Polycyclic aromatic compound

Abstract

To provide a novel compound which is useful as an organic device material such as an organic EL element and the like.SOLUTION: A polycyclic aromatic compound has a structure formed of one, two or more of structural units represented by formula (1A-1). (In formula (1A-1), an A2 ring, an A3 ring, and an A4 ring are mutually independently a substituted or unsubstituted aryl or heteroaryl ring; an A1 ring and an A5 ring are mutually independently a substituted or unsubstituted aryl ring or heteroaryl ring, a cycloalkyl or cycloheteroalkyl ring; n, m, q and r are mutually independently 0 or 1, provided that n+m=1 and q+r is not 0; Y1 is B or the like; each of L1 to L4 is mutually independently a single bond or a linking group; and at least one hydrogen in the structure can be substituted by cyano, halogen or deuterium.)SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to polycyclic aromatic compounds. In particular, the present invention relates to polycyclic aromatic compounds containing nitrogen and boron. The present invention also relates to materials for organic devices containing the above polycyclic aromatic compounds, organic electroluminescent devices, and display devices and lighting devices.

Background Art

[0002] Conventionally, display devices using light-emitting devices that emit light by an electric field have been variously studied because they can save power and be made thinner. Furthermore, organic electroluminescent devices made of organic materials have been actively studied because they can be easily made lighter and larger. In particular, the development of organic materials having light-emitting characteristics such as blue, which is one of the three primary colors of light, and the development of organic materials having charge transport capabilities (capable of becoming semiconductors or superconductors) such as holes and electrons have been actively studied so far, regardless of whether they are high molecular compounds or low molecular compounds.

[0003] An organic electroluminescent device has a structure composed of a pair of electrodes including an anode and a cathode, and one or more layers containing an organic compound disposed between the pair of electrodes. The layer containing the organic compound includes a light-emitting layer and a charge transport / injection layer that transports or injects charges such as holes and electrons, and various appropriate organic materials have been developed for these layers.

[0004] Among them, Patent Document 1 discloses that a polycyclic aromatic compound containing boron is useful as a material for an organic electroluminescent device or the like. It has been reported that an organic electroluminescent device containing this polycyclic aromatic compound has good external quantum efficiency.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] As described above, various materials have been developed as materials used in organic EL elements. However, in order to increase the options for materials for organic EL elements, the development of materials composed of compounds different from the conventional ones is desired. An object of the present invention is to provide such a material.

Means for Solving the Problems

[0007] The present inventors have intensively studied to solve the above problems, and have succeeded in producing a novel polycyclic aromatic compound having a structure similar to that of the compound described in Patent Document 1 and having more excellent light emission characteristics.

[0008] Specifically, the present invention has the following configuration.

[0009] <1> A polycyclic aromatic compound having a structure composed of one or more structural units represented by the following formula (1A-1).

Chemical formula

[0010] <2> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by the following formula (1a-1). [Chemical formula] In formula (1a-1), Y 1 is B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R, and R in the Si-R and Ge-R is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl; L 1 L 2 L 3 and L 4 are each independently a single bond, substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, substituted or unsubstituted alkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted alkenylene, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, and R in >N-R, R in >Si(-R)2, and R in >C(-R)2 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two Rs in all >Si(-R)2 and two Rs in >C(-R)2 do not combine with each other to form a ring or form a ring, and at least one of R in >N-R, R in >C(-R)2, and R in >Si(-R)2 is each independently C-R Z R in Z which is Z is not bonded or is bonded by at least one of -O-, -S-, -C(-R)2- or a single bond; n, m, q, and r are each independently 0 or 1, and in the case of 0, each independently means that R 1 is present instead of L 1 L 2 L 3 or L 4 but n + m = 1 and q + r is not 0; Z is, independently of each other, N or C-R 1 or Z=Z is, independently of each other, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, and the C-R 1 of the R 1 is, independently of each other, hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboril, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these is unsubstituted or substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl, the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, the two aryls of the diarylboril are not bonded to each other or are bonded via a single bond or a linking group; Two adjacent Rs 1are not bonded to each other to form an aryl ring or a heteroaryl ring, or form an aryl ring or a heteroaryl ring, and at least one hydrogen of the formed aryl ring and the formed heteroaryl ring is each independently unsubstituted or substituted with aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these is unsubstituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl, the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, the two aryls of the diarylboryl are not bonded to each other or are bonded via a single bond or a linking group, the R in >N-R, >C(-R)2, and >Si(-R)2 is each independently hydrogen, aryl, heteroaryl, alkyl, or cycloalkyl, and at least one hydrogen in these is unsubstituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl, and the two Rs in >C(-R)2 and >Si(-R)2 do not bond to each other to form a ring or form a ring; The polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1a-1) is not condensed or is condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane is unsubstituted or substituted, at least one -CH2- in the cycloalkane is not substituted or is substituted with -O- or -S-, and; At least one hydrogen in the structure represented by formula (1a-1) is unsubstituted or substituted with cyano, halogen, or deuterium.

[0011] <3> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by the following formula (1b-1) or formula (1b-2), respectively.

Chemical formula

[0012] <4> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by the following formula (1c-1), formula (1c-2), formula (1c-3), or formula (1c-4).

Chemical formula

[0013] <5> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by formula (1d-1) or formula (1d-2).

Chemical formula

[0014] <6> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by formula (1e-1), formula (1e-2), formula (1e-3), or formula (1e-4).

Chemical formula

[0015] <7> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by formula (1f-1) or formula (1f-2). [Chemical formula] In formula (1f-1) and formula (1f-2), x is an integer from 1 to 3; Y 1is B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R, where R of the Si-R and Ge-R is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl; L 1 、L 2 、L 3 、and L 4 are each independently a single bond, substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, substituted or unsubstituted alkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted alkenylene, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where R of >N-R, R of >Si(-R)2, and R of >C(-R)2 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and two Rs of all >Si(-R)2 and two Rs of >C(-R)2 do not combine with each other to form a ring or form a ring, and at least one of R of >N-R, R of >C(-R)2, and R of >Si(-R)2 is independently R in Z of C-R Z and is not bonded or is bonded by at least one of R in Z of C-R Z to -O-, -S-, -C(-R)2- or a single bond; n, m, q, and r are each independently 0 or 1, and when 0, each independently means that hydrogen or a substituent is present instead of L 1 、L 2 、L 3 or L 4 respectively, provided that n + m = 1 and q + r ≠ 0; A is, independently of each other, >(CR)-, where R in the >(CR)- is hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl; E is, independently of each other, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where R in >N-R, R in >Si(-R)2, and R in >C(-R)2 are, independently of each other, hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and the two Rs in all >Si(-R)2 and the two Rs in >C(-R)2 do not combine with each other to form a ring or do form a ring; E is, independently of each other, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where R in >N-R, R in >Si(-R)2, and R in >C(-R)2 are, independently of each other, hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and the two Rs in all >Si(-R)2 and the two Rs in >C(-R)2 do not combine with each other to form a ring or do form a ring; Z is, independently of each other, N or C-R 1 or Z=Z is, independently of each other, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where R in C-R 1 of 1Each is independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboril, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these is unsubstituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl, and the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, the two aryls of the diarylboril are not bonded to each other or are bonded via a single bond or a linking group; Two adjacent Rs 1are not bonded to each other to form an aryl ring or a heteroaryl ring, or form an aryl ring or a heteroaryl ring, and at least one hydrogen of the formed aryl ring and the formed heteroaryl ring is respectively not substituted or substituted with aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these is not substituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl, the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, the two aryls of the diarylboryl are not bonded to each other or are bonded via a single bond or a linking group, the Rs of the >N-R, the >C(-R)2 and the >Si(-R)2 are each independently hydrogen, aryl, heteroaryl, alkyl, cycloalkyl, and at least one hydrogen in these is not substituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl, and the two Rs of the >C(-R)2 and the >Si(-R)2 do not bond to each other to form a ring or form a ring; The polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1f-1) and formula (1f-2) is not condensed or condensed with at least one cycloalkane, at least one hydrogen in the cycloalkane is not substituted or substituted, at least one -CH2- in the cycloalkane is not substituted or substituted with -O- or -S-, and; At least one hydrogen in the structures represented by Formula (1f-1) and Formula (1f-2) is unsubstituted or substituted with cyano, halogen, or deuterium.

[0016] <8> The polycyclic aromatic compound according to <1>, wherein the structural units are structural units represented by the following Formula (1g-1) or Formula (1g-2), respectively.

Chemical formula

[0017] <9> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by the following formula (1h-1), formula (1h-2), formula (1h-3), or formula (1h-4).

Chemical formula

[0018] <10> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by Formula (1i-1) or Formula (1i-2).

Chemical formula

[0019] <11> The polycyclic aromatic compound according to <1>, wherein the structural unit is a structural unit represented by formula (1k-1), formula (1k-2), formula (1k-3), or formula (1k-4).

Chemical formula

[0020] <12> The polycyclic aromatic compound according to <1>, represented by any of the following structural formulas.

Chemical formula

[0021] <13> A polycyclic aromatic compound described in <1>, which is represented by any of the following structural formulas.

Chemical formula

[0022] <14> A material for an organic device, which contains the polycyclic aromatic compound described in any of <1> to <13>.

[0023] <15> An organic electroluminescent device, which includes a pair of electrodes composed of an anode and a cathode, and a light-emitting layer disposed between the pair of electrodes, wherein the light-emitting layer contains the polycyclic aromatic compound described in any of <1> to <13>.

[0024] <16> The organic electroluminescent device described in <15>, wherein the light-emitting layer contains a host and the polycyclic aromatic compound as a dopant.

[0025] <17> A display device or a lighting device including the organic electroluminescent device described in either <15> or <16>.

Advantages of the Invention

[0026] According to the present invention, a novel polycyclic aromatic compound useful as a material for an organic device such as an organic electroluminescent device is provided. The polycyclic aromatic compound of the present invention can be used in the manufacture of an organic device such as an organic electroluminescent device.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0028] Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be based on typical embodiments or specific examples, but the present invention is not limited to such embodiments. In this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as the lower limit value and the upper limit value. Also, in this specification, "hydrogen" in the description of the structural formula means "hydrogen atom (H)". In this specification, an organic electroluminescent device may be referred to as an organic EL device.

[0029] In this specification, a chemical structure or a substituent may be represented by the number of carbon atoms. However, when a substituent is substituted on a chemical structure, or when a further substituent is substituted on a substituent, etc., the number of carbon atoms means the number of carbon atoms of each of the chemical structure and the substituent, and does not mean the total number of carbon atoms of the chemical structure and the substituent, or the total number of carbon atoms of the substituent and the substituent. For example, "substituent B having Y carbon atoms substituted with substituent A having X carbon atoms" means that "substituent A having X carbon atoms" is substituted on "substituent B having Y carbon atoms", and Y carbon atoms is not the total number of carbon atoms of substituent A and substituent B. Also, for example, "substituent B having Y carbon atoms substituted with substituent A" means that "(substituent A without carbon number limitation)" is substituted on "substituent B having Y carbon atoms", and Y carbon atoms is not the total number of carbon atoms of substituent A and substituent B.

[0030] Since the chemical structural formulas (including general formulas depicted by Markush formulas) described in this specification are planar structural formulas, in reality, various isomeric structures such as enantiomers, diastereoisomers, and rotational isomers may exist. In this specification, unless otherwise specified, the described compounds may have any isomeric structure conceivable from their planar structural formulas, or may be any mixture of arbitrary ratios composed of possible isomers.

[0031] This specification describes a number of structural formulas of aromatic compounds. Although the aromatic compounds are described by combining double bonds and single bonds, in reality, due to the resonance of π electrons, for a single substance, there are multiple equivalent resonance structures such as the alternating replacement of double bonds and single bonds. In this specification, only one resonance structural formula is described for one substance, but unless otherwise specified, other resonance structural formulas that are organically equivalent are also considered to be included. This is referred to in descriptions such as "Z=Z" described later. That is, for example, regarding "Z=Z" in formula (1a-1) described later, it is as follows when giving an example. However, it is not limited to this, and it is naturally applicable not only to the one described resonance structural formula but also to other conceivable equivalent resonance structural formulas.

Chem.

[0032] In addition, this specification uses two expressions: "may be" and "is not or is". These two expressions have the same meaning.

[0033] <Polycyclic Aromatic Compound> The polycyclic aromatic compound of the present invention is a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1A-1). The polycyclic aromatic compound of the present invention has a high photoluminescence quantum yield (PLQY), a narrow emission half-width, and excellent color purity.

[0034]

Chem.

[0035] In formula (1A-1), the A2 ring, the A3 ring, and the A4 ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring, and the A1 ring and the A5 ring are each independently a substituted or unsubstituted aryl ring, a substituted or unsubstituted heteroaryl ring, a substituted or unsubstituted cycloalkyl ring, or a cycloheteroalkyl ring.

[0036] In formula (1A-1), examples of the "aryl ring" in the A1 ring, the A2 ring, the A3 ring, the A4 ring, and the A5 ring include aryl rings having 6 to 30 carbon atoms, preferably aryl rings having 6 to 16 carbon atoms, more preferably aryl rings having 6 to 12 carbon atoms, and particularly preferably aryl rings having 6 to 10 carbon atoms.

[0037] Specific examples of the "aryl ring" include a benzene ring which is a monocyclic system, a biphenyl ring which is a bicyclic system, a naphthalene ring which is a condensed bicyclic system, an indene ring, a terphenyl ring (m-terphenyl, o-terphenyl, p-terphenyl) which is a tricyclic system, an acenaphthylene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, an anthracene ring which are condensed tricyclic systems, a triphenylene ring, a pyrene ring, a naphthacene ring, a chrysene ring which are condensed tetracyclic systems, a perylene ring, a pentacene ring which are condensed pentacyclic systems, etc. In addition, the fluorene ring, the benzofluorene ring, and the indene ring each include a structure in which a fluorene ring, a benzofluorene ring, a cyclopentane ring, etc. are spiro-bonded. Note that the fluorene ring, the benzofluorene ring, and the indene ring also include those in which two of the two hydrogens of methylene are each substituted with an alkyl such as methyl as the first substituent described below, resulting in a dimethylfluorene ring, a dimethylbenzofluorene ring, a dimethylindene ring, etc.

[0038] In formula (1A-1), examples of the "heteroaryl ring" in the A1 ring, A2 ring, A3 ring, A4 ring, and A5 ring include heteroaryl rings having 2 to 30 carbon atoms, preferably heteroaryl rings having 2 to 25 carbon atoms, more preferably heteroaryl rings having 2 to 20 carbon atoms, still more preferably heteroaryl rings having 2 to 15 carbon atoms, and particularly preferably heteroaryl rings having 2 to 10 carbon atoms. Examples of the "heteroaryl ring" also include heterocyclic rings containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen in addition to carbon as ring-constituting atoms.

[0039] Specific "heteroaryl rings" include, for example, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, oxadiazole ring, thiadiazole ring, triazole ring, tetrazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyridazine ring, pyrazine ring, triazine ring, indole ring, isoindole ring, 1H-indazole ring, benzimidazole ring, benzoxazole ring, benzothiazole ring, 1H-benzotriazole ring, quinoline ring, isoquinoline ring, cinnoline ring, quinazoline ring, quinoxaline ring, phthalazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, carboline ring, acridine ring, phenoxathiin ring, phenoxazine ring, phenothiazine ring, phenazine ring, phenazasiline ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, furazan ring, thianthrene ring, indolocarbazole ring, benzindolocarbazole ring, benzobenzindolocarbazole ring, naphthobenzofuran ring, dioxin ring, dihydroacridine ring, xanthene ring, thioxanthene ring, dibenzodioxin ring, etc. Further, in the dihydroacridine ring, xanthene ring, thioxanthene ring, two of the two hydrogens of methylene are each substituted with an alkyl such as methyl as the first substituent described later, and those which become dimethyldihydroacridine ring, dimethylxanthene ring, dimethylthioxanthene ring, etc. are also preferable. Also, the bipyridine ring, phenylpyridine ring, pyridylphenyl ring which are bicyclic systems, and the terpyridyl ring, bispyridylphenyl ring, pyridylbiphenyl ring which are tricyclic systems are also mentioned as "heteroaryl rings". Further, the pyran ring is also included in the "heteroaryl ring".

[0040] Also, the following formula (BO) is also included in the heteroaryl ring.

Chemical formula

[0041] In formula (1A-1), examples of the "cycloalkyl ring" in the A1 ring and the A5 ring include cycloalkyl rings having 6 to 30 carbon atoms, preferably cycloalkyl rings having 6 to 16 carbon atoms, more preferably cycloalkyl rings having 6 to 12 carbon atoms, and particularly preferably cycloalkyl rings having 6 to 10 carbon atoms.

[0042] Specific examples of the cycloalkyl ring include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornenine, bicyclo[1.1.0]butane, bicyclo[1.1.1]pentane, 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, diamantane, decahydronaphthalene, decahydroazulene, and C1-C4 alkyl (especially methyl) substituents thereof.

[0043] In formula (1A-1), examples of the "cycloheteroalkyl ring" in the A1 ring and the A5 ring include cycloheteroalkyl rings having 4 to 30 carbon atoms, preferably cycloheteroalkyl rings having 4 to 16 carbon atoms, more preferably cycloheteroalkyl rings having 4 to 12 carbon atoms, and particularly preferably cycloheteroalkyl rings having 4 to 10 carbon atoms.

[0044] The cycloheteroalkyl ring means a ring in which one or more carbon atoms of the cycloalkyl ring are replaced by heteroatoms (such as oxygen, nitrogen, sulfur). Specific examples of the cycloheteroalkyl ring include tetrahydropyrrole ring, tetrahydrofuran ring, tetrahydrothiophene ring, piperidine ring, pyrrolidine ring, tetrahydropyran ring, tetrahydrothiopyran ring, dioxane ring, oxathiane ring, dithiane ring, morpholine ring, piperazine ring, and the like.

[0045] At least one hydrogen in the above-mentioned "aryl ring", "heteroaryl ring", "cycloalkyl ring" or "cycloheteroalkyl ring" is a substituted or unsubstituted "aryl", a substituted or unsubstituted "heteroaryl", a substituted or unsubstituted "diaryl amino", a substituted or unsubstituted "diheteroaryl amino", a substituted or unsubstituted "aryl heteroaryl amino", a substituted or unsubstituted "diaryl boryl", a substituted or unsubstituted "alkyl", a substituted or unsubstituted "cycloalkyl", a substituted or unsubstituted "alkenyl", a substituted or unsubstituted "alkoxy", a substituted or unsubstituted "aryloxy", a substituted or unsubstituted "arylthio", or a substituted "silyl", which is a first substituent. It should be noted that the two aryls of the "diaryl amino" are not bonded to each other or are bonded via a linking group, the two heteroaryls of the "diheteroaryl amino" are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the "aryl heteroaryl amino" are not bonded to each other or are bonded via a linking group, and the two aryls of the "diaryl boryl" are not bonded to each other or are bonded via a single bond or a linking group. Regarding these terms and their preferred ranges, unless otherwise specified, the descriptions in the specification can be referred to.

[0046] Specifically, examples of the "aryl" include aryls having 6 to 30 carbon atoms, preferably aryls having 6 to 24 carbon atoms, more preferably aryls having 6 to 20 carbon atoms, still more preferably aryls having 6 to 16 carbon atoms, particularly preferably aryls having 6 to 12 carbon atoms, and most preferably aryls having 6 to 10 carbon atoms.

