl, diphenylamino, di-p-tolylamino, bis(p-(t-butyl)phenyl)amino, carbazolyl, 3 , 6-dimethylcarbazolyl, 3,6-di-t-butylcarbazolyl and phenoxy, more preferably methyl, t-butyl, t-amyl, t-octyl, neopentyl, adamantyl, phenyl, o -tolyl, 2,6-xylyl, 2,4,6-mesityl, diphenylamino, di-p-tolylamino, bis(p-(t-butyl)phenyl)amino, carbazolyl, 3,6-dimethylcarbazolyl, 3,6-di-t-butylcarbazolyl and tribenzazepinyl. From the viewpoint of ease of synthesis, those with greater steric hindrance are preferable for selective synthesis; specifically, t-butyl, t-amyl, t-octyl, adamantyl, dimethyladamantyl, o-tolyl, p-tolyl, 2,4-xylyl, 2,5-xylyl, 2,6-xylyl, 2,4,6-mesityl, di-p-tolylamino, bis(p-(t-butyl)phenyl)amino, 3 , 6-dimethylcarbazolyl and 3,6-di-t-butylcarbazolyl are preferred.

In the structural formula below, * represents the bonding position.

A polycyclic aromatic compound having a structure consisting of the structural unit represented by formula (1) and one or more of its preferred forms is a tertiary alkyl (t- It preferably has a structure containing at least one of neopentyl or adamantyl (such as butyl or t-amyl), and preferably contains a tertiary alkyl represented by formula (tR) (such as t-butyl or t-amyl). This is because such a bulky substituent increases the intermolecular distance, thereby improving the luminescence quantum yield (PLQY). Diarylamino is also preferred as a substituent. Further, diarylamino substituted with a group of formula (tR), carbazolyl (preferably N-carbazolyl) substituted with a group of formula (tR), or benzocarbazolyl (preferably N-carbazolyl) substituted with a group of formula (tR) Preferably, N-benzocarbazolyl) is also preferred. Examples of the substitution form of the group of formula (tR) on diarylamino, carbazolyl and benzocarbazolyl include examples in which the aryl ring of these groups is substituted with 1 to 3 groups of formula (tR).

[Specific examples of polycyclic aromatic compounds of the present invention]
Further specific examples of the polycyclic aromatic compound represented by formula (1) of the present invention include the following compounds. Note that the structure below is an example.

[Method for producing polycyclic aromatic compound]
The polycyclic aromatic compound of the present invention having a structure consisting of one or more structural units represented by formula (1) basically first connects ring A, ring B, and ring C1 with a bonding group. (a group containing > N ^{- R} The final product can be produced by bonding with (second reaction). For the first reaction, for example, a general reaction such as a nucleophilic substitution reaction or an Ullmann reaction can be used for an etherification reaction, and a general reaction such as a Buchwald-Hartwig reaction can be used for an amination reaction. Further, in the second reaction, a tandem hetero Friedel-Crafts reaction (continuous aromatic electrophilic substitution reaction, the same applies hereinafter) can be used. The desired compound can be produced by using a raw material having a desired condensed ring or by adding a step of condensing the rings at some point in the reaction process.

<Production method via intermediate-1>
The polycyclic aromatic compound of the present invention can be produced by a production method including the following steps. For each step below, reference can be made to the description in International Publication No. 2015/102118.

Specifically, a reaction step of metalating the halogen atom (Hal) in Intermediate 1 below using an organic alkali compound, a halide of ^Y1 , an aminated halide of ^Y1 , an alkoxylate of ^Y1 , and A reaction step of exchanging the metal with Y ¹ using a reagent selected from the group consisting of aryl oxides of Y ¹ , and a continuous aromatic electrophilic substitution reaction using a Brønsted ^base etc. A manufacturing method including a reaction step of bonding ring B and ring C is mentioned. The reaction is described below.

Examples of the metalation reagent used in the halogen-metal exchange reaction in the above production method include alkyllithium such as methyllithium, n-butyllithium, sec-butyllithium, and t-butyllithium, isopropylmagnesium chloride, isopropylmagnesium bromide, Examples include phenylmagnesium chloride, phenylmagnesium bromide, and a lithium chloride complex of isopropylmagnesium chloride known as Turbo Grignard reagent.

In addition to the above-mentioned reagents, the metalation reagents used in the orthometal exchange reaction in the above production method include lithium diisopropylamide, lithium tetramethylpiperidide, lithium hexamethyldisilazide, potassium hexamethyldisilazide. Examples include organic alkali compounds such as dido, lithium chloride, tetramethylpiperidinylmagnesium/lithium chloride complex, and lithium tri-n-butylmagnesiumate.

Furthermore, when using alkyl lithium as a metalation reagent, additives that promote the reaction include N,N,N',N'-tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, Examples include N,N-dimethylpropylene urea.

In addition, the Bronsted bases used in the above production method include diisopropylethylamine, triethylamine, tributylamine, 1,4-diazabicyclo[2.2.2]octane, N,N-dimethyl-p-toluidine, N,N -dimethylaniline, pyridine, 2,6-lutidine, 2,6-di-t-butylamine and the like.

In the continuous aromatic electrophilic substitution reaction in the above production method, a Lewis acid may be added to promote the reaction. Lewis acids used in the above production method include AlCl ₃ , AlBr ₃ , AlF ₃ , BF ₃・_OEt2 , _BCl3 , _BBr3 , _GaCl3 , _GaBr3 , _InCl3 , _InBr3 , In(OTf) ₃ , SnCl4 _{, SnBr4} , AgOTf, _ScCl3 , Sc(OTf) ₃ , _ZnCl2 , ZnBr ₂ , Zn(OTf) ₂ , MgCl ₂ , MgBr ₂ , Mg(OTf) ₂ , LiOTf, NaOTf, KOTf, Me ₃ SiOTf, Cu(OTf) ₂ , CuCl ₂ , YCl ₃ , Y(OTf) ₃ , TiCl ₄ , Examples include TiBr ₄ , ZrCl ₄ , ZrBr ₄ , FeCl ₃ , FeBr ₃ , CoCl ₃ and CoBr ₃ . Furthermore, solid supported Lewis acids can also be used. In addition, in this specification, "OTf" means a "trifluoromethylsulfonyl group" or trifluoromethylsulfonate.

In addition, the solvents used in the above production method include o-dichlorobenzene, chlorobenzene, toluene, benzene, methylene chloride, chloroform, dichloroethylene, benzotrifluoride, decalin, cyclohexane, hexane, heptane, 1,2,4-trimethylbenzene. , xylene, diphenyl ether, anisole, cyclopentyl methyl ether, tetrahydrofuran, dioxane, methyl-t-butyl ether and the like.

Here, we have described an example in which Y ¹ is B, but by appropriately changing the raw materials, Y ¹ can be changed to P, P=O, P=S, Al, Ga, As, Si-R, or Ge- Compounds in which R can also be synthesized.

The polycyclic aromatic compounds of the present invention also include compounds in which at least some of the hydrogen atoms are substituted with deuterium or cyano, and compounds in which halogens such as fluorine and chlorine are substituted. Compounds can be synthesized in the same manner as above by using raw materials that are deuterated, cyanated, fluorinated, or chlorinated at desired positions.

<2. Organic devices>
The polycyclic aromatic compound of the present invention can be used as a material for organic devices. Examples of the organic device include an organic electroluminescent element, an organic field effect transistor, and an organic thin film solar cell.

The polycyclic aromatic compound according to the present invention can be used as a material for organic devices. Examples of the organic device include an organic electroluminescent device, an organic field effect transistor, an organic thin film solar cell, etc., but an organic electroluminescent device is preferable. The polycyclic aromatic compound according to the present invention is preferably an organic electroluminescent device material, more preferably a light-emitting layer material (light-emitting material), and most preferably a dopant material for the light-emitting layer.

<2-1. Organic electroluminescent device>
<2-1-1. Structure of organic electroluminescent device>
FIG. 1 is a schematic cross-sectional view showing an example of an organic EL element.
The organic EL element 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 A hole transport layer 104 provided, a light emitting layer 105 provided on the hole transport layer 104, an electron transport layer 106 provided on the light emitting layer 105, and a light emitting layer 105 provided on the electron transport layer 106. It has an electron injection layer 107 and a cathode 108 provided on the electron injection layer 107.

Note that the organic EL element 100 can be manufactured in the reverse order, for example, by forming a substrate 101, a cathode 108 provided on the substrate 101, an electron injection layer 107 provided on the cathode 108, and an 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; It is also possible to have a configuration including a hole injection layer 103 provided on the hole injection layer 103 and an anode 102 provided on the hole injection layer 103.

All of the above layers are not indispensable, and the minimum structural unit is the anode 102, the light emitting layer 105, and the cathode 108. Layer 107 is an optional layer. Moreover, each of the above layers may be composed of a single layer or a plurality of layers.

In addition to the above-mentioned configuration of "substrate/anode/hole injection layer/hole transport layer/light emitting layer/electron transport layer/electron injection layer/cathode", examples of the layers constituting the organic EL element include " "Substrate/Anode/Hole transport layer/Light emitting layer/Electron transport layer/Electron injection layer/Cathode", "Substrate/Anode/Hole injection layer/Light emitting layer/Electron transport layer/Electron injection 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/Emissive layer/Electron transport layer/Electron injection layer/Cathode", "Substrate/Anode/Hole transport layer/Emissive layer/Electron injection layer/Cathode", "Substrate/Anode/Hole transport layer/Emissive layer/Electron "Transport layer/Cathode", "Substrate/Anode/Hole injection layer/Light emitting layer/Electron injection layer/Cathode", "Substrate/Anode/Hole injection layer/Light emitting layer/Electron transport layer/Cathode", "Substrate/Anode" /light emitting layer/electron transport layer/cathode" or "substrate/anode/light emitting layer/electron injection layer/cathode" may be used.

<2-1-2. Light-emitting layer in organic electroluminescent device>
The polycyclic aromatic compound of the present invention is preferably used as a material for forming any one or more organic layers in an organic electroluminescent device, and more preferably used as a material for forming a light emitting layer. 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 the electrodes to which an electric field is applied. The material for forming the light-emitting layer 105 may be any compound (luminescent compound) that emits light when excited by recombination of holes and electrons, can form a stable thin film shape, and is in a solid state. It is preferable that the compound is a compound that exhibits strong luminescence (fluorescence) efficiency. The polycyclic aromatic compound of the present invention can be used as a material for a light-emitting layer, and may also be used as a dopant material, or as a host material, but is preferably used as a material for a light-emitting layer, and as a dopant material. It is more preferable to use it as

In addition, as a dopant, there are examples in which an assisting dopant and an emitting dopant are used in combination, but in this specification, when simply described as "dopant", it refers to a light-emitting dopant used alone. .

The light-emitting layer may be a single layer or composed of multiple layers, and each is formed from a material for the light-emitting layer (host material, dopant material). The host material and the dopant material may each be one type or a combination of a plurality of types. The dopant material may be contained entirely or partially in the host material.

<Dopant material>
As a doping method, it can be formed by a co-evaporation method with a host material, but it may also be mixed with the host material in advance and then vapor-deposited at the same time. In the case where a plurality of dopants are used in combination, specific examples of dopants to be combined with the compound of the present invention are shown below.

The amount of dopant material to be used varies depending on the type of dopant material, and may be determined according to the characteristics of the dopant material. The amount of the dopant to be used is preferably 0.001 to 50% by mass, more preferably 0.05 to 20% by mass, and even more preferably 0.1 to 10% by mass based on the entire material for the light emitting layer. be. The above range is preferable in that, for example, concentration quenching phenomenon can be prevented.

<Host material>
Examples of host materials include fused ring derivatives such as anthracene, pyrene, dibenzochrysene, or fluorene, which have long been known as light emitters, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, and cyclopentadiene derivatives. , fluorene derivatives, benzofluorene derivatives, etc.

Further, as the host material, for example, a compound represented by any one of the following formulas (H1), (H2), and (H3) can be used.

In formulas (H1), (H2) and (H3), L ¹ represents arylene having 6 to 24 carbon atoms, heteroarylene having 2 to 24 carbon atoms, heteroarylene arylene having 6 to 24 carbon atoms, and arylene having 6 to 24 carbon atoms. Arylene Heteroarylene Arylene, preferably arylene having 6 to 16 carbon atoms, more preferably arylene having 6 to 12 carbon atoms, particularly preferably arylene having 6 to 10 carbon atoms, specifically, benzene ring, biphenyl ring, Examples include divalent groups such as terphenyl rings and fluorene rings. The heteroarylene is preferably a heteroarylene having 2 to 24 carbon atoms, more preferably a heteroarylene having 2 to 20 carbon atoms, even more preferably a heteroarylene having 2 to 15 carbon atoms, and particularly a heteroarylene having 2 to 10 carbon atoms. Preferably, specifically, a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring (such as a furazane ring), a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, and 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, phthalazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, acridine ring, phenoxathiine ring, phenoxazine ring, phenothiazine ring, phenazine ring, indolizine ring, furan ring, benzofuran divalent groups such as ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, and thianthrene ring. At least one hydrogen in the compound represented by each of the above formulas may be substituted with an alkyl having 1 to 6 carbon atoms, cyano, halogen, or deuterium.