[0047] Specific aryls include, for example, phenyl which is a monocyclic aryl, (2-, 3-, 4-) biphenylyl which is a bicyclic aryl, (1-, 2-) naphthyl which is a condensed bicyclic aryl, (2-, 3-, 4-, 5-, 6-, 7-) indenyl, terphenyl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl-5'-yl, o-terphenyl-3'-yl, o-terphenyl-4'-yl, p-terphenyl-2'-yl, m-terphenyl-2-yl, m-terphenyl-3-yl, m-terphenyl-4-yl, o-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, p-terphenyl-4-yl) which is a tricyclic aryl, acenaphthylene-(1-, 3-, 4-, 5-)yl, fluorene-(1-, 2-, 3-, 4-, 9-)yl, phenalene-(1-, 2-)yl, (1-, 2-, 3-, 4-, 9-)phenanthryl which are condensed tricyclic aryls, quarterphenyl (5'-phenyl-m-terphenyl-2-yl, 5'-phenyl-m-terphenyl-3-yl, 5'-phenyl-m-terphenyl-4-yl, m-quarterphenyl) which is a tetracyclic aryl, triphenylene-(1-, 2-)yl, pyrene-(1-, 2-, 4-)yl, naphthacene-(1-, 2-, 5-)yl which are condensed tetracyclic aryls, perylene-(1-, 2-, 3-)yl, pentacene-(1-, 2-, 5-, 6-)yl which are condensed pentacyclic aryls, and the like.

[0048] In addition, examples of "heteroaryl" include heteroaryls having 2 to 30 carbon atoms, preferably heteroaryls having 2 to 25 carbon atoms, more preferably heteroaryls having 2 to 20 carbon atoms, still more preferably heteroaryls having 2 to 15 carbon atoms, and particularly preferably heteroaryls having 2 to 10 carbon atoms. Further, examples of heteroaryl include heterocycles containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen in addition to carbon as ring-constituting atoms.

[0049] Specific heteroaryls include, for example, furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, oxadiazolyl, furazanyl, thiadiazolyl, triazolyl, tetrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, benzo[b]thienyl, dibenzothienyl, indolyl, isoindolyl, 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolyl, quinazolinyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, carbolyl, acridinyl, phenoxazinyl, phenothiazinyl, phenazinyl, phenoxathiinyl, thianthrenyl, indolizinyl, and the like.

[0050] Also, the "alkyl" as the first substituent may be either straight-chain or branched-chain, and examples include 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-chain alkyl having 3 to 18 carbon atoms) is preferred, alkyl having 1 to 12 carbon atoms (branched-chain alkyl having 3 to 12 carbon atoms) is more preferred, alkyl having 1 to 8 carbon atoms (branched-chain alkyl having 3 to 8 carbon atoms) is further preferred, alkyl having 1 to 6 carbon atoms (branched-chain alkyl having 3 to 6 carbon atoms) is particularly preferred, and alkyl having 1 to 5 carbon atoms (branched-chain alkyl having 3 to 5 carbon atoms) is most preferred.

[0051] Specific alkyl groups 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, and the like. 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.

[0052] As a substituent containing the above-mentioned "alkyl", the tertiary-alkyl represented by the following formula (tR) is one of the particularly preferred substituents for the aryl ring or heteroaryl ring in the A ring, B ring, and C ring. This is because such a bulky substituent increases the intermolecular distance, thereby improving the luminescence quantum yield (PLQY). Also preferred are substituents in which the tertiary-alkyl represented by the formula (tR) is substituted for another substituent as the second substituent. Specifically, diarylamino substituted with tertiary-alkyl represented by (tR), carbazolyl substituted with tertiary-alkyl represented by (tR) (preferably, N-carbazolyl), or benzocarbazolyl substituted with tertiary-alkyl represented by (tR) (preferably, N-benzocarbazolyl) can be mentioned. Note that the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group. Examples of the group described as the following "first substituent" can be mentioned for "diarylamino". As the substitution form of the group of the formula (tR) for diarylamino, carbazolyl, and benzocarbazolyl, examples include those in which some or all of the hydrogens of the aryl ring or benzene ring in these groups are substituted with the group of the formula (tR).

[0053]

Chemical formula

[0054] In the formula (tR), R a , R b , and R c are each independently an alkyl having 1 to 24 carbon atoms, and any -CH2- in the alkyl is not substituted or is substituted with -O-, and the group represented by the formula (tR) substitutes at least one hydrogen in the structure containing the structural unit represented by the formula (1) at *.

[0055] R a , R b and R cThe "alkyl group having 1 to 24 carbon atoms" may be either linear or branched, and examples thereof include a linear alkyl group having 1 to 24 carbon atoms or a branched alkyl group having 3 to 24 carbon atoms, an alkyl group having 1 to 18 carbon atoms (a branched alkyl group having 3 to 18 carbon atoms), an alkyl group having 1 to 12 carbon atoms (a branched alkyl group having 3 to 12 carbon atoms), an alkyl group having 1 to 6 carbon atoms (a branched alkyl group having 3 to 6 carbon atoms), and an alkyl group having 1 to 4 carbon atoms (a branched alkyl group having 3 to 4 carbon atoms).

[0056] R in the formula (tR) of the formula (1) a , R b , and R c The total number of carbon atoms of is preferably 3 to 20, particularly preferably 3 to 10.

[0057] R a , R b , and R c Specific examples of the alkyl group 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, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl, and the like.

[0058] Examples of the group represented by the 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-1,2,2-trimethylpropyl, 1-propyl-1-methylbutyl, 1,1-dimethylhexyl, etc. Among these, t-butyl and t-amyl are preferred.

[0059] Examples of the "cycloalkyl" as the first substituent include 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, 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, etc. The cyclohexyl in this specification includes, as listed below, not only monocyclic cyclohexyl but also polycyclic ones such as adamantyl.

[0060] Specific examples of cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, 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 C1-C5 alkyl (especially methyl) substituents thereof.

[0061] Examples of the "alkoxy" as the first substituent include linear alkoxy having 1 to 24 carbon atoms or branched alkoxy having 3 to 24 carbon atoms. Alkoxy having 1 to 18 carbon atoms (branched alkoxy having 3 to 18 carbon atoms) is preferred, alkoxy having 1 to 12 carbon atoms (branched alkoxy having 3 to 12 carbon atoms) is more preferred, alkoxy having 1 to 6 carbon atoms (branched alkoxy having 3 to 6 carbon atoms) is even more preferred, and alkoxy having 1 to 5 carbon atoms (branched alkoxy having 3 to 5 carbon atoms) is particularly preferred.

[0062] Specific examples of alkoxy include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, t-amyloxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, and the like.

[0063] Examples of the "substituted silyl" as the first substituent include silyl substituted with three substituents selected from the group consisting of alkyl, cycloalkyl, and aryl. For example, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, triarylsilyl, dialkylarylsilyl, and alkyldiarylsilyl can be mentioned.

[0064] Examples of the "trialkylsilyl" include groups in which the three hydrogens in silyl are each independently substituted with alkyl, and this alkyl can cite the groups described as "alkyl" in the above-mentioned first substituent. Preferred alkyl for substitution is alkyl having 1 to 5 carbon atoms, and specifically, methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl, t-amyl, and the like can be mentioned.

[0065] Specific trialkylsilyls include trimethylsilyl, triethylsilyl, tripropylsilyl, tri-i-propylsilyl, tributylsilyl, tri-sec-butylsilyl, tri-t-butylsilyl, tri-t-amylsilyl, ethyldimethylsilyl, propyldimethylsilyl, i-propyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, t-butyldimethylsilyl, t-amyl-dimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, i-propyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, t-butyldiethylsilyl, t-amyl-diethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, t-butyldipropylsilyl, t-amyl-dipropylsilyl, methyldi-i-propylsilyl, ethyldi-i-propylsilyl, butyldi-i-propylsilyl, sec-butyldi-i-propylsilyl, t-butyldi-i-propylsilyl, t-amyl-di-i-propylsilyl, and the like.

[0066] Examples of "tricycloalkylsilyl" include groups in which the three hydrogens in the silyl group are each independently substituted with a cycloalkyl, and this cycloalkyl can cite the groups described as "cycloalkyl" in the above-mentioned first substituent. Preferred cycloalkyls for substitution are cycloalkyls 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, decahydronaphthalenyl, decahydroazulenyl, and the like.

[0067] Specific tricycloalkylsilyls include tricyclopentylsilyl, tricyclohexylsilyl, and the like.

[0068] Specific examples of dialkylcycloalkylsilyl substituted with two alkyls and one cycloalkyl and alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyls include silyl substituted with a group selected from the specific alkyls and cycloalkyls described above.

[0069] 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 silyl substituted with a group selected from the specific alkyls and aryls described above. Specific examples of triarylsilyl include, in particular, triphenylsilyl.

[0070] "Aryloxy" as the first substituent is a group in which the hydrogen of the -OH group is substituted with an aryl, and the aryl can be cited as the one described as "aryl" above.

[0071] "Arylthio" as the first substituent is a group in which the hydrogen of the -SH group is substituted with an aryl, and the aryl can be cited as the one described above.

[0072] "Alkenyl" as the first substituent includes linear 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 still more preferred, and alkenyl having 2 to 4 carbon atoms is particularly preferred. Specific examples of "alkenyl" include vinyl, allyl, butadienyl, and the like.

[0073] In addition, as the "aryl" in "diarylboril" of the first substituent, the description of aryl mentioned above can be cited. Further, these two aryls may be bonded via a single bond or a linking group (for example, >C(-R)2, >O, >S or >N-R). Here, R in >C(-R)2 and >N-R is aryl, heteroaryl, alkyl, cycloalkyl, alkoxy or aryloxy (the above are the first substituents), and at least one hydrogen of the first substituent is not further substituted with aryl, heteroaryl, alkyl or cycloalkyl (the above are the second substituents), or is substituted, and specific examples of these groups can cite the description of the first substituent mentioned above. Note that the two aryls of the diarylboril are not bonded to each other, or are bonded via a single bond or a linking group.

[0074] Regarding each of "optionally substituted diarylamino", "optionally substituted diheteroarylamino", and "optionally substituted arylheteroarylamino" as the first substituent, the aryl and heteroaryl described above as "aryl" and "heteroaryl" can be cited. Further, at least one hydrogen of aryl and heteroaryl is not substituted or is substituted, and as the substituent, the description regarding "substituted or unsubstituted" described later can be referred to, and tertiary alkyl described later is preferred. Note that the two aryls of the diarylamino are not bonded to each other, or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other, or are bonded via a linking group, and the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other, or are bonded via a linking group.

[0075] The diarylamino, diheteroarylamino, and arylheteroarylamino as the first substituent are described as "two aryls are bonded or not bonded via a linking group", "two heteroaryls are bonded or not bonded via a linking group", or "heteroaryl is bonded or not bonded via a linking group". However, this description represents, for example, that two phenyl groups of a diphenylamino group form a bond via a linking group as shown below. This explanation also applies to diheteroarylamino and arylheteroarylamino formed by aryl or heteroaryl.

[0076] [Chemical formula]

[0077] Specific examples of the linking group include >O, >N-R X , >C(-R X )2, >Si(-R X )2, >S, >CO, >CS, >SO, >SO2, and >Se. R X is independently alkyl, cycloalkyl, aryl, or heteroaryl, which may or may not be substituted with alkyl, cycloalkyl, aryl, or heteroaryl. Also, in >C(-R X )2 and >Si(-R X )2, R X may be bonded via a single bond or a linking group X Y to form a ring. Examples of X Y include >O, >N-R Y , >C(-R Y )2, >Si(-R Y )2, >S, >CO, >CS, >SO, >SO2, and >Se. R Y is independently alkyl, cycloalkyl, aryl, or heteroaryl, which may be substituted with alkyl, cycloalkyl, aryl, or heteroaryl. However, when X Y is >C(-R Y )2 and >Si(-RY ) In the case of 2, the two Rs Y do not combine to form a further ring. Further, examples of the linking group include alkenylene. Any at least one hydrogen of alkenylene is each independently unsubstituted or substituted with R X and R X are each independently alkyl, cycloalkyl, substituted silyl, aryl and heteroaryl, and at least one hydrogen of these is substituted or unsubstituted with alkyl (particularly tertiary alkyl as described later), cycloalkyl, substituted silyl, aryl.

[0078] In addition, when simply described as "diaryl amino", "diheteroaryl amino" or "aryl heteroaryl amino" in this specification, unless otherwise specified, it is assumed that the descriptions of "two aryls are bonded or not bonded via a linking group", "two heteroaryls are bonded or not bonded via a linking group" and "aryl and heteroaryl are bonded or not bonded via a linking group" are added respectively.

[0079] The first substituent, a substituted or unsubstituted "aryl", a substituted or unsubstituted "heteroaryl", a substituted or unsubstituted "diaryl amino", a substituted or unsubstituted "diheteroaryl amino", a substituted or unsubstituted "aryl heteroaryl amino", a substituted or unsubstituted "diaryl boryl", a substituted or unsubstituted "alkyl", a substituted or unsubstituted "alkenyl", a substituted or unsubstituted "cycloalkyl", a substituted or unsubstituted "alkoxy", a substituted or unsubstituted "aryloxy", a substituted or unsubstituted "arylthio", or a "substituted silyl", as described as substituted or unsubstituted, at least one hydrogen in them may be substituted with a second substituent. Preferred examples of this second substituent include aryl, heteroaryl, alkyl, cycloalkyl, or substituted silyl, and specific examples thereof can be referred to the description in this specification. Unless otherwise specified, this description can also be referred to in other "substituted or unsubstituted" phrases in this specification. Further, for aryl and heteroaryl as the second substituent, structures in which at least one hydrogen in them is substituted with aryl such as phenyl (specific examples are the groups described above), alkyl such as methyl, t-butyl (specific examples are the groups described above), or cycloalkyl such as cyclohexyl (specific examples are the groups described above) are also included in aryl and heteroaryl as the second substituent. As an example, when the second substituent is carbazolyl, carbazolyl in which at least one hydrogen at the 9-position is substituted with aryl such as phenyl, alkyl such as methyl, or cycloalkyl such as cyclohexyl is also included in heteroaryl as the second substituent. It should be noted that the two aryls of the "diaryl amino" are not bonded to each other or are bonded via a linking group, the two heteroaryls of the "diheteroaryl amino" are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the "aryl heteroaryl amino" are not bonded to each other or are bonded via a linking group, and the two aryls of the "diaryl boryl" are not bonded to each other or are bonded via a linking group.

[0080] The emission wavelength can be adjusted by the steric hindrance, electron-donating property, and electron-withdrawing property of the structure of the first substituent. Preferably, it is a group represented by the following structural formula, more preferably methyl, t-butyl, t-amyl, t-octyl, neopentyl, adamantyl, 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, and even 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, and 3,6-di-t-butylcarbazolyl. From the viewpoint of ease of synthesis, a larger steric hindrance is preferable for selective synthesis. Specifically, t-butyl, t-amyl, t-octyl, adamantyl, 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 preferable.

[0081] In the following structural formula, "Me" represents methyl, "tBu" represents t-butyl, "tAm" represents t-amyl, "tOct" represents t-octyl, and * represents the bonding position.

Chemical formula

[0082]

Chemical formula

[0083]

Chemical formula

[0084]

Chem.

[0085]

Chem.

[0086]

Chem.

[0087]

Chem.

[0088]

Chem.

[0089]

Chem.

[0090]

Chem.

[0091]

Chem.

[0092] [Chemistry]

[0093] [Chemistry]

[0094] The polycyclic aromatic compound having a structure composed of one or more structural units represented by the formula (1A-1) preferably has a structure containing at least one of a tertiary-alkyl (such as t-butyl or t-amyl), neopentyl or adamantyl represented by the above formula (tR), and more preferably contains a tertiary-alkyl (such as t-butyl or t-amyl) represented by the formula (tR). This is because the bulky substituent increases the intermolecular distance, thereby improving the luminescence quantum yield (PLQY). Further, as the substituent, diarylamino is more preferable. Furthermore, diarylamino substituted with a group of the formula (tR), carbazolyl substituted with a group of the formula (tR) (preferably, N-carbazolyl) or benzocarbazolyl substituted with a group of the formula (tR) (preferably, N-benzocarbazolyl) is also preferable. Examples of the substitution form of the group of the formula (tR) for diarylamino, carbazolyl and benzocarbazolyl include those in which some or all of the hydrogens of the aryl ring or benzene ring in these groups are substituted with the group of the formula (tR). Note that the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group.

[0095] Y 1is B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R, where R of the Si-R and the Ge-R is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl. Y 1 As Y, B, P, P=O, and P=S are preferable, B and P=O are more preferable, and B is most preferable.

[0096] n, m, q, and r are each independently 0 or 1. When it is 0, the carbon atom bonded to L 1 , L 2 , L 3 or L 4 is substituted with hydrogen or a substituent (or R 1 described later), but it is preferably substituted with hydrogen in all cases. When it is 1, it means that L 1 , L 2 , L 3 , and L 4 are directly bonded. Specifically, when n, q, and r are 1 and m is 0, taking formula (1A-1) as an example, it is as follows. This explanation applies to the preferable forms of formula (1A-1) unless otherwise specified. And, it is preferable that n + m = 1, and q + r is not 0 but q + r = 1.

Chemical formula

[0097] L 1 , L 2 , L 3 , and L 4is, independently of one another, a single bond, a substituted or unsubstituted arylene, a substituted or unsubstituted heteroarylene, a substituted or unsubstituted alkylene, a substituted or unsubstituted cycloalkylene, a substituted or unsubstituted alkenylene, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where R of the >N-R, R of the >Si(-R)2, and R of the >C(-R)2 are each independently hydrogen, a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl, or a substituted or unsubstituted cycloalkyl, and the two Rs of the >Si(-R)2 and the >C(-R)2 do not form a ring together or form a ring, and at least one of R of the >N-R, R of the >C(-R)2, and R of the >Si(-R)2 is each independently bonded or not bonded to at least one of the A1 ring to the A5 ring via a single bond or a linking group. "Arylene", "heteroarylene", "alkylene", "cycloalkylene" and "alkenylene" are each a divalent group obtained by removing one hydrogen from "aryl", "heteroaryl", "alkyl", "cycloalkyl" and "alkenyl", respectively, and the preferred ranges thereof can also be referred to accordingly.

[0098] L 1 and L 2Preferably, it is a substituted or unsubstituted arylene, a substituted or unsubstituted heteroarylene, or a substituted or unsubstituted alkenylene, more preferably a substituted or unsubstituted arylene or a substituted or unsubstituted alkenylene. As the arylene, phenylene or naphthylene is preferable. As the heteroarylene, benzothiophenylene, benzofuranylene, indolylene, dibenzothiophenylene, dibenzofuranylene, or carbazolylene is preferable. Regarding the substituent, the description of "substituted or unsubstituted" in this specification can be referred to. The arylene and heteroarylene are preferably unsubstituted or at least one hydrogen is substituted with alkyl (especially tertiary-alkyl such as t-butyl or t-amyl), cycloalkyl, diarylamino, or substituted silyl, and are preferably unsubstituted or at least one hydrogen is substituted with alkyl (especially tertiary-alkyl such as t-butyl or t-amyl), cycloalkyl, or diarylamino. The alkenylene is preferably in an unsubstituted form or a form in which at least one hydrogen is substituted with alkyl or aryl. Note that the two aryls of the diarylamino may or may not be bonded via a linking group, and at least one hydrogen of the two aryls may be substituted with tertiary-alkyl. L 3 , and L 4 As, a single bond is more preferable.