Preferred specific examples include compounds represented by any of the structural formulas listed below. In the structural formulas listed below, at least one hydrogen may be substituted with halogen, cyano, alkyl having 1 to 4 carbon atoms (eg, methyl or t-butyl), phenyl, or naphthyl.

The amount of host material used varies depending on the type of host material, and may be determined depending on the characteristics of the host material. The amount of host material to be used is preferably 50 to 99.999% by mass, more preferably 80 to 99.95% by mass, and even more preferably 90 to 99.9% by mass of the entire material for the light emitting layer. It is.

<Anthracene compound>
Examples of the anthracene compound as a host include a compound represented by formula (3-H) and a compound represented by formula (3-H2).

In formula (3-H),
X and Ar ⁴ are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diarylamino, optionally substituted diheteroarylamino, substituted or unsubstituted Substituted arylheteroarylamino, substituted or unsubstituted alkyl, optionally substituted cycloalkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted Arylthio or substituted silyl, and all X and Ar ⁴ cannot be hydrogen at the same time.
At least one hydrogen in the compound represented by formula (3-H) is substituted with halogen, cyano, deuterium, or optionally substituted heteroaryl, or is unsubstituted.

Furthermore, a multimer (preferably a dimer) may be formed using the structure represented by formula (3-H) as a unit structure. In this case, for example, the unit structures represented by the formula (3-H) may be bonded to each other via (a group having a divalent bond such as a ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring, and a phenyl-substituted carbazole ring).

Details of each group in the compound represented by formula (3-H) can be cited from the explanation for formula (1) above, and will be further explained in the preferred embodiments section below.

Preferred embodiments of the anthracene compound will be described below. The definitions of the symbols in the structure below are the same as the definitions above.

In formula (3-H), X is each independently a group represented by formula (3-X1), formula (3-X2) or formula (3-X3), and formula (3-X1), formula The group represented by (3-X2) or formula (3-X3) is bonded to the anthracene ring of formula (3-H) at *. Preferably, two Xs do not simultaneously become groups represented by formula (3-X3). More preferably, two Xs do not simultaneously become groups represented by formula (3-X2).

Furthermore, a multimer (preferably a dimer) may be formed using the structure represented by formula (3-H) as a unit structure. In this case, for example, the unit structures represented by the formula (3-H) may be bonded to each other via (a group having a divalent bond such as a ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring, and a phenyl-substituted carbazole ring).

The naphthylene moiety in formula (3-X1) and formula (3-X2) may be fused with one benzene ring. The structure condensed in this way is as follows.

Ar ¹ and Ar ² are each independently hydrogen, phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or represented by formula (A) (including carbazolyl, benzocarbazolyl and phenyl-substituted carbazolyl). In addition, when Ar ¹ or Ar ² is a group represented by formula (A), the group represented by formula (A) is a group represented by formula (3-X1) or formula (3-X2) in its *. Combines with naphthalene ring.

Ar ³ is phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A) (carbazolyl, benzocarbazolyl and phenyl-substituted carbazolyl). In addition, when Ar ³ is a group represented by formula (A), the group represented by formula (A) is bonded to the single bond represented by the straight line in formula (3-X3) at its *. . That is, the anthracene ring of formula (3-H) and the group represented by formula (A) are directly bonded.

Furthermore, Ar ³ may have a substituent, and at least one hydrogen in Ar ³ may further include alkyl having 1 to 4 carbon atoms, cycloalkyl having 5 to 10 carbon atoms, phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl. , fluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A) (including carbazolyl and phenyl-substituted carbazolyl). In addition, when the substituent that Ar ³ has is a group represented by formula (A), the group represented by formula (A) is bonded to Ar ³ in formula (3-X3) at its *.

Ar ⁴ is each independently substituted with hydrogen, phenyl, biphenylyl, terphenylyl, naphthyl, or alkyl having 1 to 4 carbon atoms (methyl, ethyl, t-butyl, etc.) and/or cycloalkyl having 5 to 10 carbon atoms This is Cyril.

Examples of alkyl having 1 to 4 carbon atoms to be substituted on silyl include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, and cyclobutyl. is substituted with alkyl.

Specific examples of "silyl substituted with alkyl having 1 to 4 carbon atoms" include trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, trisec-butylsilyl, trit-butylsilyl, and ethyldimethylsilyl. , propyldimethylsilyl, isopropyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, t-butyl diethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, t-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, Examples include t-butyldiisopropylsilyl.

Cycloalkyl having 5 to 10 carbon atoms substituted with silyl includes cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, norbornenyl, 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, decahydronaphthalenyl, decahydro Examples include azulenyl, in which three hydrogens in silyl are each independently substituted with these cycloalkyl groups.

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

Substituted silyl also includes dialkylcycloalkylsilyl substituted with two alkyls and one cycloalkyl, and alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyls. Specific examples include the groups mentioned above.

Furthermore, hydrogen in the chemical structure of the anthracene compound represented by formula (3-H) may be substituted with a group represented by formula (A). When substituted with a group represented by formula (A), the group represented by formula (A) replaces at least one hydrogen in the compound represented by formula (3-H) at *.

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

In formula (A), Y is -O-, -S- or >N-R ²⁹ , and R ²¹ to R ²⁸ are each independently hydrogen, optionally substituted alkyl, or optionally substituted Cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted arylthio, trialkylsilyl, cycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, optionally substituted amino, halogen, hydroxy or cyano, and adjacent groups among R ²¹ to R ²⁸ are bonded to each other to form a hydrocarbon ring, It may form an aryl ring or a heteroaryl ring, and R ²⁹ is hydrogen or an optionally substituted aryl.
Y in formula (A) is preferably -O-.

The "alkyl" in "optionally substituted alkyl" in R ²¹ to R ²⁸ may be either straight chain or branched, for example, straight chain alkyl having 1 to 24 carbon atoms or straight chain alkyl having 3 to 24 carbon atoms. Examples include branched chain alkyl. Alkyl having 1 to 18 carbon atoms (branched alkyl having 3 to 18 carbon atoms) is preferable, alkyl having 1 to 12 carbon atoms (branched alkyl having 3 to 12 carbon atoms) is more preferable, and alkyl having 1 to 6 carbon atoms is preferable. (branched alkyl having 3 to 6 carbon atoms) is more preferred, and alkyl having 1 to 4 carbon atoms (branched alkyl having 3 to 4 carbon atoms) is particularly preferred.

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

The "cycloalkyl" of "optionally substituted cycloalkyl" in R ²¹ to R ²⁸ includes cycloalkyl having 3 to 24 carbon atoms, cycloalkyl having 3 to 20 carbon atoms, and cycloalkyl having 3 to 16 carbon atoms. , cycloalkyl having 3 to 14 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 examples of "cycloalkyl" include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and alkyl (especially methyl) substituted products of these having 1 to 4 carbon atoms, 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, decahydroazulenyl, and the like.

The "aryl" of "optionally substituted aryl" in R ²¹ to R ²⁸ includes, for example, aryl having 6 to 30 carbon atoms, preferably aryl having 6 to 16 carbon atoms, and preferably aryl having 6 to 12 carbon atoms. aryl having 6 to 10 carbon atoms is more preferred, and aryl having 6 to 10 carbon atoms is particularly preferred.

Specific examples of "aryl" include phenyl, which is a monocyclic system, biphenylyl, which is a bicyclic system, naphthyl, which is a fused bicyclic system, and terphenylyl, which is a tricyclic system (m-terphenylyl, o-terphenylyl, p-terphenylyl). , fused tricyclic ring systems such as acenaphthylenyl, fluorenyl, phenalenyl, and phenanthrenyl; fused tetracyclic ring systems such as triphenylenyl, pyrenyl, and naphthacenyl; and fused pentacyclic ring systems such as perylenyl and pentacenyl.

Examples of the "heteroaryl" of "optionally substituted heteroaryl" in R ²¹ to R ²⁸ include heteroaryl having 2 to 30 carbon atoms, preferably heteroaryl having 2 to 25 carbon atoms, and Heteroaryl having 2 to 20 carbon atoms is more preferred, heteroaryl having 2 to 15 carbon atoms is even more preferred, and heteroaryl having 2 to 10 carbon atoms is particularly preferred. Examples of the heteroaryl include, for example, a heterocycle containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen in addition to carbon as ring constituent 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, quinolyl, isoquinolyl, cinnolyl, quinazolyl, quinoxalinyl, phthalazinyl, napthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiinyl, phenoxazinyl, phenothiazinyl, Examples include phenazinyl, indolizinyl, furyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, thienyl, benzo[b]thienyl, dibenzothienyl, furazanyl, thianthrenyl, naphthobenzofuranyl, and naphthobenzothienyl.

Examples of the "alkoxy" in "optionally substituted alkoxy" in R ²¹ to R ²⁸ include straight chain alkoxy having 1 to 24 carbon atoms or branched chain alkoxy having 3 to 24 carbon atoms. Alkoxy having 1 to 18 carbon atoms (branched alkoxy having 3 to 18 carbon atoms) is preferable, alkoxy having 1 to 12 carbon atoms (branched alkoxy having 3 to 12 carbon atoms) is more preferable, and alkoxy having 1 to 6 carbon atoms is preferable. Alkoxy (branched alkoxy having 3 to 6 carbon atoms) is more preferred, and alkoxy having 1 to 4 carbon atoms (branched alkoxy having 3 to 4 carbon atoms) is particularly preferred.

Specific examples of "alkoxy" include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, and the like.

The "aryloxy" in the "optionally substituted aryloxy" in R ²¹ to R ²⁸ is a group in which the hydrogen of the -OH group is substituted with an aryl, and this aryl is the one in R ²¹ to R ²⁸ described above. Reference may be made to groups described as "aryl".

The "arylthio" in "optionally substituted arylthio" in R ²¹ to R ²⁸ is a group in which the hydrogen of the -SH group is substituted with aryl, and this aryl is the "arylthio" in "optionally substituted arylthio" in R ²¹ to R ²⁸ described above. ” can be cited.

The "trialkylsilyl" in R ²¹ to R ²⁸ includes a group in which each of the three hydrogen atoms in a silyl group is independently substituted with alkyl, and this alkyl is the same as the "alkyl" in R ²¹ to R ²⁸ described above. The groups described may be cited. Preferred alkyls for substitution are those having 1 to 4 carbon atoms, and specific examples include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, and cyclobutyl.

Specific examples of "trialkylsilyl" include trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, trisec-butylsilyl, trit-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyl Dimethylsilyl, sec-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, t-butyldiethylsilyl, methyldipropylsilyl, ethyldimethylsilyl Examples include propylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, t-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, t-butyldiisopropylsilyl, and the like.

The "tricycloalkylsilyl" in R ²¹ to R ²⁸ includes a group in which three hydrogens in a silyl group are each independently substituted with cycloalkyl, and this cycloalkyl is the "tricycloalkylsilyl" in R ²¹ to R ²⁸ described above. Reference may be made to the groups explained as "cycloalkyl". Preferred cycloalkyl for substitution is cycloalkyl having 5 to 10 carbon atoms, specifically cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, 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, Examples include decahydronaphthalenyl and decahydroazulenyl.

Specific examples of "tricycloalkylsilyl" include tricyclopentylsilyl, tricyclohexylsilyl, and the like.

Specific examples of dialkylcycloalkylsilyl substituted with two alkyl and one cycloalkyl and alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyl are selected from the above-mentioned specific alkyl and cycloalkyl. Examples include silyl substituted with a group.

Examples of the "substituted amino" of the "optionally substituted amino" in R ²¹ to R ²⁸ include amino in which two hydrogen atoms are substituted with aryl or heteroaryl. An amino in which two hydrogens are substituted with aryl is diaryl-substituted amino, an amino in which two hydrogens are substituted with heteroaryl is diheteroaryl-substituted amino, and an amino in which two hydrogens are substituted with aryl and heteroaryl. is an arylheteroaryl substituted amino. As the aryl and heteroaryl, the groups explained as "aryl" and "heteroaryl" in R ²¹ to R ²⁸ above can be cited.

Specific examples of the "substituted amino" include diphenylamino, dinaphthylamino, phenylnaphthylamino, dipyridylamino, phenylpyridylamino, naphthylpyridylamino, and the like.

Examples of the "halogen" for R ²¹ to R ²⁸ include fluorine, chlorine, bromine, and iodine.

Some of the groups described as R ²¹ to R ²⁸ may be substituted as described above, and the substituents in this case include alkyl, cycloalkyl, aryl, or heteroaryl. As the alkyl, cycloalkyl, aryl or heteroaryl, the groups explained as "alkyl", "cycloalkyl", "aryl" or "heteroaryl" in R ²¹ to R ²⁸ above can be cited.

R ²⁹ in “>NR ²⁹ ” as Y is hydrogen or an optionally substituted aryl, and as this aryl, the groups explained as “aryl” in R ²¹ to R ²⁸ above can be cited. As the substituent, the groups explained as substituents for R ²¹ to R ²⁸ can be cited.