[0099] The polycyclic aromatic compound of the present invention is a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1A-1). Examples of the polycyclic aromatic compound having a structure composed of one of the above structural units include polycyclic aromatic compounds represented by the formula described above as the structural unit represented by formula (1A-1). Examples of the polycyclic aromatic compound having a structure composed of two or more structural units represented by formula (1A-1) include compounds corresponding to multimers of polycyclic aromatic compounds represented by the formula described above as the structural unit represented by formula (1A-1). The multimer is preferably a dimer to hexamer, more preferably a dimer to trimer, and particularly preferably a dimer. The multimer may be in a form having a plurality of the above unit structures in one compound, and may be in a form bonded so as to share any ring (in the case of being described by formula (1), ring A1, ring A2, ring A3, ring A4, and ring A5) included in the above structural unit by a plurality of unit structures, or may be in a form bonded so that any rings (in the case of being described by formula (1A-1), ring A1, ring A2, ring A3, ring A4, and ring A5) included in the above unit structure are condensed with each other. Further, the above unit structure may be in a form in which a plurality of them are bonded by a linking group such as a single bond, an alkylene having 1 to 3 carbon atoms, a phenylene, or a naphthylene. Among these, a form bonded so as to share a ring is more preferable. This description is also applicable to the preferable form of the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1A-1) described later.

[0100] The polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1A-1) and its desirable form described later may be condensed with at least one cycloalkane.

[0101] The cycloalkane may be a cycloalkane having 3 to 24 carbon atoms. At least one hydrogen in the cycloalkane at this time is not substituted or is substituted with an aryl having 6 to 30 carbon atoms, a heteroaryl having 2 to 30 carbon atoms, an alkyl having 1 to 24 carbon atoms, or a cycloalkyl having 3 to 24 carbon atoms, and at least one -CH2- in the cycloalkane may be substituted with -O- or -S-.

[0102] When at least one selected from the group consisting of an aryl ring and a heteroaryl ring in a structure composed of one or more structural units represented by formula (1A-1) is condensed with at least one cycloalkane, the at least one cycloalkane is a cycloalkane having 3 to 20 carbon atoms, and it is preferable that at least one hydrogen in the cycloalkane is a cycloalkane that may be substituted with an aryl having 6 to 16 carbon atoms, a heteroaryl having 2 to 22 carbon atoms, an alkyl having 1 to 12 carbon atoms, or a cycloalkyl having 3 to 16 carbon atoms.

[0103] Examples of the "cycloalkane" include cycloalkanes having 3 to 24 carbon atoms, cycloalkanes having 3 to 20 carbon atoms, cycloalkanes having 3 to 16 carbon atoms, cycloalkanes having 3 to 14 carbon atoms, cycloalkanes having 5 to 10 carbon atoms, cycloalkanes having 5 to 8 carbon atoms, cycloalkanes having 5 to 6 carbon atoms, and cycloalkanes having 5 carbon atoms.

[0104] Specific examples of the cycloalkane include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornene, bicyclo[1.1.0]butane, bicyclo[1.1.1]pentane, 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, diamantane, decahydronaphthalene, and decahydroazulene, as well as their C1-C5 alkyl (especially methyl) substituents, halogen (especially fluorine) substituents, and deuterium substituents.

[0105] Among these, for example, a structure in which at least one hydrogen at the α-position carbon of a cycloalkane (in a cycloalkyl condensed to an aryl ring or a heteroaryl ring, the carbon at the position adjacent to the carbon of the condensation site) is substituted as shown in the following structural formula is preferable, a structure in which two hydrogens at the α-position carbon are substituted is more preferable, and a structure in which a total of four hydrogens at two α-position carbons are substituted is even more preferable. Examples of this 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 is preferable that a partial structure represented by the following formula (Z) is bonded to adjacent carbon atoms in the aryl ring or heteroaryl ring.

[0106]

Chemical formula

[0107] The number of cycloalkanes condensed to one aryl ring or heteroaryl ring is preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. For example, examples of one or more cycloalkanes condensed to one benzene ring (phenyl) are shown below. * represents the bonding position, and that position may be any of the carbons that constitute the benzene ring and do not constitute the cycloalkane. Cycloalkanes condensed as in formula (Cy-1-4) and formula (Cy-2-4) may be condensed with each other. Even when the ring (group) to be condensed is another aryl ring or heteroaryl ring other than the benzene ring (phenyl), or when the cycloalkane to be condensed is a cycloalkane other than cyclopentane or cyclohexane, the same applies.

[0108]

Chemical formula

[0109] At least one -CH2- in the cycloalkane may be replaced by -O- or -S-. For example, examples in which one or more -CH2- in a cycloalkane condensed to one benzene ring (phenyl) are replaced by -O- are shown below. The same applies even when the ring (group) to be condensed is another aromatic ring or heteroaromatic ring other than the benzene ring (phenyl), or even when the cycloalkane to be condensed is a cycloalkane other than cyclopentane or cyclohexane.

[0110]

Chemical formula

[0111] At least one hydrogen in the cycloalkane is unsubstituted or substituted, and examples of such substituents include aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl, alkyl, alkenyl, cycloalkyl, alkoxy, aryloxy, arylthio, substituted silyl, deuterium, cyano, or halogen. Details of these can cite the description of the first substituent mentioned above. Note that the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, and the two aryls of the diarylboryl are not bonded to each other or are bonded via a linking group. Among these substituents, alkyl (for example, alkyl having 1 to 6 carbon atoms), cycloalkyl (for example, cycloalkyl having 3 to 14 carbon atoms), halogen (for example, fluorine), and deuterium are preferable. Also, when cycloalkyl substitutes, a substitution form that forms a spiro structure may be used, and an example of this is shown below.

[0112]

Chemical formula

[0113] As a form of cycloalkane condensation, first, there is a form in which the aryl ring and heteroaryl ring in each of the A1 ring to A5 rings in a polycyclic aromatic compound having a structure composed of one or more structural units represented by the formula (1A-1) are condensed with a cycloalkane.

[0114] As another form of cycloalkane condensation, there are examples in which a polycyclic aromatic compound having a structure composed of one or more structural units represented by the formula (1A-1) has a diarylamino condensed with a cycloalkane condensed to this aryl moiety, a carbazolyl condensed with a cycloalkane (condensed to the benzene ring moiety), or a benzocarbazolyl condensed with a cycloalkane (condensed to the benzene ring moiety). Also, forms in which an arylene, heteroarylene, or alkenylene such as L 1 , L 2 , L 3 , and L 4 are condensed with a cycloalkane are also included, and examples in which at least one R of N-R, >C(-R)2, or >Si(-R)2 is an aryl condensed with a cycloalkane or a heteroaryl condensed with a cycloalkane are also included. For the "diarylamino", the groups described as the above "first substituent" can be mentioned. Note that the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group.

[0115] Note that by introducing a cycloalkane structure into the polycyclic aromatic compound of the present invention, a decrease in the melting point and sublimation temperature can be expected. 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, purification can be carried out at a relatively low temperature, thus avoiding thermal decomposition of the material. The same applies to the vacuum deposition process, which is a powerful means for manufacturing organic devices such as organic EL elements. Since the process can be carried out at a relatively low temperature, thermal decomposition of the material can be avoided, and as a result, high-performance organic devices can be obtained. In addition, since the introduction of the cycloalkane structure improves the solubility in organic solvents, it can also be applied to the fabrication of elements using a coating process. However, the present invention is not particularly limited to these principles.

[0116] In the polycyclic aromatic compound composed of one or more structural units represented by formula (1A-1) and the hydrogen in its preferred forms described later, all or part of it may be deuterium, cyano, or halogen. The halogen is fluorine, chlorine, bromine, or iodine, preferably fluorine, chlorine, or bromine, more preferably fluorine or chlorine, and even more preferably fluorine. Also, from the perspective of durability, it is also preferable that all or part of the hydrogen in the aromatic ring part of the structure composed of one or more structural units represented by formula (1A-1) is deuterated, and it is more preferable that all of the aromatic ring part is deuterated. L 1 、L 2 、L 3 Or L 4 The hydrogen substituted on the alkenylene which is, and it is most preferable that all of the aromatic ring part is deuterated.

[0117] For example, in the structure composed of one or more structural units represented by formula (1A-1), the aryl ring, heteroaryl ring, cycloalkyl ring, or cycloheteroalkyl ring as the A1 ring, A2 ring, A3 ring, A4 ring, and A5 ring, or the substituents on the A1 ring, A2 ring, A3 ring, A4 ring, and A5 ring, or L 1 、L 2 、L3 and L 4 As, substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, substituted or unsubstituted alkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted alkenylene, >N-R, >C(-R)2, >Si(-R)2 of arylene, heteroarylene, alkylene, cycloalkylene, alkenylene, >N-R of R, >Si(-R)2 of R, and the hydrogen in the R of the >C(-R)2 can be substituted with deuterium, cyano or halogen, among which the mode in which all or part of the hydrogen in the aromatic ring part of aryl, heteroaryl, arylene, heteroarylene is substituted with deuterium, cyano or halogen is preferably mentioned.

[0118] As a preferable example of the structural unit represented by the formula (1A-1), the structural unit represented by the following formula (1a-1) can be mentioned. Regarding the substituents in the formula (1a-1) and the structure of the contained rings and the preferable ranges, each description of the corresponding formula (1a-1) can be referred to.

[0119]

Chemical formula

[0120] In the formula (1a-1), Y 1 L 1 L 2 L 3 L 4 L 4 The definitions of n, m, q and r and their preferable ranges are synonymous with those in the formula (1A-1), respectively.

[0121] In the formula (1a-1), Z is, independently of each other, N or C-R 1 and the R of the C-R 1 of the R 1are each independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, with hydrogen, aryl, heteroaryl, alkyl, cycloalkyl, or diarylamino being preferred. At least one hydrogen in these is unsubstituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl. Also, R 1 is more preferably hydrogen, alkyl, cycloalkyl, or diarylamino, and the diarylamino is unsubstituted or substituted with alkyl or cycloalkyl. Note that the two aryls of the said diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the said diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the said arylheteroarylamino are not bonded to each other or are bonded via a linking group, and the two aryls of the said diarylboryl are not bonded to each other or are bonded via a linking group. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification.

[0122] In formula (1a-1), two adjacent Rs 1are not bonded to each other to form an aryl ring or a heteroaryl ring, or form an aryl ring or a heteroaryl ring, and at least one hydrogen of the formed aryl ring and the formed heteroaryl ring may each be substituted with aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboril, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, but hydrogen, aryl, heteroaryl, alkyl, cycloalkyl, or diarylamino is preferred, and at least one hydrogen in these may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl. Note that the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, and the two aryls of the diarylboril are not bonded to each other or are bonded via a linking group. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification.

[0123] Z is, independently of each other, N or C-R 1 or Z=Z is, independently of each other, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, but all are independently C-R 1It is preferably so. The Rs in the >N-R, the >C(-R)2, and the >Si(-R)2 are each independently hydrogen, aryl, heteroaryl, alkyl, or cycloalkyl, and when at least one hydrogen in these is substituted, it is preferably aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl. The two Rs in the >C(-R)2 and the >Si(-R)2 may or may not be bonded to each other to form a ring. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification.

[0124] For example, in the a2 ring in formula (1a-1), examples of the ring obtained by replacing the position of "Z=Z" with >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se include a cyclopentadiene ring, a pyrrole ring, a furan ring, a thiophene ring, etc. In the a2 ring or the like, an example where one Z=Z is >N-R, >O, >S, >C(-R)2 and the remaining Z is C-H is given. However, the forms that the a2 ring or the like can take are not limited to the following examples. As described above, since aromatic compounds have resonating structural formulas that are completely equivalent in organic chemistry, any possible resonating structural formula may be used as a basis.

[0125]

Chemical formula

[0126] L in formula (1A-1) 1 、L 2 、L 3 、and L 4 The above description that the R in at least one of >N-R, >Si(-R)2 and >C(-R)2 in L is or is not bonded to the A1 ring to A5 ring by a linking group or a single bond means that in formula (1a-1), "the R of the >N-R, the R of the >C(-R)2, and the R of at least one of the >Si(-R)2 are each independently the R in Z which is C-R Z where Z is Zcorresponds to the provision of "at least one of them, which is bonded or not bonded by -O-, -S-, -C(-R)2- or a single bond". Specifically, the above R is the a1 ring to a5 rings, and the spatially closest C-R in each ring Z is bonded or not bonded to Z which is Z .

[0127] In formula (1a-1) and its preferred forms, the number of rings (monocyclic) containing Z which is N is 0 to 4, preferably 0 to 3, more preferably 0 to 2, and particularly preferably 0 to 1. In formula (1a-1) and its preferred forms, it is also preferred that all Z are C-R Z is the case.

[0128] In formula (1a-1) and in the ring (monocyclic) containing Z which is N in its preferred forms, it is preferred that one or two of the plurality of Z are N. When two Z are N, it is preferred that the two N are not adjacent to each other. When the 6-membered ring is a ring containing Z which is N, a pyridine ring, a pyrimidine ring, a pyridazine ring, or a 1,2,3-triazine ring is preferred, and a pyridine ring or a pyrimidine ring is more preferred. When the 5-membered ring is a ring containing Z which is N, a thiazole ring or an oxazole ring is preferred.

[0129] Preferred examples of the structural unit represented by formula (1A-1) include the structural units represented by formula (1b-1) or formula (1b-2). Regarding the substituents and the structure of the rings contained in formula (1b-1) and formula (1b-2), and the preferred ranges, each description of the corresponding formula (1a-1) can be referred to.

Chemical formula

[0130] In formula (1b-1) and formula (1b-2), q and r are each independently 0 or 1. When it is 0, the carbon atom bonded to the divalent group in the parentheses is R 1 substituted, provided that q + r ≠ 0, but q + r = 1 is preferred. L3 , L 4 are each independently a single bond, an arylene, a heteroarylene or an alkenylene, and at least one hydrogen of these is substituted or unsubstituted with an alkyl, a cycloalkyl, a diarylamino, or a substituted silyl, and the two aryls of the diarylamino are bonded or not bonded via a linking group. L 3 and L 4 are preferably a single bond. In addition, regarding the definitions of Z and Y1 and their preferred ranges, each description of formula (1a-1) can be referred to.

[0131] Preferred examples of the structural unit represented by formula (1A-1) include the structural units represented by formula (1c-1), formula (1c-2), formula (1c-3), or formula (1c-4). Regarding the definitions of Z in formula (1c-1), formula (1c-2), formula (1c-3) and formula (1c-4) and their preferred ranges, each description of the corresponding formula (1a-1) can be referred to. [Chemical formula]

[0132] Preferred examples of the structural unit represented by formula (1A-1) include the structural units represented by formula (1d-1) or formula (1d-2). [Chemical formula]

[0133] In formula (1d-1) and formula (1d-2), R dEach is independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, preferably hydrogen, aryl, heteroaryl, alkyl, cycloalkyl, or diarylamino, or substituted silyl, more preferably hydrogen, alkyl, cycloalkyl, aryl or heteroaryl, and most preferably all are hydrogen. Further, at least one hydrogen in these is unsubstituted or substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl. Note that the two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group, and the two aryls of the diarylboryl are not bonded to each other or are bonded via a single bond or a linking group. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification. Note that for the definitions of the other symbols and the preferred ranges in Formula (1d-1) and Formula (1d-2), reference can be made to the respective explanations of Formula (1b-1) and Formula (1b-2).

[0134] Preferred examples of the structural unit represented by Formula (1A-1) include structural units represented by Formula (1e-1), Formula (1e-2), Formula (1e-3) or Formula (1e-4). For the definitions of the respective symbols and the preferred ranges, reference can be made to the respective explanations of Formula (1d-1) and Formula (1d-2).

Chemical formula

[0135] Preferred examples of the structural unit represented by formula (1A-1) include structural units represented by formula (1f-1) or formula (1f-2).

Chemical formula

[0136] In formula (1f-1) or formula (1f-2), x is an integer from 1 to 3. Taking formula (1f-1) as an example, the cases where x is 1 or 2 are shown.

Chemical formula

[0137] When x is 2 or 3, two or three Es are consecutive. As they are defined as "independent" as described later, two or three Es may be the same or different. Also, when x is 3, two Es may be the same and one E may be different. This explanation applies to the preferred forms of formula (1f-1) or formula (1f-2) described later, unless otherwise specified.

[0138] In formula (1f-1) or formula (1f-2), each A is independently >(CR)-, and R in the >(CR)- is hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl. It is more preferable that R is hydrogen or alkyl. Also, for A's >(CR)- bonded to N and L1 to L4 when the subscript (n, m, q, and r) in the parentheses is 1, it is preferable that R is alkyl. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification.

[0139] In formula (1f-1) or formula (1f-2), when the subscript in the parentheses of the adjacent L of A 3 or L 4 is 1, L 3 or L 4 is bonded. When the subscript is 0, the carbon atom of >(CR)- which is A is bonded to L3 or L 4 independently on each carbon atom of the f3 ring or the f4 ring that was combined with, R 1 will be substituted. When this is shown by, for example, formula (1f-1), it becomes as follows. In the following, R represents R of (CR)- where R is A. This explanation is also applicable to the preferred forms of formula (1f-1) or formula (1f-2) described later, unless otherwise specified. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification. [Chemical formula]

[0140] In formula (1f-1) or formula (1f-2), E is independently >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se. The R of >N-R, the R of >Si(-R)2, and the R of >C(-R)2 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl. The two Rs of all >Si(-R)2 and the two Rs of >C(-R)2 do not combine with each other to form a ring, or form a ring, but preferably, E is independently >O, >N-R, >S, or >C(-R)2, and most preferably, all Es are independently >C(-R)2. And it is more preferable that all Rs of >C(-R)2 are hydrogen. This explanation is also applicable to the preferred forms of formula (1f-1) or formula (1f-2) described later, unless otherwise specified.

[0141] Regarding other symbols in formula (1f-1) or formula (1f-2) and their preferred ranges, reference can be made to the explanation in formula (1a-1). Also, for details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification.

[0142] Preferable examples of the structural unit represented by formula (1f-1) or formula (1f-2) include a structural unit represented by formula (1g-1) or formula (1g-2).

Chemical formula

[0143] Regarding the definitions of A, E, and x in formula (1g-1) or formula (1g-2) and their preferable ranges, reference can be made to the descriptions in formula (1f-1) and formula (1f-2). Also, regarding the definitions of Z, Y 1 , L 3 , L 4 , r, and q and their preferable ranges, reference can be made to the descriptions of formula (1b-1) and formula (1b-2).

[0144] Preferable examples of the structural unit represented by formula (1f-1) or formula (1f-2) include a structural unit represented by formula (1h-1), formula (1h-2), formula (1h-3), or formula (1h-4).

Chemical formula

[0145] In formula (1h-1), formula (1h-2), formula (1h-3), and formula (1h-4), regarding the definitions of A, E, and x and their preferable ranges, reference can be made to the descriptions in formula (1f-1) and formula (1f-2). Also, regarding the definition of Z and its preferable range, reference can be made to the descriptions of formula (1b-1) and formula (1b-2).

[0146] Preferable examples of the structural unit represented by formula (1f-1) or formula (1f-2) include a structural unit represented by formula (1i-1) or formula (1i-2).

Chemical formula

[0147] In formula (1i-1) or formula (1i-2), R dFor the definitions and their preferred ranges, reference can be made to the description of Formula (1d-1) or Formula (1d-2). For other symbols and their preferred ranges, reference can be made to the description in Formula (1b-1) or Formula (1b-2).

[0148] Preferred examples of the structural unit represented by Formula (1f-1) or Formula (1f-2) include structural units represented by Formula (1k-1), Formula (1k-2), Formula (1k-3) or Formula (1k-4). [Chemical formula]

[0149] In Formula (1k-1), Formula (1k-2), Formula (1k-3) or Formula (1k-4), R d For the definitions and their preferred ranges, reference can be made to the description of Formula (1d-1) or Formula (1d-2). For the definition of Z and its preferred ranges, reference can be made to the description in Formula (1b-1) and Formula (1b-2).

[0150] Preferred examples of the polycyclic aromatic compound having a structure composed of two structural units represented by Formula (1a-1) include Formula (1a-d-1), Formula (1a-d-2), Formula (1a-d-3) and Formula (1a-d-4). These structures are dimer structures sharing an a8 ring respectively. TIFF0007693169000054.tif145161

[0151] In Formula (1a-d-1), Formula (1a-d-2), Formula (1a-d-3) and Formula (1a-d-4), L 5 , L 6 , L 7 , L 8 , L 9 , L 10 , L 11 and L 12Each is independently a single bond, a substituted or unsubstituted arylene, a substituted or unsubstituted heteroarylene, a substituted or unsubstituted alkylene, a substituted or unsubstituted cycloalkylene, a substituted or unsubstituted alkenylene, >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where R of >N-R, R of >Si(-R)2, and R of >C(-R)2 are each independently hydrogen, a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl, or a substituted or unsubstituted cycloalkyl, and the two Rs of >Si(-R)2 and the two Rs of >C(-R)2 may be bonded to each other to form a ring. Among these, a single bond, a substituted or unsubstituted arylene (preferably phenylene or naphthylene), or a substituted or unsubstituted heteroarylene (preferably benzothiophenylene, benzofuranylene, indolylene, dibenzothiophenylene, dibenzofuranylene, or carbazolylene) is preferred, L 5 ~L 12 At least one of is a substituted or unsubstituted arylene, a substituted or unsubstituted heteroarylene, or a substituted or unsubstituted alkenylene (in each case, the subscript in parentheses is 1). Also, d + e + f + h + s + t + w + w ≠ 0. Y 1 And Z can apply the definition and preferred range of formula (1a-1), but it is preferred that all of Z are C-R 1 and it is preferred that Y 1 is B. For details of the substituents listed here and their preferred ranges, reference can be made to the description in this specification.

[0152] Preferable examples of the polycyclic aromatic compound having a structure composed of two structural units represented by Formula (1c-1) to Formula (1c-4) include, for example, Formula (1c-d-1), Formula (1c-d-2), Formula (1c-d-3), Formula (1c-d-4), Formula (1c-d-5), Formula (1c-d-6), Formula (1c-d-7), Formula (1c-d-8), Formula (1c-d-9), Formula (1c-d-10), Formula (1c-d-11), Formula (1c-d-12), Formula (1c-d-13), Formula (1c-d-14), Formula (1c-d-15), Formula (1c-d-16), Formula (1c-d-17), Formula (1c-d-18), or Formula (1c-d-19). Preferable examples of the polycyclic aromatic compound having a structure composed of two structural units represented by Formula (1e-1) to Formula (1e-4) include, for example, Formula (1e-d-1), Formula (1e-d-2), Formula (1e-d-3), Formula (1e-d-4), Formula (1e-d-5), Formula (1e-d-6), Formula (1e-d-7), Formula (1e-d-8), Formula (1e-d-9), Formula (1e-d-10), Formula (1e-d-11), Formula (1e-d-12), (1e-d-13), Formula (1e-d-14), Formula (1e-d-15), Formula (1e-d-16), Formula (1e-d-17), Formula (1e-d-18), or Formula (1e-d-19). These structures are each a dimer structure sharing a c11 ring or an e11 ring. The definitions and preferable ranges of Formula (1c-1) to Formula (1c-4) and Formula (1e-1) to Formula (1e-4) are applicable to Z respectively.

[0153]

Chem.

[0154]

Chem.

[0155]

Chem.

[0156]

Chem.

[0157]

Chem.

[0158]

Chem.

[0159] As further specific examples of the polycyclic aromatic compound having a structure composed of one or more structural units represented by the formula (1A-1) of the present invention, the following compounds can be mentioned. In the following structural formulas, "Me" represents methyl, "tBu" represents t-butyl, and "D" represents deuterium. Note that the following structure is an example.

[0160]

Chem.

[0161] [Chemical]

[0162] [Chemical]

[0163] [Chemical]

[0164] [Chemical]

[0165] The polycyclic aromatic compound of the present invention can be produced by the following procedure.

[0166] [Method for Producing Polycyclic Aromatic Compound] A polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1A-1) can basically be produced by first bonding the A1 ring to the A5 ring with a linking group (L 1 ~L 4 , and a group containing a nitrogen atom) to produce an intermediate (first reaction), and then bonding the A2 ring and the A4 ring with a linking group (Y 1 -containing group) to produce the final product (second reaction). In the first reaction, for example, if it is an etherification reaction, general reactions such as nucleophilic substitution reaction and Ullmann reaction can be used, and if it is an amination reaction, general reactions such as Buchwald-Hartwig reaction can be used. Also, in the second reaction, a tandem hetero Friedel-Crafts reaction (successive aromatic electrophilic substitution reaction, the same hereinafter) can be used. By using a raw material having a desired condensed ring or adding a step of condensing the ring somewhere in the reaction process, a compound having a condensed ring can be produced. Also, for a polycyclic aromatic compound having a structure composed of two or more structural units, the corresponding intermediate can be produced in the above first reaction, and it can be bonded with a linking group (Y 1 -containing group) in the second reaction. In this case, Y1 The reagents necessary for the introduction of a group containing (such as boron sesquifluoride), Y to be introduced 1 may be adjusted according to the number of

[0167] <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 of the following steps, reference can be made to the description in International Publication No. 2015 / 102118.

[0168] A reaction step of metallating a halogen atom (Hal) between nitrogen atoms in the following Intermediate-1 using an organic alkali compound, and Y 1 halide of Y, Y 1 aminohalide of Y, Y 1 alkoxide of Y and Y 1 A reaction step of exchanging the metal and Y using a reagent selected from the group consisting of aryloxides of Y 1 and, a reaction step of bonding the B ring and the C ring with the Y 1 by a continuous aromatic electrophilic substitution reaction using a Brønsted base is described below.

[0169]

Chemical formula

[0170] <Production method via Intermediate-2> The polycyclic aromatic compound of the present invention can also be produced by a production method including the following steps. For each of the following steps, reference can be made to the description in International Publication No. 2015 / 102118.

[0171] A reaction step of metallating a hydrogen atom (H) between nitrogen atoms in the following Intermediate-2 using an organic alkali compound, and Y 1 halide of Y, Y 1 aminohalide of Y, Y 1 alkoxide of Y and Y 1 A reaction step of exchanging the metal and Y using a reagent selected from the group consisting of aryloxides of Y 1A reaction step of exchanging with, and a continuous aromatic electrophilic substitution reaction using a Bronsted base to form the above Y 1 The reaction including the reaction step of bonding the B ring and the C ring with Y is described below. Also, the reaction step of metalating a hydrogen atom (H) using an organic alkali compound as described in Journal of The American Chemistry, 2018, 140, 1195 - 1198, Angewandte Chemie International Edition 2021, 60, 2882 - 2886, or Nature Photonics 2019, 13, 678, etc. can be omitted, and a method (one-shot method) of directly reacting with a halide of Y (such as boron tribromide) can be used. In this case, after reacting with a halide of Y (such as boron tribromide), or simultaneously, a base such as an amine may be used. 1 1

[0172]

Chemical formula

[0173] Examples of the metalating reagent used in the halogen-metal exchange reaction in the scheme described so far include alkyllithiums such as methyllithium, n-butyllithium, sec-butyllithium, t-butyllithium, isopropylmagnesium chloride, isopropylmagnesium bromide, phenylmagnesium chloride, phenylmagnesium bromide, and the lithium chloride complex of isopropylmagnesium chloride known as the turbogrinard reagent.

[0174] In addition, examples of the metalating reagent used in the orthometalation reaction in the scheme described so far include organic alkali compounds such as lithium diisopropylamide, lithium tetramethylpiperidide, lithium hexamethyldisilazide, potassium hexamethyldisilazide, lithium tetramethylpiperidinylmagnesium chloride·lithium chloride complex, and lithium tri-n-butylmagnesate in addition to the above reagents. ​​

[0175] Furthermore, examples of additives that accelerate the reaction when using alkyllithium as a metalation reagent include N,N,N’,N’-tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, N,N-dimethylpropyleneurea, and the like.

[0176] In addition, examples of Lewis acids used in the schemes described so far include AlCl3, AlBr3, AlF3, BF3·OEt2, BCl3, BBr3, GaCl3, GaBr3, InCl3, InBr3, In(OTf)3, SnCl4, SnBr4, AgOTf, ScCl3, Sc(OTf)3, ZnCl2, ZnBr2, Zn(OTf)2, MgCl2, MgBr2, Mg(OTf)2, LiOTf, NaOTf, KOTf, Me3SiOTf, Cu(OTf)2, CuCl2, YCl3, Y(OTf)3, TiCl4, TiBr4, ZrCl4, ZrBr4, FeCl3, FeBr3, CoCl3, CoBr3, and the like. Further, those obtained by supporting these Lewis acids on a solid can also be used in the same manner.

[0177] In addition, examples of Bronsted acids used in the schemes described so far include p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, fluorosulfonic acid, carborane acid, trifluoroacetic acid, (trifluoromethanesulfonyl)imide, tris(trifluoromethanesulfonyl)methane, hydrogen chloride, hydrogen bromide, hydrogen fluoride, and the like. Further, examples of solid Bronsted acids include Amberlyst (trade name: Dow Chemical), Nafion (trade name: DuPont), zeolite, Teicacure (trade name: Teica Corporation), and the like.

[0178] In addition, examples of amines that may be added in the schemes described so far 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.

[0179] In addition, solvents used in the schemes described so far 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.

[0180] Here, an example where Y 1 is B has been described. However, by appropriately changing the raw materials, compounds in which Y 1 is P, P=O, P=S, Al, Ga, As, Si-R or Ge-R can also be synthesized.

[0181] As the halide of Y to be used 1 where Y 1 is B, boron trichloride, boron tribromide, and boron triiodide can be mentioned.

[0182] In the above scheme, a Bronsted base or a Lewis acid may be used to promote the tandem hetero Friedel-Crafts reaction. However, when using halides of Y 1 such as trifluorides of Y 1 trichlorides of Y 1 tribromides of Y 1 triiodides of Y 1 acids such as hydrogen fluoride, hydrogen chloride, hydrogen bromide, and hydrogen iodide are generated as the aromatic electrophilic substitution reaction proceeds. Therefore, the use of a Bronsted base that captures the acid is effective. On the other hand, when using aminated halides of Y 1 or alkoxides of Y 1 amines and alcohols are generated as the aromatic electrophilic substitution reaction proceeds. Therefore, in many cases, it is not necessary to use a Bronsted base. However, since the leaving ability of amino and alkoxy is low, the use of a Lewis acid that promotes the elimination is effective.

[0183] In addition, the polycyclic aromatic compounds of the present invention include compounds in which at least some hydrogen atoms are substituted with deuterium or cyano, and compounds substituted with halogens such as fluorine and chlorine. Such compounds can be synthesized in the same manner as described above by using raw materials in which the desired positions are deuterated, cyanated, fluorinated, or chlorinated. Further, deuterium compounds and halogen compounds can also be obtained by halogenating or deuterating precursors of the target halogenated compounds and deuterated compounds, respectively.

[0184] <Organic device> The polycyclic aromatic compounds of the present invention can be used as materials for organic devices. Examples of organic devices include organic electroluminescent elements, organic field effect transistors, and organic thin film solar cells, etc., and it is preferably a material for organic electroluminescent elements.

[0185] <Organic electroluminescent element> <Structure of organic electroluminescent element> 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, a hole transport layer 104 provided on the hole injection layer 103, a light emitting layer 105 provided on the hole transport layer 104, an electron transport layer 106 provided on the light emitting layer 105, an electron injection layer 107 provided on the electron transport layer 106, and a cathode 108 provided on the electron injection layer 107.

[0186] Note that the organic EL element 100 may have a configuration in which the manufacturing order is reversed, for example, including a substrate 101, a cathode 108 provided on the substrate 101, an electron injection layer 107 provided on the cathode 108, an electron transport layer 106 provided on the electron injection layer 107, a light emitting layer 105 provided on the electron transport layer 106, a hole transport layer 104 provided on the light emitting layer 105, a hole injection layer 103 provided on the hole transport layer 104, and an anode 102 provided on the hole injection layer 103.

[0187] Not all of the above layers are essential. With the minimum structural unit being composed of an anode 102, a light-emitting layer 105, and a cathode 108, the hole injection layer 103, the hole transport layer 104, the electron transport layer 106, and the electron injection layer 107 are optional layers. Also, each of the above layers may consist of a single layer or multiple layers.

[0188] As the modes of the layers constituting the organic EL element, in addition to the above-described mode of "substrate / anode / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode", there may also be the modes of "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 / light-emitting layer / electron transport layer / electron injection layer / cathode", "substrate / anode / hole transport layer / light-emitting layer / electron injection layer / cathode", "substrate / anode / hole transport layer / light-emitting layer / electron transport layer / cathode", "substrate / anode / hole injection layer / light-emitting layer / electron injection layer / cathode", "substrate / anode / hole injection layer / light-emitting layer / electron transport layer / cathode", "substrate / anode / light-emitting layer / electron transport layer / cathode", "substrate / anode / light-emitting layer / electron injection layer / cathode".

[0189] <Light-Emitting Layer in Organic Electroluminescent Element> 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 electrodes to which an electric field is applied. As the material for forming the light-emitting layer 105, any compound (light-emitting compound) that is excited by the recombination of holes and electrons to emit light may be used, and it is preferable that a stable thin-film shape can be formed and a strong light-emitting (fluorescent) efficiency is exhibited in the solid state. The polycyclic aromatic compound of the present invention can be used as a material for the light-emitting layer, and may be used as a dopant material or a host material, but is preferably used as a material for the light-emitting layer, and more preferably used as a dopant material.

[0190] Note that as the dopant, there is an example of using an assisting dopant and an emitting dopant in combination as described later. However, in this specification, when simply described as "dopant", it refers to an emitting dopant, that is, a dopant that emits light by itself.

[0191] The light-emitting layer may be a single layer or a plurality of layers, and each is formed of a light-emitting layer material (host material, dopant material). The host material and the dopant material may each be of one type or a plurality of combinations. The dopant material may be contained in the whole host material or partially contained. As the doping method, it can be formed by a co-evaporation method with the host material, but it may be co-evaporated after mixing with the host material in advance.

[0192] The amount of the host material used varies depending on the type of the host material, and may be determined according to the characteristics of the host material. The standard amount of the host material used is preferably 50 to 99.999% by mass of the total light-emitting layer material, more preferably 80 to 99.95% by mass, and still more preferably 90 to 99.9% by mass.

[0193] The amount of the dopant material used varies depending on the type of the dopant material, and it may be determined according to the characteristics of the dopant material. The standard amount of the dopant used is preferably 0.001 to 50% by mass, more preferably 0.05 to 20% by mass, and still more preferably 0.1 to 10% by mass of the entire material for the light-emitting layer. If it is within the above range, for example, it is preferable in that the concentration quenching phenomenon can be prevented.

[0194] <Host material> Examples of the host material include condensed ring derivatives such as anthracene, pyrene, dibenzocrisene or fluorene, which have been known as light emitters, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, fluorene derivatives, benzofluorene derivatives, and dibenzocrisene-based compounds.

[0195] In addition, as the host material, for example, a compound represented by any of the following formulas (H1), (H2) and (H3) can be used.

Chemical formula

[0196] In formulas (H1), (H2) and (H3), L 1is an arylene having 6 to 24 carbon atoms, a heteroarylene having 2 to 24 carbon atoms, a heteroarylene arylene having 6 to 24 carbon atoms, and an arylene heteroarylene arylene having 6 to 24 carbon atoms. An arylene having 6 to 16 carbon atoms is preferred, an arylene having 6 to 12 carbon atoms is more preferred, and an arylene having 6 to 10 carbon atoms is particularly preferred. Specifically, divalent groups such as benzene ring, biphenyl ring, terphenyl ring, and fluorene ring can be mentioned. As the heteroarylene, a heteroarylene having 2 to 24 carbon atoms is preferred, a heteroarylene having 2 to 20 carbon atoms is more preferred, a heteroarylene having 2 to 15 carbon atoms is further preferred, and a heteroarylene having 2 to 10 carbon atoms is particularly preferred. Specifically, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, oxadiazole ring, thiadiazole ring, triazole ring, tetrazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyridazine ring, pyrazine ring, triazine ring, indole ring, isoindole ring, 1H-indazole ring, benzimidazole ring, benzoxazole ring, benzothiazole ring, 1H-benzotriazole ring, quinoline ring, isoquinoline ring, cinnoline ring, quinazoline ring, quinoxaline ring, phthalazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, acridine ring, phenoxathiin ring, phenoxazine ring, phenothiazine ring, phenazine ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, furazan ring, oxadiazole ring, and thianthrene ring and other divalent groups can be mentioned. At least one hydrogen in the compound represented by the above formulas may be substituted with an alkyl having 1 to 6 carbon atoms, cyano, halogen, or deuterium.

[0197] 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, an alkyl having 1 to 4 carbon atoms (such as methyl or t-butyl), phenyl, or naphthyl.

[0198] [Chemical formula] (mCP)

[0199] [Chemical formula]

[0200] [Chemical formula]

[0201] [Chemical formula]

[0202] <Anthracene-based compound> Examples of anthracene-based compounds as host materials include compounds represented by formula (3-H) and compounds represented by formula (3-H2). [Chemical formula]

[0203] In formula (3-H), X and Ar 4 are each independently hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted diarylamino, optionally substituted diheteroarylamino, optionally substituted arylheteroarylamino, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted arylthio or optionally substituted silyl, and all X and Ar 4 will not simultaneously be hydrogen, At least one hydrogen in the compound represented by formula (3-H) may be substituted with a halogen, cyano, deuterium, or a heteroaryl which may be substituted. The two aryls of the diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the diheteroarylamino are not bonded to each other or are bonded via a linking group, and the aryl and heteroaryl of the arylheteroarylamino are not bonded to each other or are bonded via a linking group.

[0204] Further, a multimer (preferably a dimer) may be formed with the structure represented by formula (3-H) as a unit structure. In this case, for example, there is a form in which the unit structures represented by formula (3-H) are bonded via X. Examples of X include a single bond, an arylene (such as phenylene, biphenylene, and naphthylene), and a heteroarylene (a group having a divalent valence such as a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring, and a phenyl-substituted carbazole ring).

[0205] Details of each group in the compound represented by formula (3-H) can be cited from the description in the above formula (1), and will be further described in the column of the following preferred embodiments.