Adjacent groups among R ²¹ to R ²⁸ may be bonded to each other to form a hydrocarbon ring, aryl ring or heteroaryl ring. A group that does not form a ring is a group represented by the following formula (A-1), and a group that does not form a ring is, for example, a group represented by the following formulas (A-2) to (A-14). It will be done. Note that at least one hydrogen in the group represented by any of formulas (A-1) to (A-14) is alkyl, cycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, arylthio, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, diaryl (two aryls may be unbonded to each other or bonded through a linking group) substituted amino, diheteroaryl substituted amino, aryl Heteroaryl may be substituted with amino, halogen, hydroxy or cyano.

Examples of the ring formed by bonding adjacent groups to each other include a cyclohexane ring in the case of a hydrocarbon ring, and examples of the aryl ring and heteroaryl ring include the above-mentioned "aryl" and "heteroaryl" in R ²¹ to R ²⁸ . These rings are formed so as to be fused with one or two benzene rings in formula (A-1).

The group represented by formula (A) is a group obtained by removing one hydrogen at any position in formula (A), and * indicates the position. That is, the group represented by formula (A) may be bonded to any position. For example, any carbon atom on two benzene rings in the structure of formula (A), or any carbon atom formed by bonding adjacent groups among R ²¹ to R ²⁸ in the structure of formula (A) ^an atom ^{on the} ring ^of It can be a group that directly binds to a hand). The same applies to groups represented by any of formulas (A-1) to (A-14).

Examples of the group represented by formula (A) include groups represented by any of formula (A-1) to formula (A-14), and formula (A-1) to formula (A-5). ) and groups represented by any one of formulas (A-12) to formula (A-14) are preferable, and groups represented by any one of formulas (A-1) to formula (A-4) are more preferable. , formula (A-1), formula (A-3) and formula (A-4) are more preferred, and the group represented by formula (A-1) is particularly preferred.

Examples of the group represented by formula (A) include the following groups. Y and * in the formula have the same definitions as above.

In the compound represented by formula (3-H), the group represented by formula (A) is a naphthalene ring in formula (3-X1) or formula (3-X2), or a naphthalene ring in formula (3-X3). A form in which Ar 3 in formula (3-X3) is bonded to any one of a single bond and Ar ³ in formula (3-X3) is preferable.

Furthermore, all or part of hydrogen in the chemical structure of the anthracene compound represented by formula (3-H) may be deuterium.

The anthracene compound as a host may be, for example, a compound represented by the following formula (3-H2).

In formula (3-H2), Ar ^c is optionally substituted aryl or optionally substituted heteroaryl, R ^c is hydrogen, alkyl, or cycloalkyl, and Ar ¹¹ , Ar ¹² , Ar ¹³ , Ar ¹⁴ , Ar ¹⁵ , Ar ¹⁶ , Ar ¹⁷ and Ar ¹⁸ are each independently hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted good diarylamino, optionally substituted diheteroarylamino, optionally substituted arylheteroarylamino, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl , optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted arylthio, or optionally substituted silyl, and at least one in the compound represented by formula (1) Hydrogen may be substituted with halogen, cyano, or deuterium.

In formula (3-H2), "optionally substituted aryl", "optionally substituted heteroaryl", "optionally substituted diarylamino", "optionally substituted dihetero arylamino,” “optionally substituted arylheteroarylamino,” “optionally substituted alkyl,” “optionally substituted cycloalkyl,” “optionally substituted alkenyl,” “substituted The definitions of "optionally substituted alkoxy", "optionally substituted aryloxy", "optionally substituted arylthio", or "optionally substituted silyl" are in the above formula (3-H). The explanation in equation (1) can be cited.

The "optionally substituted aryl" is also preferably a group represented by any of the following formulas (3-H2-X1) to (3-H2-X8).

In formulas (3-H2-X1) to (3-H2-X8), * indicates the bonding position. In formulas (3-H2-X1) to (3-H2-X3), Ar ²¹ , Ar ²² , and Ar ²³ each independently represent hydrogen, phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, It is phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, anthracenyl, or a group represented by formula (A). In the description of formula (3-H2), the group represented by formula (A) is the same as that described in the anthracene compound represented by formula (3-H).

In formulas (3-H2-X4) to (3-H2-X8), Ar ²⁴ , Ar ²⁵ , Ar ²⁶ , Ar ²⁷ , Ar ²⁸ , Ar ²⁹ and Ar ³⁰ each independently represent hydrogen, phenyl , biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A). Furthermore, any one or more hydrogens in each of the groups represented by formulas (3-H2-X1) to (3-H2-X8) are alkyl having 1 to 6 carbon atoms (preferably methyl or t-butyl).

Further, preferable examples of "optionally substituted aryl" are selected from the group consisting of phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, chrysenyl, triphenylenyl, pyrenyl, and the group represented by formula (A). Examples include terphenylyl (especially m-terphenyl-5'-yl), which may be substituted with one or more substituents.

The "optionally substituted heteroaryl" also includes a group represented by formula (A). In addition, specific examples of "optionally substituted aryl" and "optionally substituted heteroaryl" include dibenzofuryl, naphthobenzofuryl, phenyl-substituted dibenzofuryl, and the like.

At least one hydrogen in the compound represented by formula (1) may be substituted with halogen, cyano, or deuterium. Examples of "halogen" in this case include fluorine, chlorine, bromine, and iodine. Particularly preferred is a compound represented by formula (3-H2) in which all hydrogen atoms are replaced with deuterium.

In formula (3-H2), R ^c is hydrogen, alkyl, or cycloalkyl, preferably hydrogen, methyl, or t-butyl, and more preferably hydrogen.
In formula (3-H2), at least two of Ar ¹¹ to Ar ¹⁸ are preferably optionally substituted aryl or optionally substituted heteroaryl. That is, the anthracene compound represented by formula (3-H2) has at least three substituents selected from the group consisting of optionally substituted aryl and optionally substituted heteroaryl bonded to the anthracene ring. It is preferable to have such a structure.

In the anthracene compound represented by formula (3-H2), two of Ar ¹¹ to Ar ¹⁸ are optionally substituted aryl or optionally substituted heteroaryl, and the other six are hydrogen and unsubstituted. More preferably, they are optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, or optionally substituted alkoxy. That is, the anthracene compound represented by formula (3-H2) has three substituents selected from the group consisting of optionally substituted aryl and optionally substituted heteroaryl bonded to an anthracene ring. It is more preferable to have a structure.

In the anthracene compound represented by formula (3-H2), any two of Ar ¹¹ to Ar ¹⁸ are optionally substituted aryl or optionally substituted heteroaryl, and the other six are hydrogen, methyl , or t-butyl is more preferred.

Furthermore, in formula (3-H2), it is preferable that R ^c is hydrogen and any six of Ar ¹¹ to Ar ¹⁸ are hydrogen.

The anthracene compound represented by the formula (3-H2) is represented by the following formula (3-H2-A), (3-H2-B), (3-H2-C), (3-H2-D), or (3 -H2-E) is preferably an anthracene compound.

In formula (3-H2-A), (3-H2-B), (3-H2-C), (3-H2-D) or (3-H2-E), Ar ^c ', Ar ¹¹ ', Ar ¹² ', Ar ¹³ ', Ar ¹⁴ ', Ar ¹⁵ ', Ar ¹⁷ ', and Ar ¹⁸ ' are each independently phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl , chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A), and at least one hydrogen in these groups is phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzoflu It may be substituted with olenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A). Here, when both methylene hydrogens in fluorenyl and benzofluorenyl are substituted with phenyl, these phenyls may be bonded to each other through a single bond. ^{Methyl or _ _ _ _ _ _} t-Butyl may be attached.

Ar ^c ′, Ar ^{11 ′} , Ar ¹² ′, Ar ^{13 ′} , Ar ^{14 ′} , Ar ¹⁵ ′, Ar ¹⁷ ′, and Ar ¹⁸ ′ are each substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl When, it is preferably a group represented by any one of the above formulas (3-H2-X1) to (3-H2-X7).

Ar ^c ′, Ar ^{11 ′} , Ar ^{12 ′} , Ar ¹³ ′, Ar ¹⁴ ′, Ar ¹⁵ ′, Ar ¹⁷ ′, and Ar ¹⁸ ′ are each independently phenyl, biphenylyl (especially biphenyl-2-yl or biphenyl -4-yl), terphenyl (especially m-terphenyl-5'-yl), naphthyl, phenanthryl, fluorenyl, or any of the above formulas (A-1) to (A-4). In this case, at least one hydrogen in these groups is phenyl, biphenylyl, naphthyl, phenanthryl, fluorenyl, or one of the above formulas (A-1) to (A-4). It may be substituted with a group represented by any of the following.

Furthermore, at least One hydrogen may be substituted with halogen, cyano, or deuterium. Further, a deuterated form is preferable, and a form in which all anthracene rings are deuterated, or a form in which all hydrogen atoms are deuterated is preferable.

Particularly preferred examples of the anthracene compound represented by the formula (3-H2) include anthracene compounds represented by the following formula (3-H2-Aa).

In formula (3-H2-Aa), Ar ^c ', Ar ¹⁴ ', and Ar ¹⁵ ' each independently represent phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl. , or a group represented by any of the above formulas (A-1) to (A-11), and at least one hydrogen in these groups is phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, benzo. It may be substituted with fluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by any one of formulas (A-1) to (A-11). Here, when both methylene hydrogens in fluorenyl and benzofluorenyl are substituted with phenyl, these phenyls may be bonded to each other through a single bond. Further, carbon atoms on the anthracene ring to which Ar ^c ′, Ar ¹⁴ ′, and Ar ¹⁵ ′ are not bonded may be substituted with methyl or t-butyl instead of hydrogen. At least one hydrogen in the compound represented by formula (3-H2-Aa) may be substituted with halogen or cyano, and at least one hydrogen in the compound represented by formula (3-H2-Aa) is Substituted with deuterium.

In formula (3-H2-Aa), Ar ^c ', Ar ¹⁴ ', and Ar ¹⁵ ' are each independently phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, or the above formulas (A-1) to ( A-4) is preferable, and at least one hydrogen in these groups is phenyl, naphthyl, phenanthryl, fluorenyl, or a group represented by formulas (A-1) to (A-4). It may be substituted with a group represented by any of the following.

In the compound represented by the formula (3-H2-Aa), at least the hydrogen bonded to the 10th carbon of the anthracene ring (the carbon to which Ar ^c ' is bonded is the 9th position) is substituted with deuterium. Preferably. That is, the compound represented by the formula (3-H2-Aa) is preferably a compound represented by the following formula (3-H2-Ab). In addition, in formula (3-H2-Ab), D is deuterium, and Ar ^c ′, Ar ¹⁴ ′, and Ar ¹⁵ ′ are the same as defined in formula (3-H2-Aa). D in formula (3-H2-Ab) indicates that at least this position is deuterium, and any one or more of the other hydrogens in formula (3-H2-Ab) may be deuterium at the same time. It is also preferable that all hydrogens in formula (3-H2-Ab) are deuterium.

Further, as specific examples of anthracene compounds, for example, compounds represented by formulas (3-131-Y) to (3-182-Y), formula (3-183-N), formula (3- 184-Y) to formula (3-284-Y), and formula (3-500) to formula (3-557), and formula (3-600) to formula (3-605), and formula (3-606 -Y) to compounds represented by the formula (3-626-Y). Although the hydrogen atoms in these formulas may be partially or completely substituted with deuterium, particularly preferred forms of deuterium substitution are listed individually. Y in the formula is -O-, -S-, >NR ²⁹ (R ²⁹ has the same definition as above) or >C(-R ³⁰ ) ₂ (R ³⁰ is an optionally connected aryl or alkyl ), R ²⁹ is, for example, phenyl, and R ³⁰ is, for example, methyl. For example, when Y is O, formula (3-131-Y) becomes formula (3-131-O), and when Y is -S- or >N-R ²⁹ , formula (3-131-Y) becomes formula (3-131-O). 131-S) or formula (3-131-N).

上記式中、Ｄは重水素である。

In the above formula, D is deuterium.

Among these compounds, formula (3-131-Y) to formula (3-134-Y), formula (3-138-Y), formula (3-140-Y) to formula (3-143-Y) , formula (3-150-Y), formula (3-153-Y) to formula (3-156-Y), formula (3-166-Y), formula (3-168-Y), formula (3- 173-Y), formula (3-177-Y), formula (3-180-Y) to formula (3-183-N), formula (3-185-Y), formula (3-190-Y), Formula (3-223-Y), Formula (3-241-Y), Formula (3-250-Y), Formula (3-252-Y) to Formula (3-254-Y), Formula (3-270 -Y) ~ Formula (3-284-Y), Formula (3-501), Formula (3-507), Formula (3-508), Formula (3-509), Formula (3-513), Formula ( 3-514), formula (3-519), formula (3-521), formula (3-538) to formula (3-547) or formula (3-600) to formula (3-605), and formula ( Compounds represented by formulas (3-606-Y) to (3-626-Y) are preferred. Moreover, Y is preferably -O- or >NR ²⁹ , more preferably -O-. Also preferred is a form of deuterium substitution.

The above-mentioned anthracene compounds include a compound having a reactive group at a desired position of the anthracene skeleton, and a moiety such as X, Ar ⁴ and the structure of formula (A) in the case of an anthracene compound represented by formula (3-H). It can be produced by applying Suzuki coupling, Negishi coupling, and other known coupling reactions using a compound having a reactive group in its structure as a starting material. Examples of the reactive group of these reactive compounds include halogen and boronic acid. As a specific manufacturing method, for example, the synthesis method in paragraphs [0089] to [0175] of International Publication No. 2014/141725 can be referred to.

<Fluorene compound>
The compound represented by formula (4-H) basically functions as a host.

In formula (4-H),
R ¹ to R ¹⁰ each independently represent hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the fluorene skeleton in formula (4-H) via a linking group), diarylamino, diaryl, R ¹ and R ² , R ² and R ³ , R ³ and R ⁴ , R ⁵ and R ⁶ , R ⁶ and R ⁷ , R ⁷ and R ⁸ or R ⁹ and R ¹⁰ are each independently bonded to form a fused ring. Alternatively, a spiro ring may be formed, and at least one hydrogen in the formed ring is aryl, heteroaryl (the heteroaryl may be bonded to the formed ring via a linking group), diaryl. optionally substituted with amino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, in which at least one hydrogen is substituted with aryl, heteroaryl, alkyl or cycloalkyl; At least one hydrogen in the compound represented by formula (4-H) may be substituted with halogen, cyano or deuterium.

For details of each group in the definition of formula (4-H), the above explanation regarding the polycyclic aromatic compound of formula (1) can be cited.

Examples of alkenyl in R ¹ to R ¹⁰ include alkenyl having 2 to 30 carbon atoms, preferably alkenyl having 2 to 20 carbon atoms, more preferably alkenyl having 2 to 10 carbon atoms, and alkenyl having 2 to 6 carbon atoms. Alkenyl is more preferred, and alkenyl having 2 to 4 carbon atoms is particularly preferred. Preferred alkenyls are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

In addition, as a specific example of heteroaryl, any one from the following formula (4-Ar1), formula (4-Ar2), formula (4-Ar3), formula (4-Ar4) or formula (4-Ar5) Also included are monovalent groups represented by excluding one hydrogen atom.

In the formulas (4-Ar1) to (4-Ar5), Y ¹ is each independently O, S or NR, R is phenyl, biphenylyl, naphthyl, anthracenyl or hydrogen, and the formula ( At least one hydrogen in the structures of formulas (4-Ar1) to (4-Ar5) may be substituted with phenyl, biphenylyl, naphthyl, anthracenyl, phenanthrenyl, methyl, ethyl, propyl, or butyl.

These heteroaryls may be bonded to the fluorene skeleton in formula (4-H) via a linking group. That is, the fluorene skeleton in formula (4-H) and the above-mentioned heteroaryl may not only be directly bonded, but also be bonded through a linking group between them. Examples of the linking group include phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH ₂ CH ₂ -, -CH ₂ CH ₂ O-, or -OCH ₂ CH ₂ O-.

Furthermore, R ¹ and R ² , R ² and R ³ , R ³ and R ⁴ , R ⁵ and R ⁶ , R ⁶ and R ⁷ , or R ⁷ and R ⁸ in formula (4-H) are each independently R 9 and R 10 may combine to form a fused ring, or R ⁹ and R ¹⁰ may combine to form a spiro ring. The condensed ring formed by R ¹ to R ⁸ is a ring condensed to the benzene ring in formula (4-H), and is an aliphatic ring or an aromatic ring. Preferably, it is an aromatic ring, and examples of the structure including a benzene ring in formula (4-H) include a naphthalene ring and a phenanthrene ring. The spiro ring formed by R ⁹ and R ¹⁰ is a ring spiro-bonded to the 5-membered ring in formula (4-H), and is an aliphatic ring or an aromatic ring. Preferably it is an aromatic ring, such as a fluorene ring.

The compound represented by the formula (4-H) is preferably a compound represented by the following formula (4-H-1), formula (4-H-2) or formula (4-H-3). , a compound in which a benzene ring formed by combining R ¹ and R ² in formula (4-H) is fused, and a benzene ring formed by combining R ³ and R ⁴ in formula (4-H), respectively. is a compound in which R ¹ to R ⁸ are not bonded in formula (4-H).

The definitions of R 1 to R 10 in formula (4-H-1), formula (4-H-2), and formula (4-H-3) are the same as the corresponding R ¹ to R ¹⁰ in formula ( ^{4 -} H). The definitions of R ¹¹ to R ¹⁴ in formula (4-H-1) and formula (4-H-2) are also the same as R ¹ to R ¹⁰ in formula (4-H).

The compound represented by the formula (4-H) is more preferably a compound represented by the following formula (4-H-1A), formula (4-H-2A) or formula (4-H-3A). A compound in which R ⁹ and R ¹⁰ are combined to form a spiro-fluorene ring in formula (4-H-1), formula (4-H-1), or formula (4-H-3), respectively. be.

The definitions of R ² to R ⁷ in formula (4-H-1A), formula (4-H-2A) and formula (4-H-3A) are formula (4-1), formula (4-2) and formula It is the same as the corresponding R ² to R ⁷ in (4-3), and the definitions of R ¹¹ to R ¹⁴ in formula (4-H-1A) and formula (4-H-2A) are also the same as formula (4-1). and R ¹¹ to R ¹⁴ in formula (4-2).

Furthermore, all or part of hydrogen in the compound represented by formula (4-H) may be substituted with halogen, cyano, or deuterium.

More specific examples of the fluorene compound as the host of the present invention include compounds represented by the following structural formula. Note that "Me" represents methyl.

<Dibenzochrysene compound>
The dibenzochrysene compound as a host is, for example, a compound represented by the following formula (5-H).

In formula (5-H), R ¹ to R ¹⁶ are each independently hydrogen, aryl, or heteroaryl (the heteroaryl is bonded to the dibenzochrysene skeleton in formula (5-H) via a linking group). ), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, in which at least one hydrogen is substituted with aryl, heteroaryl, alkyl or cycloalkyl. Also, adjacent groups among R ¹ to R ¹⁶ may be bonded to each other to form a condensed ring, and at least one hydrogen in the formed ring is aryl, heteroaryl (the heteroaryl) aryl may be bonded to the formed ring via a linking group), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy; At least one hydrogen in these may be substituted with aryl, heteroaryl, alkyl or cycloalkyl, and at least one hydrogen in the compound represented by formula (5-H) may be substituted with halogen, cyano or deuterium. may be replaced with .

For details of each group in the definition of formula (5-H), the above explanation regarding the polycyclic aromatic compound of formula (1) can be cited.

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

Specific examples of heteroaryl include any one of the compounds of the following formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4), or formula (5-Ar5). Also included are monovalent groups represented by excluding one hydrogen atom.

In the formulas (5-Ar1) to (5-Ar5), Y ¹ is each independently O, S or NR, R is phenyl, biphenylyl, naphthyl, anthracenyl or hydrogen, and the formula ( At least one hydrogen in the structures of formulas (5-Ar1) to (5-Ar5) may be substituted with phenyl, biphenylyl, naphthyl, anthracenyl, phenanthrenyl, methyl, ethyl, propyl, or butyl.

These heteroaryls may be bonded to the dibenzochrysene skeleton in formula (5-H) via a linking group. That is, the dibenzochrysene skeleton in formula (5-H) and the above-mentioned heteroaryl may not only be directly bonded, but also may be bonded through a linking group between them. Examples of the linking group include phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH ₂ CH ₂ -, -CH ₂ CH ₂ O-, or -OCH ₂ CH ₂ O-.

In the compound represented by formula (5-H), R ¹ , R ⁴ , R ⁵ , R ⁸ , R ⁹ , R ¹² , R ¹³ and R ¹⁶ are preferably hydrogen. In this case, R ² , R ³ , R ⁶ , R ⁷ , R ¹⁰ , R ¹¹ , R ¹⁴ and R ¹⁵ in formula (5-H) are each independently hydrogen, phenyl, biphenylyl, naphthyl, anthracenyl. , phenanthrenyl, a monovalent group having the structure of formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5) (having the structure _{A monovalent} group is _a group of _{the formula (} 5- (which may be bonded to the dibenzochrysene skeleton in H), methyl, ethyl, propyl, or butyl is preferable.

The compound represented by formula (5-H) more preferably has R ¹ , R ² , R ⁴ , R ⁵ , R ⁷ , R 8 , R ⁹ , R ¹⁰ , R ¹² , R ¹³ , R ^{15 and} R ¹⁶ is hydrogen. In this case, at least one (preferably one or two, more preferably one) of R ³ , R ⁶ , R ¹¹ and R ¹⁴ in formula (5-H) is a single bond, phenylene, biphenylene, Naphthylene, anthracenylene, methylene, ethylene, -OCH ₂ CH ₂ -, -CH ₂ CH ₂ O-, or -OCH ₂ CH ₂ O-, formula (5-Ar1), formula (5-Ar2), A monovalent group having the structure of formula (5-Ar3), formula (5-Ar4), or formula (5-Ar5), and substituted with a monovalent group other than at least one of the above (that is, a monovalent group having the above structure) (other than position) is hydrogen, phenyl, biphenylyl, naphthyl, anthracenyl, methyl, ethyl, propyl, or butyl, and at least one hydrogen in these is phenyl, biphenylyl, naphthyl, anthracenyl, methyl, ethyl, propyl, or May be substituted with butyl.

Furthermore, R ² , R ³ , R ⁶ , R ⁷ , R ¹⁰ , R ¹¹ , R ¹⁴ and R ¹⁵ in formula (5-H) are represented by formula (5-Ar1) to formula (5-Ar5). When a monovalent group having a structure is selected, at least one hydrogen in the structure is bonded to any one of R ¹ to R ¹⁶ in formula (5-H) to form a single bond. It's okay.

More specific examples of the dibenzochrysene compound as a host of the present invention include compounds represented by the following structural formula.

The above-mentioned materials for the light-emitting layer (host material and dopant material) are polymeric compounds obtained by polymerizing reactive compounds substituted with reactive substituents as monomers, or crosslinked polymers thereof, or main chains thereof. A pendant type polymer compound obtained by reacting a type polymer with the above-mentioned reactive compound, or a pendant type polymer crosslinked product thereof can also be used as a material for a light emitting layer. As for the reactive substituent in this case, the explanation for the polycyclic aromatic compound represented by formula (1) can be cited.

<Light-emitting layer containing assisting dopant and emitting dopant>
The light emitting layer in the organic electroluminescent device may include a host compound as a first component, an assisting dopant (compound) as a second component, and an emitting dopant (compound) as a third component. In this embodiment, the polycyclic aromatic compound of the present invention is preferably used as an emitting dopant. A thermally activated delayed phosphor can be used as the assisting dopant (compound).

In the following description, an organic electroluminescent device using a thermally activated delayed phosphor as an assisting dopant may be referred to as a "TADF device" (TADF Assisting Fluorescence device). The "host compound" in a TAF element is a compound whose lowest excited singlet energy level determined from the shoulder on the short wavelength side of the peak of the fluorescence spectrum is a thermally activated delayed phosphor as a second component and a thermally activated delayed phosphor as a third component. It means a compound that is higher than the emitting dopant.

A "thermally activated delayed phosphor" absorbs thermal energy to cause reverse intersystem crossing from the lowest excited triplet state to the lowest excited singlet state, and then radiatively deactivates from the lowest excited singlet state to cause a delay. A compound that can emit fluorescence. However, "thermally activated delayed fluorescence" also includes fluorescence that passes through a higher-order triplet during the excitation process from the lowest excited triplet state to the lowest excited singlet state. For example, a paper by Monkman et al. of Durham University (NATURE COMMUNICATIONS,7:13680,DOI: 10.1038/ncomms13680), a paper by Hosokai et al. of the National Institute of Advanced Industrial Science and Technology (Hosokai et al., Sci. Adv. 2017;3: e1603282), Kyoto A paper by Sato et al. from University (Scientific Reports, 7:4820, DOI:10.1038/s41598-017-05007-7) and an academic conference presentation by Sato et al. from Kyoto University (98th Spring Annual Meeting of the Chemical Society of Japan, presentation number: 2I4- 15, Mechanism of highly efficient light emission in organic electroluminescence using DABNA as a light-emitting molecule (Graduate School of Engineering, Kyoto University). In the present invention, when the fluorescence lifetime of a sample containing the target compound is measured at 300 K, the target compound is determined to be a "thermally activated delayed phosphor" based on the observation of a slow fluorescence component. Here, the slow fluorescence component refers to one whose fluorescence lifetime is 0.1 μsec or more. The fluorescence lifetime can be measured using, for example, a fluorescence lifetime measuring device (manufactured by Hamamatsu Photonics, C11367-01).

The polycyclic aromatic compound of the present invention can function as an emitting dopant, and the "thermally activated delayed phosphor" can function as an assisting dopant that assists the polycyclic aromatic compound of the present invention to emit light. Can be done.