[0206] Preferred embodiments of the above anthracene-based compound will be described below. The definitions of the symbols in the following structures are the same as those described above.

Chemical formula

[0207] In formula (3-H), X is each independently a group represented by formula (3-X1), formula (3-X2), or formula (3-X3), and the group represented by formula (3-X1), formula (3-X2), or formula (3-X3) is bonded to the anthracene ring of formula (3-H) at *. Preferably, two Xs do not simultaneously become a group represented by formula (3-X3). More preferably, two Xs do not simultaneously become a group represented by formula (3-X2).

[0208] Also, a multimer (preferably a dimer) may be formed with the structure represented by the formula (3-H) as a unit structure. In this case, for example, there is a form in which the unit structures represented by the formula (3-H) are bonded to each other via X, and examples of this X include a single bond, arylene (such as phenylene, biphenylene, and naphthylene), and heteroarylene (a group having a divalent valence such as a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring, and a phenyl-substituted carbazole ring).

[0209] The naphthylene moieties in the formula (3-X1) and the formula (3-X2) may be condensed with one benzene ring. The structure condensed in this way is as follows.

Chemical formula

[0210] Ar 1 and Ar 2 are each independently hydrogen, phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenylyl, or a group represented by the formula (A) (including carbazolyl, benzocarbazolyl, and phenyl-substituted carbazolyl). Note that when Ar 1 or Ar 2 is a group represented by the formula (A), the group represented by the formula (A) is bonded to the naphthalene ring in the formula (3-X1) or the formula (3-X2) at its *.

[0211] Ar 3 is phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenylyl, or a group represented by the formula (A) (including carbazolyl, benzocarbazolyl, and phenyl-substituted carbazolyl). Note that Ar 3When the group is represented by the formula (A), the group represented by the formula (A) is bonded to the single bond represented by the straight line in the formula (3-X3) at the *. That is, the anthracene ring of the formula (3-H) is directly bonded to the group represented by the formula (A).

[0212] Also, Ar 3 may have a substituent, and Ar 3 at least one hydrogen in may be further substituted with an alkyl having 1 to 4 carbon atoms, a cycloalkyl having 5 to 10 carbon atoms, phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by the formula (A) (including carbazolyl and phenyl-substituted carbazolyl). Note that when the substituent that Ar 3 has is a group represented by the formula (A), the group represented by the formula (A) is bonded to Ar in the formula (3-X3) at the * thereof 3 and is bonded to it.

[0213] Ar 4 is, independently of each other, hydrogen, phenyl, biphenylyl, terphenyl, naphthyl, or a silyl substituted with an alkyl having 1 to 4 carbon atoms (such as methyl, ethyl, t-butyl, etc.) and / or a cycloalkyl having 5 to 10 carbon atoms.

[0214] Examples of the alkyl having 1 to 4 carbon atoms that substitutes for silyl include methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl, cyclobutyl, etc., and the three hydrogens in silyl are each independently substituted with these alkyls.

[0215] Specific "silyl substituted with an alkyl having 1 to 4 carbon atoms" includes trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, tri-sec-butylsilyl, tri-t-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, t-butyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, t-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, t-butyldiisopropylsilyl, and the like.

[0216] The cycloalkyl having 5 to 10 carbon atoms that substitutes for silyl includes cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, norbornenyl, bicyclo[1.1.1]pentyl, bicyclo[2.0.1]pentyl, bicyclo[1.2.1]hexyl, bicyclo[3.0.1]hexyl, bicyclo[2.1.2]heptyl, bicyclo[2.2.2]octyl, adamantyl, decahydronaphthalenyl, decahydroazulenyl, and the like. The three hydrogens in silyl are each independently substituted with these cycloalkyls.

[0217] Specific "silyl substituted with a cycloalkyl having 5 to 10 carbon atoms" includes tricyclopentylsilyl, tricyclohexylsilyl, and the like.

[0218] The substituted silyl also includes dialkylcycloalkylsilyl substituted with two alkyls and one cycloalkyl, and alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyls. Specific examples of the alkyl and cycloalkyl for substitution are the groups described above.

[0219] Further, the hydrogen in the chemical structure of the anthracene-based compound represented by the formula (3-H) may be substituted with a group represented by the formula (A). When substituted with the group represented by the formula (A), the group represented by the formula (A) substitutes at least one hydrogen in the compound represented by the formula (3-H) therein.

[0220] The group represented by the formula (A) is one of the substituents that the anthracene-based compound represented by the formula (3-H) may have.

Chemical formula

[0221] In the formula (A), Y is -O-, -S- or >N-R 29 wherein R 21 ~R 28 are each independently hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted arylthio, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, optionally substituted amino, halogen, hydroxy or cyano, and among R 21 ~R 28 the adjacent groups do not combine with each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring, or form such a ring, and R 29 is hydrogen or optionally substituted aryl. Y in the formula (A) is preferably -O-.

[0222] R 21 ~R 28As the "alkyl" in the "optionally substituted alkyl", it may be either linear or branched, for example, linear alkyl having 1 to 24 carbon atoms or branched alkyl having 3 to 24 carbon atoms. Alkyl having 1 to 18 carbon atoms (branched alkyl having 3 to 18 carbon atoms) is preferred, alkyl having 1 to 12 carbon atoms (branched alkyl having 3 to 12 carbon atoms) is more preferred, alkyl having 1 to 6 carbon atoms (branched alkyl having 3 to 6 carbon atoms) is even more preferred, and alkyl having 1 to 4 carbon atoms (branched alkyl having 3 to 4 carbon atoms) is particularly preferred.

[0223] Specific examples of the "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, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl, etc.

[0224] R 21 ~R 28 As the "cycloalkyl" in the "optionally substituted cycloalkyl", 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, 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, etc. can be mentioned.

[0225] Specific "cycloalkyls" include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and their C1-C4 alkyl (especially methyl) substituents, norbornenyl, bicyclo[1.0.1]butyl, bicyclo[1.1.1]pentyl, bicyclo[2.0.1]pentyl, bicyclo[1.2.1]hexyl, bicyclo[3.0.1]hexyl, bicyclo[2.1.2]heptyl, bicyclo[2.2.2]octyl, adamantyl, diamantyl, decahydronaphthalenyl, decahydroazulenyl, and the like.

[0226] R 21 ~R 28 Examples of the "aryl" in the "optionally substituted aryl" in R~R include aryls having 6 to 30 carbon atoms, preferably aryls having 6 to 16 carbon atoms, more preferably aryls having 6 to 12 carbon atoms, and particularly preferably aryls having 6 to 10 carbon atoms.

[0227] Specific "aryls" include phenyl which is a monocyclic system, biphenylyl which is a bicyclic system, naphthyl which is a condensed bicyclic system, terphenylyl (m-terphenylyl, o-terphenylyl, p-terphenylyl) which is a tricyclic system, acenaphthylenyl, fluorenyl, phenalenyl, phenanthrenyl which are condensed tricyclic systems, triphenylenyl, pyrenyl, naphthacenyl which are condensed tetracyclic systems, perylenyl, pentacenyl which are condensed pentacyclic systems, and the like.

[0228] R 21 ~R 28 Examples of the "heteroaryl" in the "optionally substituted heteroaryl" in R~R include heteroaryls having 2 to 30 carbon atoms, preferably heteroaryls having 2 to 25 carbon atoms, more preferably heteroaryls having 2 to 20 carbon atoms, still more preferably heteroaryls having 2 to 15 carbon atoms, and particularly preferably heteroaryls having 2 to 10 carbon atoms. Further, examples of the heteroaryl include heterocycles containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen in addition to carbon as ring-constituting atoms.

[0229] Specific "heteroaryl" includes, for example, 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, quinazolinyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiinyl, phenoxazinyl, phenothiazinyl, phenazinyl, indolizinyl, furyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, thienyl, benzo[b]thienyl, dibenzothienyl, furazanyl, thianthrenyl, naphthobenzofuranyl, naphthobenzothienyl, etc.

[0230] R 21 ~R 28 The "alkoxy" in the "optionally substituted alkoxy" in R~R includes, for example, linear 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-chain alkoxy having 3 to 18 carbon atoms) is preferred, alkoxy having 1 to 12 carbon atoms (branched-chain alkoxy having 3 to 12 carbon atoms) is more preferred, alkoxy having 1 to 6 carbon atoms (branched-chain alkoxy having 3 to 6 carbon atoms) is still more preferred, and alkoxy having 1 to 4 carbon atoms (branched-chain alkoxy having 3 to 4 carbon atoms) is particularly preferred.

[0231] Specific "alkoxy" includes methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, etc.

[0232] R 21 ~R 28The "aryloxy" in the "optionally substituted aryloxy" is a group in which the hydrogen of the -OH group is substituted with an aryl, and this aryl is the group described as R 21 ~R 28 described for the "aryl" in. can be cited.

[0233] R 21 ~R 28 The "arylthio" in the "optionally substituted arylthio" is a group in which the hydrogen of the -SH group is substituted with an aryl, and this aryl is the group described as R 21 ~R 28 described for the "aryl" in. can be cited.

[0234] R 21 ~R 28 The "trialkylsilyl" in is a group in which the three hydrogens in the silyl group are each independently substituted with an alkyl, and this alkyl is the group described as R 21 ~R 28 described for the "alkyl" in. can be cited. Preferred alkyls for substitution are alkyls having 1 to 4 carbon atoms, specifically methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl, cyclobutyl, etc.

[0235] Specific examples of the "trialkylsilyl" group include trimethylsilyl, triethylsilyl, tripropylsilyl, tri-i-propylsilyl, tributylsilyl, tri-sec-butylsilyl, tri-t-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, i-propyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, t-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, i-propyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, t-butyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, t-butyldipropylsilyl, methyldi-i-propylsilyl, ethyldi-i-propylsilyl, butyldi-i-propylsilyl, sec-butyldi-i-propylsilyl, t-butyldi-i-propylsilyl, and the like.

[0236] R 21 ~R 28 Examples of the "tricycloalkylsilyl" group in 21 ~ 28 include groups in which the three hydrogens in the silyl group are each independently substituted with a cycloalkyl group, and this cycloalkyl group can be cited as the group described as the "cycloalkyl" group in 21 ~ 28 . Preferred cycloalkyl groups for substitution are cycloalkyl groups having 5 to 10 carbon atoms, specifically, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, bicyclo[1.1.1]pentyl, bicyclo[2.0.1]pentyl, bicyclo[1.2.1]hexyl, bicyclo[3.0.1]hexyl, bicyclo[2.1.2]heptyl, bicyclo[2.2.2]octyl, adamantyl, decahydronaphthalenyl, decahydroazulenyl, and the like. 21 ~R 28 Examples of specific "tricycloalkylsilyl" groups include tricyclopentylsilyl, tricyclohexylsilyl, and the like.

[0237]

[0238] ​Specific examples of dialkylcycloalkylsilyl substituted with two alkyls and one cycloalkyl and alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyls include silyls substituted with groups selected from the specific alkyls and cycloalkyls described above.

[0239] R 21 ~R 28 Examples of the "substituted amino" of the "optionally substituted amino" in R 21 ~R 28 include, for example, amino in which two hydrogens are substituted with aryl or heteroaryl. Amino in which two hydrogens are substituted with aryl is diaryl-substituted amino, amino in which two hydrogens are substituted with heteroaryl is diheteroaryl-substituted amino, and amino in which two hydrogens are substituted with aryl and heteroaryl is arylheteroaryl-substituted amino. This aryl or heteroaryl can cite the groups described as "aryl" or "heteroaryl" in R

[0240] Specific examples of the "substituted amino" include diphenylamino, dinaphthylamino, phenylnaphthylamino, dipyridylamino, phenylpyridylamino, naphthylpyridylamino, and the like.

[0241] R 21 ~R 28 Examples of the "halogen" in R

[0242] R 21 ~R 28Among the groups described as such, some may be substituted as described above, and examples of the substituents in this case include alkyl, cycloalkyl, aryl, or heteroaryl. This alkyl, cycloalkyl, aryl, or heteroaryl is the group described as "alkyl", "cycloalkyl", "aryl", or "heteroaryl" in R 21 ~R 28 above, and can be cited.

[0243] R in ">N-R 29 " as Y is hydrogen or aryl which may be substituted. Examples of this aryl are the groups described as "aryl" in R 29 ~R 21 ~R 28 above, and the substituents thereof can be cited as the groups described as substituents for R 21 ~R 28 above.

[0244] R 21 ~R 28Of these, adjacent groups may be bonded to each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring. The case where no ring is formed is a group represented by the following formula (A-1), and examples of the case where a ring is formed include groups represented by the following formulas (A-2) to (A-14). In the group represented by any of the formulas (A-1) to (A-14), at least one hydrogen may be substituted with alkyl, cycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, arylthio, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, diaryl-substituted amino, diheteroaryl-substituted amino, arylheteroaryl-substituted amino, halogen, hydroxy or cyano. In the diaryl-substituted amino, the two aryls are not bonded to each other or are bonded via a linking group. In the diheteroaryl-substituted amino, the two heteroaryls are not bonded to each other or are bonded via a linking group. In the arylheteroaryl-substituted amino, the aryl and the heteroaryl are not bonded to each other or are bonded via a linking group.

[0245]

Chemical formula

[0246] Examples of the ring formed by the bonding of adjacent groups to each other include a cyclohexane ring in the case of a hydrocarbon ring, and the ring structures described for "aryl" and "heteroaryl" in R 21 ~R 28 above for aryl rings and heteroaryl rings. These rings are formed so as to be condensed with one or two benzene rings in formula (A-1).

[0247] The group represented by formula (A) is a group obtained by removing one hydrogen at any position of formula (A), and * indicates that position. That is, the group represented by formula (A) may have any position as the bonding position. For example, any carbon atom on the two benzene rings in the structure of formula (A), R in the structure of formula (A) 21 ~R28 Among them, any atom on a ring formed by adjacent groups bonding to each other, or ">N-R as Y in the structure of formula (A) 29 ", R in 29 at any position in, or a group that can directly bond to N(R 29 serving as a bond) in ">N-R 29 can be. The same applies to the groups represented by any of formula (A-1) to formula (A-14).

[0248] Examples of the group represented by formula (A) include groups represented by any of formula (A-1) to formula (A-14), groups represented by any of formula (A-1) to formula (A-5) and formula (A-12) to formula (A-14) are preferred, groups represented by any of formula (A-1) to formula (A-4) are more preferred, groups represented by any of formula (A-1), formula (A-3) and formula (A-4) are even more preferred, and the group represented by formula (A-1) is particularly preferred.

[0249] Examples of the group represented by formula (A) include the following groups. Y and * in the formula have the same definitions as above.

Chemical formula

[0250]

Chemical formula

[0251] In the compound represented by formula (3-H), the group represented by formula (A) preferably has a form bonded to the naphthalene ring in formula (3-X1) or formula (3-X2), the single bond in formula (3-X3) and / or Ar in formula (3-X3). 3 and is preferably in a bonded form.

[0252] Also, all or part of the hydrogen in the chemical structure of the anthracene-based compound represented by formula (3-H) may be deuterium.

[0253] The anthracene-based compound as the host may be, for example, a compound represented by the following formula (3-H2). [Chemical formula]

[0254] In formula (3-H2), Ar c is an optionally substituted aryl or an optionally substituted heteroaryl, and 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, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted diarylamino, an optionally substituted diheteroarylamino, an optionally substituted arylheteroarylamino, an optionally substituted alkyl, an optionally substituted cycloalkyl, an optionally substituted alkenyl, an optionally substituted alkoxy, an optionally substituted aryloxy, an optionally substituted arylthio, or an optionally substituted silyl, and at least one hydrogen in the compound represented by formula (1) may be substituted with halogen, cyano, or deuterium. Note that the two aryls of the optionally substituted diarylamino are not bonded to each other or are bonded via a linking group, the two heteroaryls of the optionally substituted diheteroarylamino are not bonded to each other or are bonded via a linking group, and the aryl and heteroaryl of the optionally substituted arylheteroarylamino are not bonded to each other or are bonded via a linking group.

[0255] In formula (3-H2), the definitions of "optionally substituted aryl", "optionally substituted heteroaryl", "optionally substituted diarylamino", "optionally substituted diheteroarylamino", "optionally substituted arylheteroarylamino", "optionally substituted alkyl", "optionally substituted cycloalkyl", "optionally substituted alkenyl", "optionally substituted alkoxy", "optionally substituted aryloxy", "optionally substituted arylthio", or "optionally substituted silyl" are the same as those defined in the above formula (3-H), and the explanations in formula (1) can be cited. Note that the two aryls of the "optionally substituted diarylamino" are not bonded to each other or are bonded via a linking group, the two heteroaryls of the "optionally substituted diheteroarylamino" are not bonded to each other or are bonded via a linking group, and the aryl and heteroaryl of the "optionally substituted arylheteroarylamino" are not bonded to each other or are bonded via a linking group.

[0256] The "optionally substituted aryl" is preferably a group represented by any of the following formulas (3-H2-X1) to (3-H2-X7).

[0257] [Chemical formula]

[0258] In formulas (3-H2-X1) to (3-H2-X7), * indicates the bonding position. In formulas (3-H2-X1) to (3-H2-X3), Ar 21 , Ar 22 , and Ar 23Each independently is hydrogen, phenyl, biphenylyl, terphenylyl, quarterphenylyl, naphthyl, 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-based compound represented by formula (3-H).

[0259] In formula (3-H2-X4) to formula (3-H2-X7), Ar 24 、Ar 25 、Ar 26 、Ar 27 and Ar 28 Each independently is hydrogen, phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A). Further, one or more hydrogens in each of the groups represented by formula (3-H2-X1) to formula (3-H2-X7) may be substituted with an alkyl having 1 to 6 carbon atoms (preferably methyl or t-butyl).

[0260] Furthermore, preferred examples of the "optionally substituted aryl" include terphenylyl (particularly, m-terphenyl-5'-yl) which may be substituted with one or more substituents selected from the group consisting of phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, chrysenyl, triphenylenyl, pyrenyl, and the group represented by formula (A).

[0261] Examples of the "optionally substituted heteroaryl" also include the group represented by formula (A). In addition, specific examples of the "optionally substituted aryl" and the "optionally substituted heteroaryl" include dibenzofuryl, naphthobenzofuryl, phenyl-substituted dibenzofuryl, and the like.

[0262] At least one hydrogen in the compound represented by formula (1) may be substituted with a halogen, cyano, or deuterium. Examples of the "halogen" in this case include fluorine, chlorine, bromine, and iodine. In particular, a compound in which all hydrogens in the compound represented by formula (3-H2) are substituted with deuterium is preferred.

[0263] 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), Ar 11 ~Ar 18 At least two of them are preferably aryl which may be substituted or heteroaryl which may be substituted. That is, the anthracene-based compound represented by formula (3-H2) preferably has a structure in which at least three substituents selected from the group consisting of aryl which may be substituted and heteroaryl which may be substituted are bonded to the anthracene ring.

[0264] In the anthracene-based compound represented by formula (3-H2), Ar 11 ~Ar 18 Two of them are preferably aryl which may be substituted or heteroaryl which may be substituted, and the other six are preferably hydrogen, alkyl which may be substituted, cycloalkyl which may be substituted, alkenyl which may be substituted, or alkoxy which may be substituted. That is, the anthracene-based compound represented by formula (3-H2) more preferably has a structure in which three substituents selected from the group consisting of aryl which may be substituted and heteroaryl which may be substituted are bonded to the anthracene ring.