FIG. 2 shows an energy level diagram of a light emitting layer of a TAF element using a general fluorescent dopant as an emitting dopant (ED). In the figure, the ground state energy level of the host is E(1,G), the lowest excited singlet energy level determined from the shoulder on the short wavelength side of the fluorescence spectrum of the host is E(1,S,Sh), and the host The lowest excited triplet energy level determined from the shoulder on the short wavelength side of the phosphorescent spectrum is E(1, T, Sh), and the energy level of the ground state of the assisting dopant, which is the second component, is E(2, G), the lowest excited singlet energy level determined from the shoulder on the short wavelength side of the fluorescence spectrum of the assisting dopant, which is the second component, is E(2,S,Sh), and the phosphorus of the assisting dopant, which is the second component. The lowest excited triplet energy level determined from the shoulder on the short wavelength side of the optical spectrum is E(2,T,Sh), and the ground state energy level of the third component, the emitting dopant, is E(3,G). , the lowest excited singlet energy level determined from the shoulder on the short wavelength side of the fluorescence spectrum of the third component, the emitting dopant, is E(3,S,Sh), and the phosphorescence spectrum of the third component, the emitting dopant. Let E (3, T, Sh) be the lowest excited triplet energy level found from the shoulder on the short wavelength side of . In a TAF element, when a general fluorescent dopant is used as an emitting dopant (ED), the energy upconverted by the assisting dopant is at the lowest excited singlet energy level E (3, S, Sh) of the emitting dopant. and emits light. However, some of the lowest excited triplet energy E(2,T,Sh) on the assisting dopant moves to the lowest excited triplet energy level E(3,T,Sh) of the emitting dopant, and An intersystem crossing occurs on the dopant from the lowest excited singlet energy level E(3,S,Sh) to the lowest excited triplet energy level E(3,T,Sh), followed by the ground state E(3, G) is thermally inactivated. Due to this path, some energy is not used for light emission, resulting in wasted energy.

In contrast, in the organic electroluminescent device of this embodiment, the energy transferred from the assisting dopant to the emitting dopant can be efficiently used for light emission, thereby achieving high luminous efficiency. This is presumed to be due to the following light emission mechanism.

A preferable energy relationship in the organic electroluminescent device of this embodiment is shown in FIG. In the organic electroluminescent device of this embodiment, the compound having a boron atom as an emitting dopant has a high lowest excited triplet energy level E (3, T, Sh). Therefore, even if the excited singlet energy upconverted by the assisting dopant intersystem-crosses to the lowest excited triplet energy level E (3, T, Sh) in the emitting dopant, the or recovered to the lowest excited triplet energy level E (2, T, Sh) on the assisting dopant (thermally activated delayed phosphor). Therefore, the generated excitation energy can be used for light emission without wasting it. It is also expected that by separating the upconversion and luminescence functions into two types of molecules, each with its own strengths, the residence time of high energy will be reduced and the burden on the compound will be reduced.

In this embodiment, known host compounds can be used, such as compounds having at least one of a carbazole ring and a furan ring, and among them, at least one of furanyl and carbazolyl, and arylene and heteroarylene. It is preferable to use a compound bound to at least one of the following. Specific examples include mCP and mCBP.

The lowest excited triplet energy level E (1, T, Sh), which is determined from the shoulder on the short wavelength side of the peak of the phosphorescence spectrum of the host compound, is the lowest excited triplet energy level E (1, T, Sh), which is determined from the shoulder on the short wavelength side of the peak of the phosphorescence spectrum of the host compound. Higher than the lowest excited triplet energy level E (2, T, Sh), E (3, T, Sh) of the emitting dopant or assisting dopant that has the highest lowest excited triplet energy level in the layer. More preferably, the lowest excited triplet energy level E(1,T,Sh) of the host compound is 0 compared to E(2,T,Sh) and E(3,T,Sh). It is preferably .01 eV or more, more preferably 0.03 eV or more, and even more preferably 0.1 eV or more. Further, a TADF-active compound may be used as the host compound.

As the host compound, for example, a compound represented by any one of the above formulas (H1), (H2), and (H3) can be used.

<Thermally activated delayed phosphor (assisting dopant)>
The thermally activated delayed phosphor (TADF compound) used in TAF elements uses an electron-donating substituent called a donor and an electron-accepting substituent called an acceptor to combine intramolecular HOMO (Highest Occupied Molecular Orbital) and LUMO. A donor-acceptor thermally activated delayed phosphor (DA-type TADF compound) designed to localize the Lowest Unoccupied Molecular Orbital and cause efficient reverse intersystem crossing. ) is preferable. Here, in this specification, the term "electron-donating substituent" (donor) means a substituent and a partial structure in which a HOMO orbital is localized in a thermally activated delayed phosphor molecule; The term "acceptor" means a substituent and a partial structure in which a LUMO orbital is localized in a thermally activated delayed phosphor molecule.

In general, thermally activated delayed phosphors using donors and acceptors have large spin-orbit coupling (SOC) due to their structure and small exchange interaction between HOMO and LUMO, ΔE (ST ) is small, resulting in very fast inverse intersystem crossing speeds. On the other hand, thermally activated delayed fluorophores that use donors and acceptors have a large structural relaxation in the excited state (for some molecules, the stable structure is different between the ground state and the excited state, so external stimuli can cause the structure to be excited from the ground state). When the conversion occurs, the structure changes to a stable structure in the excited state), giving a broad emission spectrum, which may reduce color purity when used as a luminescent material.

As a thermally activated delayed phosphor in a TAF element, for example, a compound in which a donor and an acceptor are bonded directly or via a spacer can be used. Examples of the electron donating group (donor structure) and electron accepting group (acceptor structure) used in the thermally activated delayed phosphor of the present invention include those described in Chemistry of Materials, 2017, 29, 1946-1963. The structures described can be used. Donor structures include carbazole, dimethylcarbazole, di-tert-butylcarbazole, dimethoxycarbazole, tetramethylcarbazole, benzofluorocarbazole, benzothienocarbazole, phenyldihydroindolocarbazole, phenylbicarbazole, bicarbazole, tercarbazole, Diphenylcarbazolylamine, tetraphenylcarbazolyldiamine, phenoxazine, dihydrophenazine, phenothiazine, dimethyldihydroacridine, diphenylamine, bis(tert-butylphenyl)amine, N1-(4-(diphenylamino)phenyl)-N4,N4 -diphenylbenzene-1,4-diamine, dimethyltetraphenyldihydroacridinediamine, tetramethyl-dihydroindenoacridine, and diphenyldihydrodibenzazacilline. Acceptor structures include sulfonyldibenzene, benzophenone, phenylenebis (phenylmethone), benzonitrile, isonicotinonitrile, phthalonitrile, isophthalonitrile, paraphthalonitrile, benzenetricarbonitrile, triazole, oxazole, thiadiazole. , benzothiazole, benzobis(thiazole), benzoxazole, benzobis(oxazole), quinoline, benzimidazole, dibenzoquinoxaline, heptaazaphenalene, thioxanthone dioxide, dimethylanthracenone, anthracenedione, 5H-cyclopenta[1,2-b :5,4-b']dipyridine, fluorene dicarbonitrile, triephenyltriazine, pyrazinedicarbonitrile, pyrimidine, phenylpyrimidine, methylpyrimidine, pyridinedicarbonitrile, dibenzoquinoxalinedicarbonitrile, bis(phenylsulfonyl)benzene, Mention may be made of dimethylthioxanthene dioxide, thianthrene tetraoxide and tris(dimethylphenyl)borane. In particular, compounds having thermally activated delayed fluorescence in TAF elements include carbazole, phenoxazine, acridine, triazine, pyrimidine, pyrazine, thioxanthene, benzonitrile, phthalonitrile, isophthalonitrile, diphenylsulfone, triazole, A compound having at least one selected from oxadiazole, thiadiazole and benzophenone is preferred.

The compound used as an assisting dopant in the emitting layer of the TAF element is preferably a thermally activated delayed phosphor, and the emission spectrum thereof at least partially overlaps with the absorption peak of the emitting dopant. In the following, compounds that can be used as assisting dopants (thermally activated delayed phosphors) in the light emitting layer of TAF elements will be exemplified. However, the compound that can be used as a thermally activated delayed phosphor in a TAF element is not limited to the following exemplified compounds. In the formula below, the wavy line represents the bonding position.

Furthermore, a compound represented by any one of the following formulas (AD1), (AD2) and (AD3) can also be used as a thermally activated delayed phosphor.

In the above formulas (AD1), (AD2) and (AD3), M is each independently a single bond, -O-, >N-Ar or >CAr ₂ , and the depth of the HOMO of the formed substructure From the viewpoint of the height of the lowest excited singlet energy level and the lowest excited triplet energy level, it is preferably a single bond, -O- or >N-Ar. J is a spacer structure that separates the donor partial structure and the acceptor partial structure, each of which is an arylene having 6 to 18 carbon atoms, and the conjugate that oozes from the donor partial structure and acceptor partial structure. From the viewpoint of size, arylene having 6 to 12 carbon atoms is preferred. More specific examples include phenylene, methylphenylene and dimethylphenylene. Q is each independently =C(-H)- or =N-, and is the shallowness of the LUMO of the substructure to be formed and the height of the lowest excited singlet energy level and the lowest excited triplet energy level From this point of view, preferably =N-. Ar is each independently hydrogen, an aryl having 6 to 24 carbon atoms, a heteroaryl having 2 to 24 carbon atoms, an alkyl having 1 to 12 carbon atoms, or a cycloalkyl having 3 to 18 carbon atoms; From the viewpoint of the HOMO depth and the height of the lowest excited singlet energy level and the lowest excited triplet energy level, hydrogen, an aryl having 6 to 12 carbon atoms, a heteroaryl having 2 to 14 carbon atoms, Alkyl having 1 to 4 carbon atoms or cycloalkyl having 6 to 10 carbon atoms, more preferably hydrogen, phenyl, tolyl, xylyl, mesityl, biphenyl, pyridyl, bipyridyl, triazinyl, carbazolyl, dimethylcarbazolyl, di-tert -butylcarbazolyl, benzimidazole or phenylbenzimidazole, more preferably hydrogen, phenyl or carbazolyl. m is 1 or 2. n is an integer of (6-m) or less, and preferably an integer of 4 to (6-m) from the viewpoint of steric hindrance. Furthermore, at least one hydrogen in the compounds represented by the above formulas may be substituted with halogen or deuterium.

More specifically, the compounds used as the second component in this embodiment include 4CzBN, 4CzBN-Ph, 5CzBN, 3Cz2DPhCzBN, 4CzIPN, 2PXZ-TAZ, Cz-TRZ3, BDPCC-TPTA, MA-TA, PA-TA, FA-TA, PXZ-TRZ, DMAC-TRZ, BCzT, DCzTrz, DDCzTRz, spiroAC-TRZ, Ac-HPM, Ac-PPM, Ac-MPM, TCzTrz, TmCzTrz and DCzm Preferably it is CzTrz.

The compound used as the second component in this embodiment may be a donor-acceptor type TADF compound represented by DA in which one donor D and one acceptor A are bonded directly or via a linking group, but An organic electroluminescent device having a structure represented by the following formula (DAD1) in which a plurality of donors D are bonded to one acceptor A directly or through a linking group has better characteristics. It is preferable because it becomes a product.

(D ¹ -L ¹ )n-A ¹ (DAD1)

Formula (DAD1) includes a compound represented by the following formula (DAD2).

D ² -L ² -A ² -L ³ -D ³ (DAD2)

In formula (DAD1) and formula (DAD2), D ¹ , D ² and D ³ each independently represent a donor group. As the donor group, the above donor structure can be employed. A ¹ and A ² each independently represent an acceptor group. As the acceptor group, the above acceptor structure can be employed. L ¹ , L ² and L ³ each independently represent a single bond or a conjugated linking group. The conjugated linking group is a spacer structure that separates a donor group and an acceptor group, and is preferably an arylene having 6 to 18 carbon atoms, more preferably an arylene having 6 to 12 carbon atoms. More preferably, L ¹ , L ² and L ³ are each independently phenylene, methylphenylene or dimethylphenylene. In formula (DAD1), n represents an integer greater than or equal to 2 and less than or equal to the maximum number that can be replaced by A ¹ . For example, n may be selected within the range of 2 to 10, or may be selected within the range of 2 to 6. When n is 2, the compound is represented by the formula (DAD2). The n pieces of D ¹ may be the same or different, and the n pieces of L ¹ may be the same or different. Preferred specific examples of the compounds represented by formula (DAD1) and formula (DAD2) include 2PXZ-TAZ and the following compounds, but the second component that can be employed in the present invention is Not limited.