[0265] In the anthracene-based compound represented by formula (3-H2), Ar 11 ~Ar 18 More preferably, any two of them are aryl which may be substituted or heteroaryl which may be substituted, and the other six are hydrogen, methyl, or t-butyl.

[0266] Furthermore, in formula (3-H2), R c is hydrogen, and it is preferable that any six of Ar 11 ~Ar 18 are hydrogen.

[0267] The anthracene-based compound represented by formula (3-H2) is preferably an anthracene-based compound represented by the following formula (3-H2-A), (3-H2-B), (3-H2-C), (3-H2-D), or (3-H2-E).

Chemical formula

[0268] 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, quarterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A), and at least one hydrogen in these groups may be substituted with phenyl, biphenylyl, terphenylyl, quarterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A). Here, when all the hydrogens of the methylene in fluorenyl and benzofluorenyl are substituted with phenyl, these phenyls may be bonded to each other by a single bond. Ar c ’, Ar 11 ’, Ar 12 ’, Ar 13 ’, Ar 14 ’, Ar 15 ’, Ar 17 ’, and Ar18 A methyl or t-butyl group may be bonded to the carbon atom of the anthracene ring to which ’ is not bonded, instead of hydrogen.

[0269] Ar c ’, Ar 11 ’, Ar 12 ’, Ar 13 ’, Ar 14 ’, Ar 15 ’, Ar 17 ’, and Ar 18 ’ and Ar are each preferably a group represented by any of the above formulas (3-H2-X1) to (3-H2-X7) when they are each a substituted or unsubstituted phenyl or a substituted or unsubstituted naphthyl.

[0270] Ar c ’, Ar 11 ’, Ar 12 ’, Ar 13 ’, Ar 14 ’, Ar 15 ’, Ar 17 ’, and Ar 18 ’ and Ar are each more preferably independently phenyl, biphenylyl (particularly, biphenyl-2-yl or biphenyl-4-yl), terphenylyl (particularly, m-terphenyl-5’-yl), naphthyl, phenanthryl, fluorenyl, or a group represented by any of the above formulas (A-1) to (A-4). At this time, at least one hydrogen in these groups may be substituted with phenyl, biphenylyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any of the above formulas (A-1) to (A-4).

[0271] Further, at least one hydrogen in the compound represented by the formula (3-H2-A), (3-H2-B), (3-H2-C), (3-H2-D), or (3-H2-E) may be substituted with halogen, cyano, or deuterium. The deuterated form is preferred, and the form in which all anthracene rings are deuterated or the form in which all hydrogen atoms are deuterated is preferred.

[0272] As the anthracene compound represented by the particularly preferred formula (3-H2), the anthracene compound represented by the following formula (3-H2-Aa) can be mentioned. [Chemical formula]

[0273] In formula (3-H2-Aa), Ar c ’, Ar 14 ’, and Ar 15 ’ are each independently 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 may be substituted with phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by any of formulas (A-1) to (A-11). Here, when all the hydrogens of the methylene in fluorenyl and benzofluorenyl are substituted with phenyl, these phenyls may be bonded to each other by a single bond. Also, Ar c ’, Ar 14 ’, and Ar 15 ’ may be substituted with methyl or t-butyl instead of hydrogen at the carbon atom on the anthracene ring where they are not bonded. At least one hydrogen in the compound represented by formula (3-H2-Aa) is not substituted with halogen or cyano, or is substituted, and at least one hydrogen in the compound represented by formula (3-H2-Aa) is substituted with deuterium.

[0274] In formula (3-H2-Aa), Ar c ’, Ar 14 ’, and Ar 15' is preferably each independently phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any of the above formulas (A-1) to (A-4), and at least one hydrogen in these groups may be substituted with phenyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any of the formulas (A-1) to (A-4).

[0275] In the compound represented by the formula (3-H2-Aa), at least the hydrogen bonded to the carbon at the 10th position of the anthracene ring (the carbon to which Ar c ' is bonded is the 9th position) is preferably substituted with deuterium. That is, the compound represented by the formula (3-H2-Aa) is preferably a compound represented by the following formula (3-H2-Ab). In the formula (3-H2-Ab), D is deuterium, and Ar c ', Ar 14 ', and Ar 15 ' are the same as the definitions in the formula (1Aa). D in the formula (1Ab) indicates that at least this position is deuterium, and any one or more of the other hydrogens in the formula (3-H2-Aa) may be deuterium at the same time, and it is also preferable that all the hydrogens in the formula (3-H2-Aa) are deuterium.

[0276]

Chemical formula

[0277] Specific examples of the anthracene-based compound include, for example, compounds represented by the following various formulas. In the following structural formulas, "Me" represents methyl, "D" represents deuterium, and "tBu" represents t-butyl.

[0278]

Chemical formula

[0279]

Chemical formula

[0280]

Chem.

[0281]

Chem.

[0282]

Chem.

[0283]

Chem.

[0284]

Chem.

[0285]

Chem.

[0286] In addition, as other specific examples of anthracene-based compounds, for example, compounds represented by the following formulas (3-131-Y) to (3-179-Y), compounds represented by the following formulas (3-180-Y) to (3-182-Y), the following formula (3-183-N), the following formulas (3-184-Y) to (3-254-Y), formulas (3-2554-Y) to (3-269-Y), and compounds represented by the following formulas (3-500) to (3-557) and formulas (3-600) to (3-620) can be mentioned. In the compounds represented by the following formulas (3-131-Y) to (3-179-Y), compounds represented by the following formulas (3-180-Y) to (3-182-Y), the following formula (3-183-N), the following formulas (3-184-Y) to (3-254-Y), formulas (3-2554-Y) to (3-269-Y), and the following formulas (3-500) to (3-557) and formulas (3-600) to (3-620), the hydrogen atoms may be partially or entirely substituted with deuterium. In the formulas, Y is -O-, -S-, >N-R 29 (R 29 has the same definition as above), or >C(-R 30 )2 (R 30 may be either aryl or alkyl which may be linked), and R 29 is, for example, phenyl, and R 30 is, for example, methyl. When the formula number, for example, when Y is O, formula (3-131-Y) is formula (3-131-O), and when Y is -S- or >N-R 29 , they are formula (3-131-S) and formula (3-131-N), respectively.

[0287]

Chemical formula

[0288]

Chemical formula

[0289]

Chemical formula

[0290] [Chemistry]

[0291] [Chemistry] TIFF0007693169000098.tif139132

[0292] [Chemistry]

[0293] [Chemistry]

[0294] [Chemistry]

[0295] [Chemistry]

[0296] [Chemistry]

[0297] [Chemistry]

[0298] [Chemistry]

[0299] [Chemistry]

[0300] [Chemistry]

[0301] [Chemical formula]

[0302] [Chemical formula]

[0303] [Chemical formula]

[0304] [Chemical formula]

[0305] [Chemical formula]

[0306] Among these compounds, compounds represented by 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 (3-501), 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 (3-620) are preferred. Also, Y is preferably -O-.

[0307] The above anthracene-based compound is a compound having a reactive group at a desired position of the anthracene skeleton and an anthracene-based compound represented by the formula (3-H), and X and Ar 4 and a compound having a reactive group in a partial structure such as the structure of the formula (A) as a starting material, and can be produced by applying Suzuki coupling, Negishi coupling, or other known coupling reactions. Examples of the reactive groups of these reactive compounds include halogen and boronic acid. As a specific production method, for example, the synthesis methods in paragraphs

[0089] to

[0175] of International Publication No. 2014 / 141725 can be referred to.

[0308] <Fluorene-based compound> The compound represented by the formula (4-H) basically functions as a host. [Chemical formula]

[0309] In the formula (4-H), R 1 to R 10 are each independently hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the fluorene skeleton in the formula (4-H) via a linking group), diarylamino (the two aryls are not bonded to each other or may be bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or may be bonded via a single bond or a linking group), arylheteroarylamino (the aryl and the heteroaryl are not bonded to each other or may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, and at least one hydrogen in these is unsubstituted or substituted with aryl, heteroaryl, alkyl or cycloalkyl. Also, 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 do not each independently combine to form a condensed ring or a spiro ring, or do form one, and at least one hydrogen in the formed ring is not substituted or is substituted with aryl, heteroaryl (the heteroaryl may be bonded to the formed ring via a linking group), diarylamino (the two aryls are not bonded to each other or may be bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or may be bonded via a single bond or a linking group), arylheteroarylamino (the aryl and the heteroaryl are not bonded to each other or may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, and at least one hydrogen in these is not substituted or is substituted with aryl, heteroaryl, alkyl or cycloalkyl, and at least one hydrogen in the compound represented by formula (4-H) may be substituted with halogen, cyano or deuterium.

[0310] Details of each group in the definition of formula (4-H) can cite the description in the polycyclic aromatic compound of formula (1) described above.

[0311] R 1 to R 10 Examples of the alkenyl from R

[0312] In addition, as specific examples of heteroaryl, a monovalent group represented by removing any one hydrogen atom from a compound of the following formula (4-Ar1), formula (4-Ar2), formula (4-Ar3), formula (4-Ar4), or formula (4-Ar5) can also be mentioned.

[0313]

Chemical formula

[0314] In formulas (4-Ar1) to (4-Ar5), Y 1 is each independently O, S, or N-R, R is phenyl, biphenylyl, naphthyl, anthracenyl, or hydrogen, and 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.

[0315] These heteroaryls may be bonded to the fluorene skeleton in formula (4-H) via a linking group. That is, not only can the fluorene skeleton in formula (4-H) and the above heteroaryl be directly bonded, but they may also be bonded via a linking group therebetween. Examples of this linking group include phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH2CH2-, -CH2CH2O-, or -OCH2CH2O-.

[0316] Also, R in formula (4-H) 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 may each independently bond to form a condensed ring, and R 9 and R 10 may bond to form a spiro ring. R 1 from R8 The condensed ring formed by [description of formation] is a ring that condenses with 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 the benzene ring in formula (4-H) are a naphthalene ring, a phenanthrene ring, etc. R 9 and R 10 The spiro ring formed by [description of formation] is a ring that is 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, and examples include a fluorene ring, etc.

[0317] The compound represented by formula (4-H) is preferably a compound represented by the following formula (4-H-1), formula (4-H-2) or formula (4-H-3), and respectively, in formula (4-H), a compound in which the benzene ring formed by the bonding of R 1 and R 2 is condensed, a compound in which the benzene ring formed by the bonding of R 3 and R 4 is condensed, and a compound in which none of R 1 to R 8 are bonded.

[0318]

Chemical formula

[0319] 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), and the definitions of R 11 to R 14 in formula (4-H-1) and formula (4-H-2) are also the same as the corresponding R 1 to R 10 in formula (4-H).

[0320] The compound represented by 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), and in formula (4-H-1), formula (4-H-1) or formula (4-H-3), respectively, R 9 and R 10 are bonded to form a spiro-fluorene ring.

[0321]

Chemical formula

[0322] The definitions of R 2 to R 7 in formula (4-1A), formula (4-2A) and formula (4-3A) are the same as the corresponding R 2 to R 7 in formula (4-1), formula (4-2) and formula (4-3), and the definitions of R 11 to R 14 in formula (4-1A) and formula (4-2A) are also the same as the R 11 to R 14 in formula (4-1) and formula (4-2).

[0323] In addition, all or part of the hydrogen in the compound represented by formula (4-H) may be substituted with halogen, cyano or deuterium.

[0324] More specific examples of the fluorene-based compound as the host of the present invention include compounds represented by the following structural formulas. Note that "Me" represents methyl.

Chemical formula

[0325] <Dibenzocrisene-based compound> The dibenzocrisene-based compound as the host is, for example, a compound represented by the following formula (5-H).

Chemical formula

[0326] In formula (5-H), R 1 to R 16 are each independently hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the dibenzocrisene skeleton in formula (5-H) via a linking group), diarylamino (the two aryls are not bonded to each other or may be bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or may be bonded via a single bond or a linking group), arylheteroarylamino (the aryl and heteroaryl are not bonded to each other or may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, at least one hydrogen in these is unsubstituted or substituted by aryl, heteroaryl, alkyl or cycloalkyl, and also, R 1 to R 16 among them, adjacent groups are not bonded to form a fused ring or are bonded to form a fused ring, and at least one hydrogen in the formed ring is unsubstituted or substituted by aryl, heteroaryl (the heteroaryl may be bonded to the formed ring via a linking group), diarylamino (the two aryls are not bonded to each other or may be bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or may be bonded via a single bond or a linking group), arylheteroarylamino (the aryl and heteroaryl are not bonded to each other or may be bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, at least one hydrogen in these is unsubstituted or substituted by aryl, heteroaryl, alkyl or cycloalkyl, and at least one hydrogen in the compound represented by formula (5-H) may be substituted by halogen, cyano or deuterium.

[0327] Regarding the details of each group in the definition of formula (5-H), the description of the polycyclic aromatic compound of formula (1) mentioned above can be cited.

[0328] Examples of the alkenyl in the definition of formula (5-H) include alkenyls having 2 to 30 carbon atoms, preferably alkenyls having 2 to 20 carbon atoms, more preferably alkenyls having 2 to 10 carbon atoms, still more preferably alkenyls having 2 to 6 carbon atoms, and particularly preferably alkenyls having 2 to 4 carbon atoms. 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.

[0329] In addition, as specific examples of heteroaryl, monovalent groups represented by removing any one hydrogen atom from the compounds of the following formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4), or formula (5-Ar5) can also be mentioned.

[0330]

Chemical formula

[0331] In formula (5-Ar1) to formula (5-Ar5), Y 1 is each independently O, S, or N-R, R is phenyl, biphenylyl, naphthyl, anthracenyl, or hydrogen, and at least one hydrogen in the structures of formula (5-Ar1) to formula (5-Ar5) may be substituted with phenyl, biphenylyl, naphthyl, anthracenyl, phenanthrenyl, methyl, ethyl, propyl, or butyl.

[0332] These heteroaryls may be bonded to the dibenzocrisene skeleton in formula (5-H) via a linking group. That is, not only can the dibenzocrisene skeleton in formula (5-H) and the above heteroaryl be directly bonded, but they may also be bonded via a linking group therebetween. Examples of this linking group include phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH2CH2-, -CH2CH2O-, or -OCH2CH2O-.

[0333] The compound represented by formula (5-H) preferably has R 1 , R 4 , R 5 , R 8 , R 9 , R 12 , R 13 and R 16 being 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) (the monovalent group having the structure may be bonded to the dibenzocrisene skeleton in formula (5-H) via phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH2CH2-, -CH2CH2O-, or -OCH2CH2O-), methyl, ethyl, propyl, or butyl, preferably.

[0334] 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 , R13 and R 15 and R 16 is hydrogen. In this case, R 3 and R 6 and R 11 and R 14 at least one (preferably one or two, more preferably one) of is a monovalent group having a structure of formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5) via a single bond, phenylene, biphenylene, naphthylene, anthracenylene, methylene, ethylene, -OCH2CH2-, -CH2CH2O-, or -OCH2CH2O-; other than the at least one (i.e., other than the position substituted with the monovalent group having the structure) is hydrogen, phenyl, biphenylyl, naphthyl, anthracenyl, methyl, ethyl, propyl, or butyl, and at least one hydrogen in these may be substituted with phenyl, biphenylyl, naphthyl, anthracenyl, methyl, ethyl, propyl, or butyl.

[0335] Also, when a monovalent group having a structure represented by formula (5-Ar1) to formula (5-Ar5) is selected as R 2 and R 3 and R 6 and R 7 and R 10 and R 11 and R 14 and R 15 in formula (5-H), at least one hydrogen in the structure may be combined with any one of R 1 to R 16 in formula (5-H) to form a single bond.

[0336] More specific examples of the dibenzocrisene-based compound as the host of the present invention include compounds represented by the following structural formulas. Note that "tBu" represents t-butyl.

Chemical formula

[0337] [Chemical]

[0338] The above-described materials for the light-emitting layer (host materials and dopant materials) can also be used as light-emitting layer materials in the form of a polymer compound obtained by polymerizing a reactive compound having a reactive substituent substituted thereon as a monomer, or a polymer crosslinked body thereof, or a pendant polymer compound obtained by reacting a main-chain polymer with the reactive compound, or a pendant polymer crosslinked body thereof. As the reactive substituent in this case, the description of the polycyclic aromatic compound represented by the formula (1) can be cited.

[0339] <Light-emitting layer containing an assisting dopant and an emitting dopant> The light-emitting layer in the organic electroluminescent element may contain a host compound as the first component, an assisting dopant (compound) as the second component, and an emitting dopant (compound) as the third component. It is also preferable to use the polycyclic aromatic compound of the present invention as the emitting dopant. As the assisting dopant (compound), a thermally activated delayed phosphor can be used.

[0340] In the following description, an organic electroluminescent element using a thermally activated delayed phosphor as an assisting dopant may be referred to as a "TAF element" (TADF Assisting Fluorescence element). The "host compound" in the TAF element means a compound in which the excited singlet energy level determined from the shoulder on the short-wavelength side of the peak of the fluorescence spectrum is higher than that of the thermally activated delayed phosphor as the second component and the emitting dopant as the third component.

[0341] "Thermally activated delayed phosphor" means a compound that can absorb thermal energy to cause reverse intersystem crossing from an excited triplet state to an excited singlet state, and emit delayed fluorescence by radiative deactivation from the excited singlet state. However, "thermally activated delayed fluorescence" includes those that pass through a higher-order triplet state in the excitation process from an excited triplet state to an excited singlet state. For example, papers by Monkman et al. of Durham University (NATURE COMMUNICATIONS, 7:13680, DOI: 10.1038 / ncomms13680), papers by Hosokai et al. of the National Institute of Advanced Industrial Science and Technology (Hosokai et al., Sci. Adv. 2017;3: e1603282), papers by Sato et al. of Kyoto University (Scientific Reports, 7:4820, DOI:10.1038 / s41598-017-05007-7), and a conference presentation by Sato et al. of Kyoto University (98th Spring Meeting of the Chemical Society of Japan, Presentation No.: 2I4-15, Mechanism of highly efficient luminescence in organic electroluminescence using DABNA as a luminescent molecule, Graduate School of Engineering, Kyoto University) can be cited. In the present invention, for a sample containing a target compound, when the fluorescence lifetime is measured at 300K and a slow fluorescence component is observed, the target compound is determined to be a "thermally activated delayed phosphor". Here, the slow fluorescence component refers to a component with a fluorescence lifetime of 0.1 μsec or more. The measurement of the fluorescence lifetime can be performed, for example, using a fluorescence lifetime measurement device (manufactured by Hamamatsu Photonics, C11367-01).

[0342] 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 luminescence of the polycyclic aromatic compound of the present invention.