In this embodiment, the light-emitting layer may be a single layer or composed of multiple layers. Further, the host compound, the thermally activated delayed phosphor, and the polycyclic aromatic compound of the present invention may be contained in the same layer, or at least one component may be contained in each of multiple layers. The host compound, thermally activated delayed phosphor, and polycyclic aromatic compound of the present invention contained in the light-emitting layer may each be one type or a combination of a plurality of types. The assisting dopant and the emitting dopant may be wholly or partially contained in the host compound as a matrix. The light-emitting layer doped with an assisting dopant and an emitting dopant can be formed by forming a film using a ternary co-evaporation method using a host compound, an assisting dopant, and an emitting dopant, or by mixing a host compound, an assisting dopant, and an emitting dopant in advance. It can be formed by a wet film-forming method, which involves simultaneously depositing the host compound, assisting dopant, and emitting dopant in an organic solvent and applying a luminescent layer-forming composition (paint). can.

The amount of the host compound to be used varies depending on the type of the host compound, and may be determined depending on the characteristics of the host compound. The amount of the host compound to be used is preferably 40 to 99.999% by mass, more preferably 50 to 99.99% by mass, and even more preferably 60 to 99.9% by mass of the entire material for the light emitting layer. It is. The above range is preferable in terms of efficient charge transport and efficient energy transfer to the dopant, for example.

The amount of assisting dopant (thermally activated delayed phosphor) to be used varies depending on the type of assisting dopant, and may be determined according to the characteristics of the assisting dopant. The amount of assisting dopant to be used is preferably 1 to 60% by weight, more preferably 2 to 50% by weight, and even more preferably 5 to 30% by weight based on the entire material for the light emitting layer. The above range is preferable in that, for example, energy can be efficiently transferred to the emitting dopant.

The amount of the emitting dopant (a compound having a boron atom) to be used varies depending on the type of the emitting dopant, and may be determined depending on the characteristics of the emitting dopant. The amount of the emitting dopant to be used is preferably 0.001 to 30% by mass, more preferably 0.01 to 20% by mass, and even more preferably 0.1 to 10% by mass of the entire material for the emitting layer. %. The above range is preferable in that, for example, concentration quenching phenomenon can be prevented.

It is preferable that the amount of the emitting dopant to be used is low because concentration quenching phenomenon can be prevented. It is preferable that the assisting dopant be used in a high concentration from the viewpoint of efficiency of the thermally activated delayed fluorescence mechanism. Furthermore, from the viewpoint of the efficiency of the thermally activated delayed fluorescence mechanism of the assisting dopant, it is preferable that the amount of the emitting dopant used is lower than the amount of the assisting dopant used.

<2-1-3. Substrate in organic electroluminescent device>
The 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 into a plate shape, a film shape, or a sheet shape depending on the purpose. For example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, etc. are used. Among these, glass plates and plates made of transparent synthetic resins such as polyester, polymethacrylate, polycarbonate, and polysulfone are preferred. If it is a glass substrate, soda lime glass or non-alkali glass may be used, and the thickness may be sufficient to maintain mechanical strength, for example, 0.2 mm or more. The upper limit of the thickness is, for example, 2 mm or less, preferably 1 mm or less. As for the material of the glass, alkali-free glass is preferable because fewer ions elute from the glass, but soda lime glass coated with a barrier coating such as SiO ₂ is also commercially available, so it is recommended to use this. can. 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 of the substrate 101 in order to improve gas barrier properties. In particular, a synthetic resin plate, film, or sheet with low gas barrier properties may be used as the substrate 101. When used, it is preferable to provide a gas barrier film.

<2-1-4. Anode in organic electroluminescent device>
The anode 102 plays the role of injecting holes into the light emitting layer 105. Note that when either one of the hole injection layer 103 and the 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. .

Examples of materials 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, etc.). (IZO, etc.), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass, Nesa glass, etc. Examples of the organic compound include polythiophenes such as poly(3-methylthiophene), conductive polymers such as polypyrrole, and polyaniline. In addition, materials that are used as anodes for organic EL devices may be selected as appropriate.

The resistance of the transparent electrode is not limited as long as it can supply sufficient current for light emission of the light emitting element, but from the viewpoint of power consumption of the light emitting element, it is desirable that the resistance be low. For example, an ITO substrate with a resistance of 300 Ω/□ or less can function as an element electrode, but since it is now possible to supply substrates with a resistance of about 10 Ω/□, for example, 100 to 5 Ω/□, preferably 50 to 5 Ω. It is particularly desirable to use a low resistance product with /□. The thickness of ITO can be arbitrarily selected according to the resistance value, but it is usually used between 50 and 300 nm.

<2-1-5. Hole injection layer and hole transport layer in organic electroluminescent device>
The hole injection layer 103 plays a role of efficiently injecting holes moving from the anode 102 into the light emitting layer 105 or the hole transport 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 via 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 laminating and mixing one or more hole injection/transport materials, or by a mixture of a hole injection/transport material and a polymer binder. be done. The layer may also be formed by adding an inorganic salt such as iron(III) chloride to the hole injection/transport material.

As a hole injection/transport material, it is necessary to efficiently inject and transport holes from the positive electrode between the electrodes where an electric field is applied, and the material has high hole injection efficiency and efficiently transports the injected holes. It is desirable to do so. For this purpose, it is preferable to use a substance that has a low ionization potential, high hole mobility, excellent stability, and does not easily generate trapping impurities during production and use.

Materials for forming the hole injection layer 103 and the hole transport layer 104 include compounds conventionally used as hole charge transport materials in photoconductive materials, p-type semiconductors, and hole injection layers of organic EL devices. Any compound can be selected and used from among the known compounds used in 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 (4,4', 4”-tris(N-carbazolyl)triphenylamine, polymer with aromatic tertiary amino in main chain 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 , triphenylamine derivatives such as 4,4',4''-tris(3-methylphenyl(phenyl)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 (for example, 1,4,5,8,9,12-hexaazatriphenylene-2,3,6,7,10, 11-hexacarbonitrile, etc.), heterocyclic compounds such as porphyrin derivatives, and polysilanes. Polycarbonate, styrene derivatives, polyvinylcarbazole, polysilane, etc., which have the above-mentioned monomers in their side chains, are preferred as polymers, but they form the thin film necessary for producing light-emitting devices, allow holes to be injected from the anode, and further It is not particularly limited as long as it is a compound that can transport.

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 properties or a compound with good electron accepting properties. For doping with electron donating substances, strong electron acceptors such as tetracyanoquinone dimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinone dimethane (F4TCNQ) are known. (For example, the literature "M. Pfeiffer, A. Beyer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (22), 3202-3204 (1998)" and the literature "J. Blochwitz, M. Pfeiffer, T. Fritz, K. Leo, Appl. Phys. Lett., 73(6), 729-731 (1998)). These generate so-called holes by electron transfer processes in electron-donating base materials (hole-transporting materials). Depending on the number and mobility of holes, the conductivity of the base material varies considerably. As matrix materials having hole transport properties, for example benzidine derivatives (TPD etc.) or starburst amine derivatives (TDATA etc.) or certain metal phthalocyanines (in particular zinc phthalocyanine (ZnPc) etc.) are known ( JP 2005-167175A). The polycyclic aromatic compound of the present invention may be used as a material for forming a hole injection layer or a material for forming a hole transport layer.

<2-1-6. Electron blocking layer in organic electroluminescent device>
An electron blocking layer may be provided between the hole injection/transport layer and the light emitting layer to prevent diffusion of electrons from the light emitting layer. A compound represented by any of the above formulas (H1), (H2), and (H3) can be used to form the electron blocking layer. The polycyclic aromatic compound of the present invention may be used as a material for forming an electron blocking layer.

<2-1-7. Electron injection layer, 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 via the electron injection layer 107 to the light emitting layer 105. The electron transport layer 106 and the electron injection layer 107 are each formed by laminating 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 that is in charge of injecting electrons from the cathode and further transporting electrons, and it is desirable that the electron injection efficiency is high and that the injected electrons are efficiently transported. For this purpose, it is preferable that the material 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 role is to efficiently prevent holes from the anode from flowing to the cathode side without recombination, the electron transport capacity is not so great. Even if it is not high, it has the same effect of improving luminous efficiency as a material with high electron transport ability. Therefore, the electron injection/transport layer in this embodiment may also include the function of a layer that can efficiently block the movement of holes.

The material (electron transport material) forming the electron transport layer 106 or the electron injection layer 107 may be a compound conventionally used as an electron transport compound in photoconductive materials, or a compound used in the electron injection layer and electron transport layer of an organic EL device. Any known compound may be selected and used.

Materials used for the electron transport layer or electron injection layer include compounds consisting of an aromatic ring or a heteroaromatic ring composed of one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon, and phosphorus; It is preferable to contain at least one selected from pyrrole derivatives, fused ring derivatives thereof, and metal complexes having electron-accepting nitrogen. Specifically, fused ring aromatic ring derivatives such as naphthalene and anthracene, styryl aromatic ring derivatives represented by 4,4'-bis(diphenylethenyl)biphenyl, perinone derivatives, coumarin derivatives, and naphthalimide derivatives. , quinone derivatives such as anthraquinone and diphenoquinone, phosphine oxide derivatives, aryl nitrile 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 can be used alone or in combination with different materials.

Specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, fluoranthene derivatives, BO derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, and diphenylquinone derivatives. , perylene derivatives, 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, triazines 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-phenylbenzimidazol-2-yl)benzene, etc.), benzoxazole derivatives, thiazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives, terpyridine derivatives (1,3-bis(2, 2':6',2''-terpyridin-4'-yl)benzene, etc.), naphthyridine derivatives (bis(1-naphthyl)-4-(1,8-naphthyridin-2-yl)phenylphosphine oxide, etc.), aldazine Examples include derivatives, pyrimidine derivatives, aryl nitrile derivatives, indole derivatives, phosphine oxide derivatives, bisstyryl derivatives, silole derivatives and azoline derivatives.

Further, metal complexes having electron-accepting nitrogen can also be used, such as hydroxyazole complexes such as quinolinol metal complexes and hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. can give.

The above-mentioned materials can be used alone, but they can also be used in combination with different materials.

Among the above-mentioned materials, borane derivatives, pyridine derivatives, fluoranthene derivatives, BO derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, aryl nitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, quinolinol metals Preferred are complexes, thiazole derivatives, benzothiazole derivatives, silole derivatives and azoline derivatives.

The polycyclic aromatic compound of the present invention may be used as a material for forming an electron injection layer or a material for forming an electron transport layer.

The electron transport layer or the electron injection layer may further contain a substance that can reduce the material forming the electron transport layer or the electron injection layer. A variety of substances can be used as this reducing substance as long as it has a certain reducing property, such as alkali metals, alkaline earth metals, rare earth metals, alkali metal oxides, alkali metal halides, and alkali metals. 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 suitably used.

Preferred reducing substances include alkali metals such as Na (work function: 2.36 eV), K (work function: 2.28 eV), Rb (work function: 2.16 eV), or Cs (work function: 1.95 eV), and Ca (work function: 2.3 eV). Examples include alkaline earth metals such as Sr (2.0 to 2.5 eV), Sr (2.0 to 2.5 eV), and Ba (2.52 eV), and substances with a work function of 2.9 eV or less are particularly preferred. Among these, more preferable reducing substances are alkali metals such as K, Rb, or Cs, still more preferably Rb or Cs, and most preferable is Cs. These alkali metals have particularly high reducing ability, and by adding a relatively small amount to the material forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the life of the organic EL element can be extended. Further, as a reducing substance with a work function of 2.9 eV or less, a combination of two or more of these alkali metals is also preferable, and in particular, 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 including Cs, the reducing ability can be efficiently exhibited, and by adding it to the material forming the electron transport layer or the electron injection layer, the luminance of light emission and the longevity of the organic EL element can be improved.

<2-1-8. 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 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 forming the anode 102 can be used. Among them, metals such as tin, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium, and magnesium, or their alloys (magnesium-silver alloy, magnesium - indium alloys, aluminum-lithium alloys such as lithium fluoride/aluminum), etc.) are preferred. In order to increase electron injection efficiency and improve device characteristics, lithium, sodium, potassium, cesium, calcium, magnesium, or alloys containing these low work function metals are effective. However, these low work function metals are generally unstable in the atmosphere. In order to improve this point, a method is known in which, for example, the organic layer is doped with a trace amount of lithium, cesium, or magnesium to use a highly stable electrode. Other dopants that can also be used are inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide, and cesium oxide. However, it is not limited to these.

Additionally, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, or alloys of these metals, as well as inorganic materials such as silica, titania and silicon nitride, polyvinyl alcohol, and vinyl chloride, are used to protect the electrodes. A preferred example is to laminate a hydrocarbon polymer compound or the like. The method for producing these electrodes is not particularly limited as long as conduction can be achieved, such as resistance heating, electron beam evaporation, sputtering, ion plating, and coating.

<2-1-9. Binder that may be used in each layer>
The above materials used for the hole injection layer, hole transport layer, light emitting layer, electron transport layer and electron injection layer can be used alone to form each layer, but polyvinyl chloride, polycarbonate, Polystyrene, poly(N-vinylcarbazole), polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, vinyl acetate resin, ABS resin, polyurethane resin It can also be used by dispersing it in solvent-soluble resins such as phenol resins, xylene resins, petroleum resins, urea resins, melamine resins, unsaturated polyester resins, alkyd resins, epoxy resins, and curable resins such as silicone resins. be.

<2-1-10. Method for manufacturing organic electroluminescent device>
Each layer constituting an organic EL element is prepared by using a vapor deposition method, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination method, printing method, inkjet method, spin coating method or casting method, coating method, etc. It can be formed by forming a thin film using a method. The thickness of each layer formed in this way is not particularly limited and can be set appropriately depending on the properties of the material, but is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured using a crystal oscillation type film thickness measuring device. When forming a thin film using an evaporation method, the evaporation conditions vary depending on the type of material, the intended crystal structure and association structure of the film, and so on. Generally, the deposition conditions are: boat heating temperature +50 to +400°C, vacuum degree 10 ^-6 to 10 ^-3 Pa, deposition rate 0.01 to 50 nm/sec, substrate temperature -150 to +300°C, and film thickness 2 nm to 5 μm. It is preferable to set it appropriately within a range.

Next, as an example of a method for producing an organic EL device, an organic EL device consisting of an anode/hole injection layer/hole transport layer/light emitting layer made of a host material and dopant material/electron transport layer/electron injection layer/cathode will be described. The manufacturing method will be explained. After a thin film of an anode material is formed on a suitable substrate by vapor deposition or the like to produce an anode, thin films of a hole injection layer and a hole transport layer are formed on this anode. On top of this, a host material and a dopant material are co-deposited to form a thin film to form a light-emitting layer, an electron transport layer and an electron injection layer are formed on this light-emitting layer, and a thin film of a cathode material is further formed by vapor deposition or the like. By forming it and using it as a cathode, the desired organic EL element can be obtained. In addition, in the production of the above-mentioned organic EL element, it is also possible to reverse the production order and produce the cathode, electron injection layer, electron transport layer, light emitting layer, hole transport layer, hole injection layer, and anode in this order. It is.

When applying a direct current voltage to the organic EL element obtained in this way, it is sufficient to apply it with the anode as + polarity and the cathode as - polarity. Luminescence can be observed from the sides (anode or cathode, or both). This organic EL element also emits light when pulsed current or alternating current is applied. Note that the waveform of the applied alternating current may be arbitrary.

<2-1-11. Application examples of organic electroluminescent devices>
Organic EL elements can also be applied to display devices, lighting devices, and the like.
A display device or a lighting device equipped with an organic EL element can be manufactured by a known method such as connecting an organic EL element and a known drive device, and by using a known drive method such as DC drive, pulse drive, or AC drive. It can be driven by using it as appropriate.

Examples of display devices include panel displays such as color flat panel displays, flexible displays such as flexible color organic electroluminescent (EL) displays, etc. (Refer to Japanese Patent Publication No. 2004-281086, etc.). Furthermore, examples of the display method include one of a matrix method and a segment method. Note that matrix display and segment display may coexist in the same panel.

In a matrix, display pixels are arranged two-dimensionally in a grid or mosaic pattern, and characters or images are displayed as a collection of pixels. The shape and size of pixels are determined by the application. For example, rectangular pixels with sides of 300 μm or less are usually used to display images and characters on computers, monitors, and televisions, and in the case of large displays such as display panels, pixels with sides of mm order are used. become. In the case of monochrome display, pixels of the same color may be arranged, but in the case of color display, red, green, and blue pixels are displayed side by side. In this case, there are typically delta types and striped types. As a driving method for this matrix, either a line sequential driving method or an active matrix driving method may be used. Line sequential driving has the advantage of a simpler structure, but when considering operating characteristics, active matrix driving may be superior in some cases, so it is necessary to use it properly depending on the application.

In the segment method (type), a pattern is formed to display predetermined information, and a predetermined area is caused to emit light. Examples include time and temperature displays on digital clocks and thermometers, operating status displays on audio equipment and electromagnetic cookers, and panel displays on automobiles.

Examples of lighting devices include lighting devices for indoor lighting, backlights for liquid crystal display devices, etc. 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, watches, audio devices, automobile panels, display boards, signs, and the like. In particular, organic EL elements are being used as backlights for liquid crystal display devices, especially for personal computers, where thinning is an issue, considering that conventional methods consist of fluorescent lamps and light guide plates, making it difficult to make them thinner. Backlights using this type of backlight are thin and lightweight.

<2-2. Other organic devices＞
The polycyclic aromatic compound according to the present invention can be used in the production of organic field effect transistors, organic thin film solar cells, etc. in addition to the above-mentioned organic electroluminescent devices.

An organic field effect transistor is a transistor that controls current by an electric field generated by voltage input, and is provided with a gate electrode in addition to a source electrode and a drain electrode. When a voltage is applied to the gate electrode, an electric field is generated, and the flow of electrons (or holes) flowing between the source and drain electrodes can be arbitrarily blocked and the current can be controlled. Field-effect transistors are easier to miniaturize than simple transistors (bipolar transistors), and are often used as elements constituting integrated circuits and the like.

The structure of an organic field effect transistor is usually such that a source electrode and a drain electrode are provided in contact with an organic semiconductor active layer formed using the polycyclic aromatic compound according to the present invention, and a source electrode and a drain electrode are further provided in contact with the organic semiconductor active layer. A gate electrode may be provided with an insulating layer (dielectric layer) sandwiched therebetween. Examples of the device structure include the following structure.
(1) Substrate/gate electrode/insulator layer/source electrode/drain electrode/organic semiconductor active layer (2) substrate/gate electrode/insulator layer/organic semiconductor active layer/source electrode/drain electrode (3) substrate/organic Semiconductor active layer/source electrode/drain electrode/insulator layer/gate electrode (4) Substrate/source electrode/drain electrode/organic semiconductor active layer/insulator layer/gate electrode The organic field effect transistor configured in this way is It can be applied as a pixel drive switching element for active matrix drive type liquid crystal displays and organic electroluminescent displays.

An organic thin film solar cell has a structure in which an anode such as ITO, a hole transport layer, a photoelectric conversion layer, an electron transport layer, and a cathode are laminated on a transparent substrate such as glass. The photoelectric conversion layer has a p-type semiconductor layer on the anode side and an n-type semiconductor layer on the cathode side. The polycyclic aromatic compound according to the present invention can be used as a material for a hole transport layer, a p-type semiconductor layer, an n-type semiconductor layer, and an electron transport layer, depending on its physical properties. The polycyclic aromatic compound according to the present invention can function as a hole transport material or an electron transport material in an organic thin film solar cell. The organic thin film solar cell may appropriately include a hole blocking layer, an electron blocking layer, an electron injection layer, a hole injection layer, a smoothing layer, etc. in addition to the above. For the organic thin film solar cell, known materials used for organic thin film solar cells can be appropriately selected and used in combination.

<3. Wavelength conversion material＞
The polycyclic aromatic compound of the present invention can be used as a wavelength conversion material.
Currently, the application of multicolor technology using color conversion methods to liquid crystal displays, organic EL displays, lighting, etc. is being actively studied. Color conversion refers to converting the wavelength of light emitted from a light emitter into light with a longer wavelength, and represents, for example, converting ultraviolet light or blue light into green light or red light. By forming a wavelength conversion material having this color conversion function into a film and combining it with, for example, a blue light source, it becomes possible to extract the three primary colors of blue, green, and red from the blue light source, that is, to extract white light. By using a white light source that is a combination of such a blue light source and a wavelength conversion film having a color conversion function as a light source unit, and combining it with a liquid crystal driving part and a color filter, it is possible to produce a full-color display. In addition, if there is no liquid crystal drive part, it can be used as a white light source as it is, and can be applied as a white light source for, for example, LED lighting. Further, by using a blue organic EL element as a light source in combination with a wavelength conversion film that converts blue light into green light and red light, it becomes possible to produce a full-color organic EL display without using a metal mask. Furthermore, by using a blue micro-LED as a light source in combination with a wavelength conversion film that converts blue light into green light and red light, it becomes possible to produce a full-color micro-LED display at low cost.

The polycyclic aromatic compound of the present invention can be used as this wavelength conversion material. Using the wavelength conversion material containing the polycyclic aromatic compound of the present invention, light from a light source or light emitting element that generates ultraviolet light or shorter wavelength blue light can be converted into a display device (a display device using an organic EL element or a display device using an organic EL element). It can be converted into blue or green light with high color purity suitable for use in liquid crystal display devices. The color to be converted can be adjusted by appropriately selecting the substituent of the polycyclic aromatic compound of the present invention, the binder resin used in the wavelength conversion composition described below, and the like. The wavelength conversion material can be prepared as a wavelength conversion composition containing the polycyclic aromatic compound of the present invention. Moreover, you may form a wavelength conversion film using this composition for wavelength conversion.

The wavelength conversion composition may contain a binder resin, other additives, and a solvent in addition to the polycyclic aromatic compound of the present invention. As the binder resin, for example, those described in paragraphs 0173 to 0176 of International Publication No. 2016/190283 can be used. As other additives, compounds described in paragraphs 0177 to 0181 of International Publication No. 2016/190283 can be used. As for the solvent, the description of the solvent contained in the above-mentioned composition for forming a light emitting layer can be referred to.

The wavelength conversion film includes a wavelength conversion layer formed by curing a wavelength conversion composition. As a method for producing a wavelength conversion layer from a wavelength conversion composition, a known film forming method can be referred to. The wavelength conversion film may consist only of a wavelength conversion layer formed from a composition containing the polycyclic aromatic compound of the present invention, and may include other wavelength conversion layers (for example, converting blue light into green light or red light). A wavelength conversion layer, a wavelength conversion layer that converts blue light or green light into red light) may be included. Furthermore, the wavelength conversion film may include a barrier layer for preventing deterioration of the base layer and color conversion layer due to oxygen, moisture, or heat.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. First, a synthesis example of a polycyclic aromatic compound will be explained below.

<Synthesis of compounds>
Synthesis example (1): Synthesis of compound (1)

Under a nitrogen atmosphere, intermediate (int-1-1) (54.1 g), 1-t-butyl-3,4,5-trichlorobenzene (23.8 g), dichlorobis[di-t-butyl ( 4-Dimethylaminophenyl)phosphino]palladium(II) (Pd-132, 0.9 g), sodium-t-butoxide (NaOtBu, 14.4 g) and toluene (200 ml) were placed in a flask and heated at 110°C for 7 hours. did. After the reaction was completed, water and ethyl acetate were added to the reaction solution and stirred, and then the organic layer was separated and washed with water. Thereafter, the crude product obtained by concentrating the organic layer was purified using a silica gel short pass column (eluent: heptane/toluene = 1/1 (volume ratio)) to obtain the intermediate (int-1-2). 69.0g was obtained.

Under a nitrogen atmosphere, intermediate (int-1-2) (35.0 g), intermediate (int-1-3) (19.4 g), dichlorobis[di-t-butyl (4-dimethylaminophenyl) as a palladium catalyst ) Phosphino]palladium(II) (Pd-132, 0.6 g), sodium-t-butoxide (NaOtBu, 7.2 g) and toluene (100 ml) were placed in a flask and heated at 110° C. for 9 hours. After the reaction was completed, water and ethyl acetate were added to the reaction solution and stirred, and then the organic layer was separated and washed with water. Thereafter, the crude product obtained by concentrating the organic layer was purified using a silica gel short pass column (eluent: heptane/toluene = 1/1 (volume ratio)) to obtain the intermediate (int-1-4). 24.2g was obtained.

A 1.60 M t-butyllithium pentane solution (12.5 ml) was added to a flask containing intermediate (int-1-4) (10.5 g) and t-butylbenzene (100 ml) at 0°C under a nitrogen atmosphere. ) was added. After the dropwise addition was completed, the temperature was raised to 70°C and the mixture was stirred for 0.5 hours, after which components with a boiling point lower than t-butylbenzene were distilled off under reduced pressure. The mixture was cooled to −50° C., boron tribromide (5.0 g) was added, and the mixture was heated to room temperature and stirred for 0.5 hours. Thereafter, the mixture was cooled to 0° C. again, N,N-diisopropylethylamine (1.8 g) was added, and the mixture was stirred at room temperature until the heat generation subsided, then heated to 100° C. and stirred for 1 hour. The reaction solution was cooled to room temperature, and an aqueous sodium acetate solution cooled in an ice bath was added, followed by ethyl acetate to separate the layers. After concentrating the organic layer, it was purified using a silica gel short column (eluent: chlorobenzene). Compound (1) was obtained by recrystallizing the obtained crude product from toluene (6.9 g).