[0343] Fig. 2 shows the energy level diagram of the light-emitting layer of a TAF device using a general fluorescent dopant as the emitting dopant (ED). In the figure, the energy level of the ground state of the host is E(1,G), the excited singlet energy level obtained from the short-wavelength side shoulder of the fluorescence spectrum of the host is E(1,S,Sh), the excited triplet energy level obtained from the short-wavelength side shoulder of the phosphorescence spectrum of the host is E(1,T,Sh), the energy level of the ground state of the assisting dopant as the second component is E(2,G), the excited singlet energy level obtained from the short-wavelength side shoulder of the fluorescence spectrum of the assisting dopant as the second component is E(2,S,Sh), the excited triplet energy level obtained from the short-wavelength side shoulder of the phosphorescence spectrum of the assisting dopant as the second component is E(2,T,Sh), the energy level of the ground state of the emitting dopant as the third component is E(3,G), the excited singlet energy level obtained from the short-wavelength side shoulder of the fluorescence spectrum of the emitting dopant as the third component is E(3,S,Sh), and the excited triplet energy level obtained from the short-wavelength side shoulder of the phosphorescence spectrum of the emitting dopant as the third component is E(3,T,Sh). In the TAF device, when a general fluorescent dopant is used as the emitting dopant (ED), the energy up-converted by the assisting dopant transfers to the excited singlet energy level E(3,S,Sh) of the emitting dopant and emits light. However, a part of the excited triplet energy E(2,T,Sh) on the assisting dopant transfers to the excited triplet energy level E(3,T,Sh) of the emitting dopant, or an intersystem crossing occurs from the excited singlet energy level E(3,S,Sh) to the excited triplet energy level E(3,T,Sh) on the emitting dopant, and subsequently, it thermally deactivates to the ground state E(3,G). Through this path, a part of the energy is not used for light emission, resulting in energy waste.

[0344] In contrast, in the organic electroluminescent device of this embodiment, the energy transferred from the assisting dopant to the emitting dopant can be efficiently utilized for light emission, thereby realizing high luminous efficiency. This is presumably due to the following light emission mechanism.

[0345] The preferable energy relationship in the organic electroluminescent device of this embodiment is shown in FIG. 3. In the organic electroluminescent device of this embodiment, the compound having a boron atom as the emitting dopant has a high excited triplet energy level E(3,T,Sh). Therefore, even when the excited singlet energy upconverted by the assisting dopant undergoes intersystem crossing to the excited triplet energy level E(3,T,Sh) in the emitting dopant, it is either upconverted on the emitting dopant or recovered to the excited triplet energy level E(2,T,Sh) on the assisting dopant (thermally activated delayed phosphor). Therefore, the generated excited energy can be used for light emission without waste. Also, by separating the upconversion and light emission functions into two types of molecules each proficient in them, it is expected that the residence time of high energy will decrease and the burden on the compound will decrease.

[0346] In this embodiment, as the host compound, known ones can be used, for example, compounds having at least one of a carbazole ring and a furan ring can be mentioned. Among them, it is preferable to use a compound in which at least one of furanyl and carbazolyl is bonded to at least one of arylene and heteroarylene. Specific examples include mCP and mCBP.

[0347] The triplet excitation energy level E(1,T,Sh) determined from the shoulder on the shorter wavelength side of the peak of the phosphorescence spectrum of the host compound is preferably higher than the triplet excitation energy levels E(2,T,Sh) and E(3,T,Sh) of the emitting dopant or assisting dopant having the highest triplet excitation energy level in the light-emitting layer from the viewpoint of promoting rather than inhibiting the generation of TADF in the light-emitting layer. Specifically, the triplet excitation energy level E(1,T,Sh) of the host compound is preferably 0.01 eV or more, more preferably 0.03 eV or more, and even more preferably 0.1 eV or more higher than E(2,T,Sh) and E(3,T,Sh). Also, a compound having TADF activity may be used as the host compound.

[0348] As the host compound, for example, a compound represented by any of the above formulas (H1), (H2), and (H3) can be used.

[0349] <Thermally activated delayed phosphor (assisting dopant)> The thermally activated delayed phosphor (TADF compound) used in the TAF element is preferably a donor-acceptor type thermally activated delayed phosphor (D-A type TADF compound) designed to localize the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in the molecule using an electron-donating substituent called a donor and an electron-accepting substituent called an acceptor so that efficient reverse intersystem crossing occurs. Here, in this specification, the "electron-donating substituent" (donor) means a substituent and partial structure in which the HOMO orbital is localized in the thermally activated delayed phosphor molecule, and the "electron-accepting substituent" (acceptor) means a substituent and partial structure in which the LUMO orbital is localized in the thermally activated delayed phosphor molecule.

[0350] Generally, thermally activated delayed phosphors using donors or acceptors have a large spin-orbit coupling (SOC) due to their structure, and a small exchange interaction between the HOMO and LUMO, resulting in a small ΔE(ST). Therefore, a very fast reverse intersystem crossing rate can be obtained. On the other hand, thermally activated delayed phosphors using donors or acceptors have a large structural relaxation in the excited state (in some molecules, since the stable structures in the ground state and the excited state are different, when the conversion from the ground state to the excited state occurs due to an external stimulus, the structure then changes to the stable structure in the excited state), giving a broad emission spectrum, which may reduce the color purity when used as a luminescent material.

[0351] As a thermally activated delayed phosphor in the TAF element, for example, a compound in which a donor and an acceptor are bonded directly or via a spacer can be used. As the electron-donating group (donor structure) and the electron-accepting group (acceptor structure) used in the thermally activated delayed phosphor of the present invention, for example, the structures described in Chemistry of Materials, 2017, 29, 1946-1963 can be used. Examples of the donor structure include carbazole, dimethylcarbazole, di-tert-butylcarbazole, dimethoxycarbazole, tetramethylcarbazole, benzofluorocarbazole, benzothienocarbazole, phenyldihydroindolocarbazole, phenylbicarbozole, bicarbozole, tercarbazole, diphenylcarbazolylamine, tetraphenylcarbazolyl diamine, phenoxazine, dihydrophenazine, phenothiazine, dimethyldihydroacridine, diphenylamine, bis(tert-butyl)phenyl)amine, (diphenylamino)phenyl)diphenylbenzenediamine, dimethyltetraphenyldihydroacridinediamine, tetramethyl-dihydro-indenacridine, and diphenyl-dihydrodibenzazasiline. Examples of the acceptor structure include sulfonyldibenzene, benzophenone, phenylene bis(phenylmethanone), benzonitrile, isonicotinonitrile, phthalonitrile, isophthalonitrile, terephthalonitrile, benzenetricarbonitrile, triazole, oxazole, thiadiazole, benzothiazole, benzobis(thiazole), benzoxazole, benzobis(oxazole), quinoline, benzimidazole, dibenzoquinoxaline, heptaazaphenalene, thioxantone dioxide, dimethylanthraquinone, anthraquinone, cycloheptabipyridine, fluorenedicarbonitrile, triphenyltriazine, pyrazinedicarbonitrile, pyrimidine, phenylpyrimidine, methylpyrimidine, pyridinedicarbonitrile, dibenzoquinoxalinedicarbonitrile, bis(phenylsulfonyl)benzene, dimethylthioxanthene dioxide, thianthrene tetroxide, and tris(dimethylphenyl)borane.In particular, the compound having thermally activated delayed fluorescence in the TAF element is preferably a compound having at least one selected from carbazole, phenoxazine, acridine, triazine, pyrimidine, pyrazine, thioxanthene, benzonitrile, phthalonitrile, isophthalonitrile, diphenyl sulfone, triazole, oxadiazole, thiadiazole, and benzophenone as a partial structure.

[0352] The compound used as the second component of the light-emitting layer in the TAF element is preferably a thermally activated delayed phosphor, and its emission spectrum preferably overlaps at least partially with the absorption peak of the emitting dopant. Hereinafter, compounds that can be used as the second component (thermally activated delayed phosphor) of the light-emitting layer in the TAF element are exemplified. However, the compounds that can be used as thermally activated delayed phosphors in the TAF element should not be construed as being limited by the following exemplified compounds. In the following formulas, Me represents methyl, t-Bu represents t-butyl, and the wavy line represents the bonding position.

[0353]

Chemical formula

[0354]

Chemical formula

[0355]

Chemical formula

[0356]

Chemical formula

[0357]

Chemical formula

[0358] Furthermore, as the thermally activated delayed phosphor, a compound represented by any of the following formulas (AD1), (AD2), and (AD3) can also be used.

Chemical formula

[0359] In the above formulas (AD1), (AD2) and (AD3), M is independently a single bond, -O-, >N-Ar or >CAr2, and from the viewpoints of the depth of the HOMO of the formed partial structure and the heights of the singlet excitation energy level and the triplet excitation 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, and is independently an arylene having 6 to 18 carbon atoms. From the viewpoint of the magnitude of the conjugation oozing from the donor partial structure and the acceptor partial structure, an arylene having 6 to 12 carbon atoms is preferable. More specifically, phenylene, methylphenylene and dimethylphenylene can be mentioned. Q is independently =C(-H)- or =N-, and from the viewpoints of the shallowness of the LUMO of the formed partial structure and the heights of the singlet excitation energy level and the triplet excitation energy level, it is preferably =N-. Ar is independently hydrogen, aryl having 6 to 24 carbon atoms, heteroaryl having 2 to 24 carbon atoms, alkyl having 1 to 12 carbon atoms or cycloalkyl having 3 to 18 carbon atoms. From the viewpoints of the depth of the HOMO of the formed partial structure and the heights of the singlet excitation energy level and the triplet excitation energy level, it is preferably hydrogen, aryl having 6 to 12 carbon atoms, 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, triazolyl, carbazolyl, dimethylcarbazolyl, di-tert-butylcarbazolyl, benzimidazole or phenylbenzimidazole, and still more preferably hydrogen, phenyl or carbazolyl. m is 1 or 2. n is an integer of ~(6-m), and from the viewpoint of steric hindrance, it is preferably an integer of 4~(6-m). Further, at least one hydrogen in the compound represented by the above formulas may be substituted with a halogen or deuterium.

[0360] The compound used as the second component of this embodiment is, more specifically, 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 DCzmCzTrz.

[0361] The compound used as the second component of this embodiment may be a donor-acceptor type TADF compound represented by D-A in which one donor D and one acceptor A are directly bonded or bonded via a linking group, but it is preferably one having a structure represented by the following formula (DAD1) in which a plurality of donors D are directly bonded or bonded via a linking group to one acceptor A, because the characteristics of the organic electroluminescent element will be more excellent. (D 1 -L 1 )n-A 1 (DAD1) The formula (DAD1) includes a compound represented by the following formula (DAD2). D 2 -L 2 -A 2 -L 3 -D 3 (DAD2) In the formula (DAD1) and the formula (DAD2), D 1 , D 2 and D 3 each independently represent a donor group. As the donor group, the above donor structures can be adopted. A 1 and A 2 each independently represent an acceptor group. As the acceptor group, the above acceptor structures can be adopted. L 1 , L 2 and L 3Each independently represents 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, preferably an arylene having 6 to 18 carbon atoms, more preferably an arylene having 6 to 12 carbon atoms. L 1 , L 2 and L 3 are each more preferably independently phenylene, methylphenylene or dimethylphenylene. In formula (DAD1), n is 2 or more and represents an integer equal to or less than the maximum number of substituents that A 1 can have. n may be selected, for example, within the range of 2 to 10 or within the range of 2 to 6. When n is 2, it becomes a compound represented by formula (DAD2). The n D 1 s are the same or different, and the n L 1 s 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 to these compounds.

[0362]

Chemical formula

[0363] In this embodiment, the light-emitting layer may be either a single layer or a plurality of 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 of each may be contained in a plurality of layers. The host compound, the thermally activated delayed phosphor, and the polycyclic aromatic compound contained in the light-emitting layer may each be of one type or a plurality of combinations. The assisting dopant and the emitting dopant may be entirely or partially contained in the host compound as a matrix. The light-emitting layer doped with the assisting dopant and the emitting dopant can be formed by a method of forming a film of the host compound, the assisting dopant, and the emitting dopant by a ternary co-evaporation method, a method of mixing the host compound, the assisting dopant, and the emitting dopant in advance and then co-evaporating them simultaneously, a wet film-forming method such as applying a composition (paint) for forming a light-emitting layer prepared by dissolving the host compound, the assisting dopant, and the emitting dopant in an organic solvent, and the like.

[0364] The amount of the host compound used varies depending on the type of the host compound and may be determined according to the characteristics of the host compound. A guideline for the amount of the host compound used is preferably 40 to 99.999% by mass of the entire material for the light-emitting layer, more preferably 50 to 99.99% by mass, and still more preferably 60 to 99.9% by mass. If it is within the above range, it is preferable, for example, in terms of efficient charge transport and efficient energy transfer to the dopant.

[0365] The amount of the assisting dopant (thermally activated delayed phosphor) used varies depending on the type of the assisting dopant and may be determined according to the characteristics of the assisting dopant. A guideline for the amount of the assisting dopant used is preferably 1 to 60% by mass of the entire material for the light-emitting layer, more preferably 2 to 50% by mass, and still more preferably 5 to 30% by mass. If it is within the above range, it is preferable, for example, in terms of efficiently transferring energy to the emitting dopant.

[0366] The amount of the emitting dopant (compound having boron atoms) used varies depending on the type of the emitting dopant, and it may be determined according to the characteristics of the emitting dopant. The guideline for the amount of the emitting dopant used is preferably 0.001 to 30% by mass, more preferably 0.01 to 20% by mass, and still more preferably 0.1 to 10% by mass of the entire material for the light-emitting layer. If it is within the above range, for example, it is preferable in that the concentration quenching phenomenon can be prevented.

[0367] In terms of preventing the concentration quenching phenomenon, it is preferable that the amount of the emitting dopant used is low. In terms of the efficiency of the thermally activated delayed fluorescence mechanism, it is preferable that the amount of the assisting dopant used is high. Further, in terms 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.

[0368] 2-1-3. Substrate in the organic electroluminescent element The substrate 101 is a support for the organic EL element 100, and usually, quartz, glass, metal, plastic, etc. are used. The substrate 101 is formed in a plate shape, film shape, or sheet shape according to the purpose, and for example, a glass plate, metal plate, metal foil, plastic film, plastic sheet, etc. are used. Among them, a glass plate and a plate made of a transparent synthetic resin such as polyester, polymethacrylate, polycarbonate, or polysulfone are preferable. In the case of a glass substrate, soda-lime glass, alkali-free glass, etc. are used, and the thickness only needs to be sufficient to maintain mechanical strength, so for example, 0.2 mm or more is sufficient. As the upper limit value of the thickness, for example, it is 2 mm or less, preferably 1 mm or less. Regarding the glass material, since it is better that there are fewer eluted ions from the glass, alkali-free glass is preferable, but soda-lime glass with a barrier coat such as SiO2 is also commercially available, so this can be used. Further, in order to enhance the gas barrier property, a gas barrier film such as a dense silicon oxide film may be provided on at least one side of the substrate 101. In particular, when a plate, film, or sheet made of a synthetic resin with low gas barrier property is used as the substrate 101, it is preferable to provide a gas barrier film.

[0369] 2-1-4. Anode in Organic Electroluminescent Element The anode 102 serves to inject holes into the light-emitting layer 105. When a hole injection layer 103 and / or a hole transport layer 104 are provided between the anode 102 and the light-emitting layer 105, holes are injected into the light-emitting layer 105 through these layers.

[0370] Examples of materials for forming the anode 102 include inorganic compounds and organic compounds. Examples of inorganic compounds include metals (such as aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (such as indium oxide, tin oxide, indium-tin oxide (ITO), indium-zinc oxide (IZO), etc.), metal halides (such as copper iodide, etc.), copper sulfide, carbon black, ITO glass, Nesa glass, etc. Examples of organic compounds include polythiophenes such as poly(3-methylthiophene), and conductive polymers such as polypyrrole and polyaniline. In addition, it can be appropriately selected and used from among substances used as anodes of organic EL elements.

[0371] The resistance of the transparent electrode is not limited as long as sufficient current can be supplied for the light emission of the light-emitting element, but it is desirable to have a low resistance from the viewpoint of the power consumption of the light-emitting element. For example, an ITO substrate with a resistance of 300 Ω / sq or less can function as an element electrode, but since it is now possible to supply substrates with a resistance of about 10 Ω / sq, it is particularly desirable to use low-resistance products with a resistance of, for example, 100 to 5 Ω / sq, preferably 50 to 5 Ω / sq. The thickness of the ITO can be arbitrarily selected according to the resistance value, but it is usually used in the range of 50 to 300 nm.

[0372] 2-1-5. Hole Injection Layer and Hole Transport Layer in Organic Electroluminescent Element The hole injection layer 103 serves to efficiently inject holes moving from the anode 102 into the light-emitting layer 105 or the hole transport layer 104. The hole transport layer 104 serves to efficiently transport holes injected from the anode 102 or holes injected from the anode 102 through the hole injection layer 103 to the light-emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are each formed by laminating or mixing one or more hole injection / transport materials, or by a mixture of a hole injection / transport material and a polymer binder. In addition, an inorganic salt such as iron(III) chloride may be added to the hole injection / transport material to form a layer.

[0373] As a hole injection / transport material, it is necessary to efficiently inject and transport holes from the positive electrode between electrodes to which an electric field is applied. It is desirable that the hole injection efficiency is high and the injected holes are efficiently transported. For this purpose, it is preferable that the ionization potential is small, the hole mobility is large, the stability is excellent, and impurities that become traps are unlikely to occur during manufacturing and use.

[0374] As a material for forming the hole injection layer 103 and the hole transport layer 104, in a photoconductive material, any compound can be selected and used from compounds conventionally used as hole charge transport materials, p-type semiconductors, and known compounds used in the hole injection layer and the hole transport layer of an organic EL element. 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, polymers having an aromatic tertiary amino group in the 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-based 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, polysilane, etc. In the polymer system, polycarbonate, styrene derivatives, polyvinylcarbazole, and polysilane having the above monomer in the side chain are preferable, but it is not particularly limited as long as it is a compound that can form a thin film necessary for manufacturing a light-emitting element, can inject holes from the anode, and can further transport holes.

[0375] Also, it is known that the conductivity of an organic semiconductor is strongly affected by its 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 the doping of an electron-donating substance, strong electron acceptors such as tetracyanoquinodimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinodimethane (F4TCNQ) are known (for example, refer to 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 the electron transfer process in an electron-donating type base material (hole transport material). The conductivity of the base material changes significantly depending on the number and mobility of the holes. As matrix materials having hole transport characteristics, for example, benzidine derivatives (such as TPD) or starburst amine derivatives (such as TDATA), or specific metal phthalocyanines (especially zinc phthalocyanine (ZnPc), etc.) are known (Japanese Patent Laid-Open No. 2005-167175). The polycyclic aromatic compound of the present invention may be used as a material for forming a hole injection layer or a hole transport layer.

[0376] 2-1-6. Electron Blocking Layer in Organic Electroluminescent Element An electron blocking layer for preventing the diffusion of electrons from the light-emitting layer may be provided between the hole injection / transport layer and the light-emitting layer. For the formation of the electron blocking layer, the compounds represented by any of the above formulas (H1), (H2), and (H3) can be used. The polycyclic aromatic compound of the present invention may be used as a material for forming an electron blocking layer.

[0377] <Electron Injection Layer and Electron Transport Layer in Organic Electroluminescent Element> The electron injection layer 107 serves to efficiently inject electrons moving from the cathode 108 into the light-emitting layer 105 or the electron transport layer 106. The electron transport layer 106 serves to efficiently transport 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 or mixing one or more electron transport / injection materials, or by a mixture of an electron transport / injection material and a polymer binder.