ＡＰＣＩ－ＭＳ（大気圧化学イオン化質量分析）によりｍ／ｚ（Ｍ＋Ｈ）＝１０２５．６９の目的物であることを確認した。

It was confirmed by APCI-MS (Atmospheric Pressure Chemical Ionization Mass Spectrometry) that it was the target product with m/z (M+H)=1025.69.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１０３．７２の目的物であることを確認した。 Synthesis Example (2): Synthesis of Compound (4) Compound (4) was obtained from the intermediate (int-4-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1103.72.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１０７．７７の目的物であることを確認した。 Synthesis Example (3): Synthesis of Compound (5) Compound (5) was obtained from the intermediate (int-5-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1107.77.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１０７．７３の目的物であることを確認した。 Synthesis Example (4): Synthesis of Compound (6) Compound (6) was obtained from the intermediate (int-6-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1107.73.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１２３７．８４の目的物であることを確認した。 Synthesis Example (5): Synthesis of Compound (7) Compound (7) was obtained from the intermediate (int-7-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1237.84.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１０４９．６９の目的物であることを確認した。 Synthesis Example (6): Synthesis of Compound (8) Compound (8) was obtained from the intermediate (int-8-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1049.69.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１２２１．８１の目的物であることを確認した。 Synthesis Example (7): Synthesis of Compound (12) Compound (12) was obtained from the intermediate (int-12-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1221.81.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１３１４．８７の目的物であることを確認した。 Synthesis Example (8): Synthesis of Compound (13) Compound (13) was obtained from the intermediate (int-13-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1314.87.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１３３８．８７の目的物であることを確認した。 Synthesis Example (9): Synthesis of Compound (14) Compound (14) was obtained from the intermediate (int-14-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1338.87.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１３７２．９５の目的物であることを確認した。 Synthesis Example (10): Synthesis of Compound (16) Compound (16) was obtained from the intermediate (int-16-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1372.95.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１０２７．７０の目的物であることを確認した。 Synthesis Example (11): Synthesis of Compound (17) Compound (17) was obtained from the intermediate (int-17-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1027.70.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝９１９．６１の目的物であることを確認した。 Synthesis Example (12): Synthesis of Compound (18) Compound (18) was obtained from the intermediate (int-18-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=919.61.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１０４４．８１の目的物であることを確認した。 Synthesis Example (13): Synthesis of Compound (19) Compound (19) was obtained from the intermediate (int-19-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1044.81.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１０５３．６３の目的物であることを確認した。 Synthesis Example (14): Synthesis of Compound (24) Compound (24) was obtained from the intermediate (int-24-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1053.63.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１６１．７８の目的物であることを確認した。 Synthesis Example (15): Synthesis of Compound (25) Compound (25) was obtained from the intermediate (int-25-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1161.78.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１６３．７４の目的物であることを確認した。 Synthesis Example (16): Synthesis of Compound (26) Compound (26) was obtained from the intermediate (int-26-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1163.74.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１２０７．７６の目的物であることを確認した。 Synthesis Example (17): Synthesis of Compound (29) Compound (29) was obtained from the intermediate (int-29-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1207.76.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１８６．８１の目的物であることを確認した。 Synthesis Example (18): Synthesis of Compound (35) Compound (35) was obtained from the intermediate (int-35-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1186.81.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１２５．６８の目的物であることを確認した。 Synthesis Example (19): Synthesis of Compound (37) Compound (37) was obtained from the intermediate (int-37-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1125.68.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１０９．７５の目的物であることを確認した。 Synthesis Example (20): Synthesis of Compound (40) Compound (40) was obtained from the intermediate (int-40-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1109.75.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１２００．７３の目的物であることを確認した。 Synthesis Example (21): Synthesis of Compound (42) Compound (42) was obtained from the intermediate (int-42-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1200.73.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１２０５．６９の目的物であることを確認した。 Synthesis Example (22): Synthesis of Compound (43) Compound (43) was obtained from the intermediate (int-43-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1205.69.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１０９５．６８の目的物であることを確認した。 Synthesis Example (23): Synthesis of Compound (45) Compound (45) was obtained from the intermediate (int-45-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1095.68.

ＡＰＣＩ－ＭＳによりｍ／ｚ（Ｍ＋Ｈ）＝１１９１．７７の目的物であることを確認した。 Synthesis Example (24): Synthesis of Compound (46) Compound (46) was obtained from the intermediate (int-46-4) in the same manner as in Synthesis Example (1).

It was confirmed by APCI-MS that it was the desired product with m/z (M+H)=1191.77.

Next, the preparation and evaluation of an organic EL device using the polycyclic aromatic compound of the present invention will be described.

<Configuration of organic EL element>
[Element configuration A]
The material composition of each layer in the organic EL device of Example A-1 is shown in Table 1 below.

"HI", "HAT-CN", "HT-1", "HT-2", "BH", "ET-1", "ET-2", "Liq", JP2019195060 in Tables 1 and 2 "Comparative compound (1)" described in "Comparative compound (1)" described in CN112961174, "Comparative compound (3)" described in WO2021107699, and "Comparative compound (4)" described in International Publication No. 2015/102118. The chemical structure is shown below.

(Example A-1)
A 26 mm x 28 mm x 0.7 mm glass substrate (manufactured by Optoscience Co., Ltd.) is used as a transparent support substrate, with ITO formed to a thickness of 180 nm by sputtering and polished to a thickness of 150 nm. This transparent support 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 Liq, LiF, and aluminum, and an aluminum nitride vapor deposition boat containing Liq, LiF, and aluminum, respectively, were installed.

The following layers are sequentially formed on the ITO film of the transparent support substrate. The pressure in the vacuum chamber was reduced to 5 × 10 ^-4 Pa, and first, HI was heated and deposited to a film thickness of 40 nm, then HAT-CN was heated and deposited to a film thickness of 5 nm, Next, HT-1 is heated and deposited to a thickness of 45 nm, and then HT-2 is heated and deposited to a thickness of 10 nm to form a hole layer consisting of four layers. did. Next, BH and compound (1-1) were simultaneously heated and deposited to a thickness of 25 nm to form a light-emitting layer. The deposition rate was adjusted so that the mass ratio of BH and compound (1-1) was approximately 97:3. Furthermore, ET-1 was heated and deposited to a thickness of 5 nm, and then ET-2 and Liq were simultaneously heated and deposited to a thickness of 25 nm to form a two-layer electronic layer. Formed. The deposition rate was adjusted so that the mass ratio of ET-2 to Liq was approximately 50:50. The deposition rate of each layer was 0.01-1 nm/sec. Thereafter, LiF is heated and deposited to a thickness of 1 nm at a deposition rate of 0.01 to 0.1 nm/sec, and then aluminum is heated and deposited to a thickness of 100 nm to form a cathode. An organic EL device was obtained.

(Examples A-2 to A-24)
The organic compounds of Examples A-2 to A-24 and Comparative Examples 1 to 4 were prepared in the same manner as in Example A-1 except that each material listed in Table 2 was used instead of compound (1-1). An EL element was obtained.

[Evaluation items and evaluation method]
Evaluation items include drive voltage (V), emission wavelength (nm), CIE chromaticity (x, y), external quantum efficiency (%), maximum wavelength of emission spectrum (nm), and half-width (nm). . For these evaluation items, for example, values at the time of light emission of 1000 cd/m ² can be used.

There are two types of quantum efficiency for light-emitting devices: internal quantum efficiency and external quantum efficiency.Internal quantum efficiency is when external energy injected as electrons (or holes) into the light-emitting layer of a light-emitting device is converted purely into photons. It shows the percentage of On the other hand, external quantum efficiency is calculated based on the amount of photons emitted to the outside of the light emitting element, and some of the photons generated in the light emitting layer are absorbed inside the light emitting element or continue to be reflected. Since the light is not emitted to the outside of the light emitting device, the external quantum efficiency is lower than the internal quantum efficiency.

The method for measuring spectral radiance (emission spectrum) and external quantum efficiency is as follows. Using a voltage/current generator R6144 manufactured by Advantest Co., Ltd., a voltage such that the luminance of the device becomes 1000 cd/m ² is applied to cause the device to emit light. Spectral radiance in the visible light region is measured in the direction perpendicular to the light emitting surface using a spectral radiance meter SR-3AR manufactured by TOPCON. Assuming that the light-emitting surface is a completely diffusing surface, the number of photons at each wavelength is obtained by dividing the measured spectral radiance value of each wavelength component by the wavelength energy and multiplying it by π. Next, the number of photons is integrated over the entire observed wavelength range to obtain the total number of photons emitted from the element. The value obtained by dividing the applied current value by the elementary charge is the number of carriers injected into the device, and the value obtained by dividing the total number of photons emitted from the device by the number of carriers injected into the device is the external quantum efficiency. Further, the half-width of the emission spectrum is determined as the width between the upper and lower wavelengths at which the intensity is 50%, centering on the maximum emission wavelength.

[Evaluation results of element configuration A]
For the organic EL devices of Examples A-1 to A-24 and Comparative Examples 1 to 4, a DC voltage was applied with the ITO electrode as the anode and the LiF/aluminum electrode as the cathode, and the driving voltage at the time of 1000 cd/m ² emission ( V) and external quantum efficiency (%) were measured.
The results are shown in Table 2.

The polycyclic aromatic compound of the present invention is useful as a material for organic devices, particularly as a material for a light emitting layer for forming a light emitting layer of an organic electroluminescent device. By using the polycyclic aromatic compound of the present invention as a dopant for a light emitting layer, an organic electroluminescent device that emits light at low voltage and with high efficiency can be obtained.

100 Organic electroluminescent device 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 (13)

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

In formula (1),
Ring A, Ring B, Ring C1, and Ring C2 are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,
Y ¹ is B, P, P=O, P=S, Al, Ga, As, Si-R ^YI , or Ge-R ^YG , and R ^YI and R ^YG are each substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl;
X ¹ is >O, >N-R ^NX , >C(-R ^CX ) ₂ , >Si(-R ^IX ) ₂ , >S, or >Se, and R ^NX , R ^CX , and R ^IX are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two of >C(-R ^CX ) ₂ R ^CX may be bonded to each other to form a ring, and two R ^IX of >Si(-R) ₂ may be bonded to each other to form a ring, R ^NX , at least one R ^CX , and At least one R ^IX may be bonded to at least one of ring A or ring B via a single bond or a linking group,
Cy ¹ and Cy ² are each independently substituted or unsubstituted aryl fused with at least one cycloalkane, and at least one hydrogen in the cycloalkane may have a substituent, At least one -CH ₂ - in the cycloalkane may be substituted with -O-,
At least one of the aryl rings or heteroaryl rings in the portion other than Cy ¹ and Cy ² of the structure may be fused with at least one cycloalkane, and at least one hydrogen in the cycloalkane has a substituent. and at least one -CH ₂ - in the cycloalkane may be substituted with -O-,
At least one hydrogen in the structure may be replaced with cyano, halogen, or deuterium. Cy ¹ and Cy ² are each independently a group represented by any one of formula (C-1), formula (C-2), formula (C-3), or formula (C-4) , the polycyclic aromatic compound according to claim 1;

In the formula, Me is methyl, and * indicates the bonding position. The polycyclic aromatic compound according to claim 2, wherein both the C1 ring and the C2 ring are benzene rings, and both Cy ¹ and Cy ² are bonded to the para position of N. The polycyclic aromatic compound according to claim 1, wherein the structural unit represented by formula (1) is a structural unit represented by formula (2);

In formula (2), Cy ¹ , Cy ² , X ¹ and Y ¹ are respectively synonymous with Cy ¹ , Cy ² , X ¹ and Y ¹ in formula (1),
R ^Za is hydrogen or a substituent,
Z is each independently -C(-R ^Z )= or -N=, R ^Z is each independently hydrogen or a substituent, and Z=Z is each independently >N-R ^NZ , >O, >C(-R ^CZ ) ₂ , >Si(-R ^IZ ) ₂ , >S, or >Se, and R ^NZ , R ^CZ and R ^IZ each independently represent hydrogen, Substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two R ^CZ may be bonded to each other to form a ring. , two R ^IZ may be bonded to each other to form a ring,
At least one of the aryl rings or heteroaryl rings in the portion other than Cy ¹ and Cy ² of the structure may be fused with at least one cycloalkane, and at least one hydrogen in the cycloalkane has a substituent. and at least one -CH ₂ - in the cycloalkane may be substituted with -O-,
At least one hydrogen in the structure may be replaced with cyano, halogen, or deuterium. The polycyclic aromatic compound according to claim 4, comprising a partial structure represented by formula (b-1), formula (b-17), or formula (b-18);

In the formula, each R is independently a substituent, and n is an integer of 0 to 4. 5. The polycyclic aromatic compound according to claim 4, wherein R ^Za is unsubstituted alkyl or alkyl-substituted diarylamino. The polycyclic aromatic compound according to claim 4, wherein X ¹ is >NR ^NX and R ^NX is substituted or unsubstituted aryl. The polycyclic aromatic compound according to claim 1, which is represented by any one of the following formulas.

In the formula, Me is methyl, tBu is t-butyl, and D is deuterium. A material for an organic device, comprising the polycyclic aromatic compound according to any one of claims 1 to 8. comprising a pair of electrodes consisting of an anode and a cathode, and a light emitting layer disposed between the pair of electrodes, the light emitting layer containing the polycyclic aromatic compound according to any one of claims 1 to 8. , organic electroluminescent device. The organic electroluminescent device according to claim 10, wherein the light emitting layer contains a host and the polycyclic aromatic compound as a dopant. The organic electroluminescent device according to claim 11, wherein the host is an anthracene compound, a fluorene compound, or a dibenzochrysene compound. A display device or a lighting device comprising the organic electroluminescent element according to claim 10.