[0378] The electron injection / transport layer is a layer that controls the injection and further transport of electrons from the cathode. It is desirable that the electron injection efficiency is high and the injected electrons can be efficiently transported. For this purpose, it is preferably a substance with a large electron affinity, a large electron mobility, excellent stability, and a low occurrence of trap impurities during manufacturing and use. However, when considering the transport balance of holes and electrons, if it mainly plays a role in efficiently preventing holes from the anode from flowing to the cathode without recombination, even if the electron transport ability is not so high, the effect of improving the light emission efficiency is equivalent to that of a material with a high electron transport ability. Therefore, the electron injection / transport layer in this embodiment may also include the function of a layer that can efficiently prevent the movement of holes.

[0379] As the material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107, it can be arbitrarily selected from compounds conventionally used as electron transfer compounds in photoconductive materials and known compounds used in the electron injection layer and the electron transport layer of organic EL elements.

[0380] As materials used for the electron transport layer or the electron injection layer, it is preferable to contain at least one selected from compounds composed of aromatic rings or heteroaromatic rings composed of one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon, and phosphorus, pyrrole derivatives and their condensed ring derivatives, and metal complexes having electron-accepting nitrogen. Specifically, condensed ring aromatic ring derivatives such as naphthalene and anthracene, styryl aromatic ring derivatives typified by 4,4'-bis(diphenylethenyl)biphenyl, perinone derivatives, coumarin derivatives, naphthalimide derivatives, quinone derivatives such as anthraquinone and diphenoquinone, phosphorus oxide derivatives, aryl nitrile derivatives, and indole derivatives can be mentioned. 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 mixed with different materials.

[0381] In addition, specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, fluoranthene derivatives, BO-based derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives (such as 1,3-bis[(4-t-butylphenyl)1,3,4-oxadiazolyl]phenylene), thiophene derivatives, triazole derivatives (such as N-naphthyl-2,5-diphenyl-1,3,4-triazole), thiadiazole derivatives, metal complexes of oxine derivatives, quinolinol-based metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives (such as 2,2’-bis(benzo[h]quinolin-2-yl)-9,9’-spirobifluorene), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (such as tris(N-phenylbenzimidazol-2-yl)benzene), benzoxazole derivatives, thiazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives, terpyridine derivatives (such as 1,3-bis(4’-(2,2’:6’,2”-terpyridinyl))benzene), naphthyridine derivatives (such as bis(1-naphthyl)-4-(1,8-naphthyridin-2-yl)phenylphosphine oxide), aldazine derivatives, pyrimidine derivatives, aryl nitrile derivatives, indole derivatives, phosphine oxide derivatives, bisstyryl derivatives, silole derivatives, and azoline derivatives, etc.

[0382] Moreover, metal complexes having electron-accepting nitrogen can also be used. For example, hydroxyazole complexes such as quinolinol-based metal complexes and hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes, etc.

[0383] The above-mentioned materials can be used alone or can be used by mixing with different materials.

[0384] Among the above-described materials, borane derivatives, pyridine derivatives, fluoranthene derivatives, BO-based derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, aryl nitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, quinolinol-based metal complexes, thiazole derivatives, benzothiazole derivatives, silole derivatives, and azoline derivatives are preferred.

[0385] The polycyclic aromatic compound of the present invention may be used as a material for forming an electron injection layer or an electron transport layer.

[0386] The electron transport layer or the electron injection layer may further contain a substance capable of reducing the material forming the electron transport layer or the electron injection layer. As long as this reducing substance has a certain reducing property, various substances can be used. For example, at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, oxides of alkali metals, halides of alkali metals, oxides of alkaline earth metals, halides of alkaline earth metals, oxides of rare earth metals, halides of rare earth metals, organic complexes of alkali metals, organic complexes of alkaline earth metals, and organic complexes of rare earth metals can be preferably used.

[0387] Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (same 2.28 eV), Rb (same 2.16 eV), or Cs (same 1.95 eV), and alkaline earth metals such as Ca (same 2.9 eV), Sr (same 2.0 - 2.5 eV), or Ba (same 2.52 eV). Substances with a work function of 2.9 eV or less are particularly preferred. Among these, more preferred reducing substances are alkali metals of K, Rb, or Cs, even more preferably Rb or Cs, and most preferably 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 electron injection layer, improvement in the emission luminance and extension of the lifetime in the organic EL element can be achieved. Also, as reducing substances with a work function of 2.9 eV or less, combinations of two or more of these alkali metals are also preferred, and in particular, combinations containing Cs, for example, combinations of Cs and Na, Cs and K, Cs and Rb, or combinations of Cs, Na, and K are preferred. By containing Cs, the reducing ability can be efficiently exerted, and by adding it to the material forming the electron transport layer or electron injection layer, improvement in the emission luminance and extension of the lifetime in the organic EL element can be achieved.

[0388] Furthermore, depending on the characteristics of the organic electroluminescent device, one or more organic layers such as a capping layer having various functions can be further included.

[0389] <Cathode in the organic electroluminescent device> The cathode 108 serves to inject electrons into the light-emitting layer 105 through the electron injection layer 107 and the electron transport layer 106.

[0390] The material for forming the cathode 108 is not particularly limited as long as it can efficiently inject electrons into the organic layer, and the same materials as those for 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 (such as magnesium-silver alloy, magnesium-indium alloy, aluminum-lithium alloy such as lithium fluoride / aluminum, etc.) are preferable. In order to improve the device characteristics by increasing the electron injection efficiency, lithium, sodium, potassium, cesium, calcium, magnesium, or alloys containing these low work function metals are effective. However, these low work function metals are generally often unstable in the atmosphere. To improve this point, for example, a method of doping a trace amount of lithium, cesium, or magnesium into the organic layer and using a highly stable electrode is known. Other dopants such as inorganic salts like lithium fluoride, cesium fluoride, lithium oxide, and cesium oxide can also be used. However, it is not limited to these.

[0391] Furthermore, for electrode protection, metals such as platinum, gold, silver, copper, iron, tin, aluminum, and indium, or alloys using these metals, and inorganic substances such as silica, titania, and silicon nitride, polyvinyl alcohol, vinyl chloride, hydrocarbon-based polymer compounds, etc. can be laminated, which are given as preferable examples. The manufacturing methods of these electrodes are also not particularly limited as long as conduction can be achieved, such as resistance heating, electron beam evaporation, sputtering, ion plating, and coating.

[0392] <Binder that may be used in each layer> The materials used for the above hole injection layer, hole transport layer, light-emitting layer, electron transport layer, and electron injection layer can form each layer alone. However, they can also be dispersed and used in solvent-soluble resins such as 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, etc., or curable resins such as phenol resin, xylene resin, petroleum resin, urea resin, melamine resin, unsaturated polyester resin, alkyd resin, epoxy resin, silicone resin, etc.

[0393] <Composition for forming organic layer used in wet film-forming method> The composition for forming an organic layer is obtained by dissolving a low-molecular compound capable of forming each organic layer of the organic EL element, or a polymer compound obtained by polymerizing the low-molecular compound, in an organic solvent. For example, the composition for forming a light-emitting layer contains, as a first component, at least one polycyclic aromatic compound (or its polymer compound) that is a dopant material, as a second component, at least one host material, and as a third component, at least one organic solvent. The first component functions as a dopant component of the light-emitting layer obtained from the composition, and the second component functions as a host component of the light-emitting layer. The third component functions as a solvent for dissolving the first and second components in the composition, and provides a smooth and uniform surface shape during coating due to the controlled evaporation rate of the third component itself.

[0394] <Organic solvent> The composition for forming an organic layer contains at least one organic solvent. By controlling the evaporation rate of the organic solvent during film formation, the film-forming property, the presence or absence of defects in the coating film, the surface roughness, and the smoothness can be controlled and improved. Further, during film formation using the inkjet method, the meniscus stability at the pinholes of the inkjet head can be controlled, and the ejection property can be controlled and improved. In addition, by controlling the drying rate of the film and the orientation of the derivative molecules, the electrical characteristics, light-emitting characteristics, efficiency, and lifespan of the organic EL element having an organic layer obtained from the composition for forming an organic layer can be improved.

[0395] (1) Physical properties of the organic solvent The boiling point of at least one organic solvent is 130°C to 300°C, more preferably 140°C to 270°C, and even more preferably 150°C to 250°C. When the boiling point is higher than 130°C, it is preferable from the viewpoint of the ejection property of the inkjet. Further, when the boiling point is lower than 300°C, it is preferable from the viewpoints of defects in the coating film, surface roughness, residual solvent, and smoothness. The organic solvent preferably contains two or more organic solvents from the viewpoints of good inkjet ejection property, film-forming property, smoothness, and low residual solvent. On the other hand, in some cases, considering transportability and the like, a composition in a solid state may be obtained by removing the solvent from the composition for forming an organic layer.

[0396] Furthermore, the organic solvent contains a good solvent (GS) and a poor solvent (PS) for at least one of the solutes, and a configuration in which the boiling point (BP GS ) of the good solvent (GS) is lower than the boiling point (BP PS ) of the poor solvent (PS) is particularly preferable. By adding a high-boiling poor solvent, the low-boiling good solvent volatilizes first during film formation, the concentration of the contents in the composition and the concentration of the poor solvent increase, and rapid film formation is promoted. As a result, a coating film with few defects, small surface roughness, and high smoothness can be obtained.

[0397] The difference in solubility (S GS -S PS ) is preferably 1% or more, more preferably 3% or more, and even more preferably 5% or more. The difference in boiling point (BP PS-BP GS ) is preferably 10 °C or higher, more preferably 30 °C or higher, and even more preferably 50 °C or higher.

[0398] The organic solvent is removed from the coating film by a drying process such as vacuum, reduced pressure, heating, etc. after film formation. When heating is performed, from the viewpoint of improving coating film formability, it is preferably performed at a temperature of at least one glass transition temperature (Tg) of the solute + 30 °C or lower. Also, from the viewpoint of reducing the residual solvent, it is preferably heated at a temperature of at least one glass transition point (Tg) of the solute - 30 °C or higher. Even if the heating temperature is lower than the boiling point of the organic solvent, the organic solvent is sufficiently removed because the film is thin. Also, drying may be performed multiple times at different temperatures, or a plurality of drying methods may be used in combination.

[0399] (2) Specific examples of the organic solvent Examples of the organic solvent used in the composition for forming the organic layer include alkylbenzene solvents, phenyl ether solvents, alkyl ether solvents, cyclic ketone solvents, aliphatic ketone solvents, monocyclic ketone solvents, solvents having a diester skeleton, and fluorine-containing solvents. Specific examples include pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tetradecanol, hexan-2-ol, heptan-2-ol, octan-2-ol, decan-2-ol, dodecan-2-ol, cyclohexanol, α-terpineol, β-terpineol, γ-terpineol, δ-terpineol, terpineol (mixture), ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol isopropyl methyl ether, dipropylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol butyl methyl ether, tripropylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, ethylene glycol monophenyl ether, triethylene glycol monomethyl ether, diethylene glycol dibutyl ether, triethylene glycol butyl methyl ether, polyethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, p-xylene, m-xylene, o-xylene, 2,6-lutidine, 2-fluoro-m-xylene, 3-fluoro-o-xylene, 2-chlorobenzotrifluoride, cumene, toluene, 2-chloro-6-fluorotoluene, 2-fluoroanisole, anisole, 2,3-dimethylpyrazine, bromobenzene, 4-fluoroanisole, 3-fluoroanisole, 3-trifluoromethylanisole, mesitylene, 1,2,4-trimethylbenzene, t-butylbenzene, 2-methylanisole, phenetole, benzodioxole, 4-methylanisole, s-butylbenzene, 3-methylanisole, 4-fluoro-3-methylanisole, cymene, 1,2,3-trimethylbenzene, 1,2-dichlorobenzene, 2-fluorobenzonitrile, 4-fluoroveratrole, 2,6-dimethylanisole, n-butylbenzene, 3-fluorobenzonitrile, decalin (decalin), neopentylbenzene, 2,5-dimethylanisole, 2,4-dimethylanisole, benzonitrile, 3,5-dimethylanisole, diphenyl ether, 1-fluoro-3,5-dimethoxybenzene, methyl benzoate, isopentylbenzene, 3,4-dimethylanisole, o-tolunitrile, n-amylbenzene, veratrole, 1,2,3,4-tetrahydronaphthalene, ethyl benzoate, n-hexylbenzene, propyl benzoate, cyclohexylbenzene, 1-methylnaphthalene, butyl benzoate, 2-methylbiphenyl, 3-phenoxytoluene, 2,2'-bipyridyl, dodecylbenzene, dipentylbenzene, tetramethylbenzene, trimethoxybenzene, trimethoxytoluene, 2,3-dihydrobenzofuran, 1-methyl-4-(propoxymethyl)benzene, 1-methyl-4-(butyloxymethyl)benzene, 1-methyl-4-(pentyloxymethyl)benzene, 1-methyl-4-(hexyloxymethyl)benzene, 1-methyl-4-(heptyloxymethyl)benzene benzyl butyl ether, benzyl pentyl ether, benzyl hexyl ether, benzyl heptyl ether, benzyl octyl ether, etc., but not limited thereto. Further, the solvent may be used alone or in combination.,

[0400] <Optional component> The composition for forming an organic layer may contain an optional component as long as its properties are not impaired. Examples of the optional component include a binder and a surfactant.,

[0401] (1) Binder The composition for forming an organic layer may contain a binder. The binder forms a film during film formation and bonds the obtained film to the substrate. Further, it plays a role of dissolving, dispersing, and binding other components in the composition for forming an organic layer.,

[0402] Examples of binders used in the composition for forming the organic layer include, but are not limited to, acrylic resins, polyethylene terephthalate, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, acrylonitrile-ethylene-styrene copolymer (AES) resins, ionomers, chlorinated polyethers, diallyl phthalate resins, unsaturated polyester resins, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, Teflon, acrylonitrile-butadiene-styrene copolymer (ABS) resins, acrylonitrile-styrene copolymer (AS) resins, phenolic resins, epoxy resins, melamine resins, urea resins, alkyd resins, polyurethanes, and copolymers of the above resins and polymers.

[0403] The binder used in the composition for forming the organic layer may be only one type or a mixture of multiple types.

[0404] (2) Surfactant The composition for forming the organic layer may contain a surfactant, for example, for controlling the film surface uniformity of the composition for forming the organic layer, the hydrophilicity of the film surface, and the liquid repellency. Surfactants are classified into ionic and non-ionic types based on the structure of the hydrophilic group, and further classified into alkyl-based, silicon-based, and fluorine-based types based on the structure of the hydrophobic group. Also, from the molecular structure, they are classified into single-molecule systems having a relatively small molecular weight and a simple structure and polymer systems having a large molecular weight and side chains or branches. Also, from the composition, they are classified into single-component systems and mixed systems in which two or more surfactants and a substrate are mixed. As the surfactant that can be used in the composition for forming the organic layer, all types of surfactants can be used.

[0405] Examples of surfactants include Polyflow No. 45, Polyflow KL-245, Polyflow No. 75, Polyflow No. 90, Polyflow No. 95 (trade names, manufactured by Kyoeisha Chemical Co., Ltd.), Disperbyk 161, Disperbyk 162, Disperbyk 163, Disperbyk 164, Disperbyk 166, Disperbyk 170, Disperbyk 180, Disperbyk 181, Disperbyk 182, BYK300, BYK306, BYK310, BYK320, BYK330, BYK342, BYK344, BYK346 (trade names, manufactured by BYK-Chemie Japan Co., Ltd.), KP-341, KP-358, KP-368, KF-96-50CS, KF-50-100CS (trade names, manufactured by Shin-Etsu Chemical Co., Ltd.), Surflon SC-101, Surflon KH-40 (trade names, manufactured by Seimi Chemical Co., Ltd.), Ftergent 222F, Ftergent 251, FTX-218 (trade names, manufactured by Neos Co., Ltd.), EFTOP EF-351, EFTOP EF-352, EFTOP EF-601, EFTOP EF-801, EFTOPEF-802 (trade name, manufactured by Mitsubishi Materials Corporation), Megafac F-470, Megafac F-471, Megafac F-475, Megafac R-08, Megafac F-477, Megafac F-479, Megafac F-553, Megafac F-554 (trade name, manufactured by DIC Corporation), fluoroalkylbenzenesulfonate, fluoroalkyl carboxylate, fluoroalkyl polyoxyethylene ether, fluoroalkylammonium iodide, fluoroalkyl betaine, fluoroalkyl sulfonate, diglycerin tetrakis(fluoroalkyl polyoxyethylene ether), fluoroalkyl trimethylammonium salt, fluoroalkylaminosulfonate, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene laurate, polyoxyethylene oleate, polyoxyethylene stearate, polyoxyethylene laurylamine, sorbitan laurate, sorbitan palmitate, sorbitan stearate, sorbitan oleate, sorbitan fatty acid ester, polyoxyethylene sorbitan laurate, polyoxyethylene sorbitan palmitate, polyoxyethylene sorbitan stearate, polyoxyethylene sorbitan oleate, polyoxyethylene naphthyl ether, alkylbenzenesulfonate and alkyldiphenyl ether disulfonate can be mentioned.

[0406] In addition, the surfactant may be used alone or in combination of two or more.

[0407] <Composition and Physical Properties of Composition for Forming Organic Layer> The content of each component in the composition for forming an organic layer is determined in consideration of the good solubility, storage stability, and film-forming property of each component in the composition for forming an organic layer, the high-quality film quality of the coating film obtained from the composition for forming an organic layer, the good ejection property when using the inkjet method, and the good electrical characteristics, light-emitting characteristics, efficiency, and lifespan of the organic EL element having an organic layer produced using the composition. For example, in the case of the composition for forming a light-emitting layer, the first component is preferably 0.0001% by mass to 2.0% by mass based on the total mass of the composition for forming a light-emitting layer, the second component is preferably 0.0999% by mass to 8.0% by mass based on the total mass of the composition for forming a light-emitting layer, and the third component is preferably 90.0% by mass to 99.9% by mass based on the total mass of the composition for forming a light-emitting layer.

[0408] More preferably, the first component is 0.005% by mass to 1.0% by mass based on the total mass of the composition for forming a light-emitting layer, the second component is 0.095% by mass to 4.0% by mass based on the total mass of the composition for forming a light-emitting layer, and the third component is 95.0% by mass to 99.9% by mass based on the total mass of the composition for forming a light-emitting layer. Even more preferably, the first component is 0.05% by mass to 0.5% by mass based on the total mass of the composition for forming a light-emitting layer, the second component is 0.25% by mass to 2.5% by mass based on the total mass of the composition for forming a light-emitting layer, and the third component is 97.0% by mass to 99.7% by mass based on the total mass of the composition for forming a light-emitting layer.

[0409] The composition for forming an organic layer can be produced by appropriately selecting known methods such as stirring, mixing, heating, cooling, dissolving, and dispersing the above-described components. Further, after preparation, filtration, degassing (also referred to as degas), ion exchange treatment, and inert gas substitution / encapsulation treatment may be appropriately selected and performed.

[0410] As for the viscosity of the composition for forming an organic layer, a higher viscosity provides better film-forming properties and better ejection properties when using the inkjet method. On the other hand, a lower viscosity makes it easier to form a thin film. Therefore, the viscosity of the composition for forming an organic layer preferably has a viscosity at 25°C of 0.3 to 3 mPa·s, more preferably 1 to 3 mPa·s. In the present invention, the viscosity is a value measured using a cone-plate type rotational viscometer (cone plate type).

[0411] As for the surface tension of the composition for forming an organic layer, a lower surface tension provides better film-forming properties and a defect-free coating film. On the other hand, a higher surface tension provides better inkjet ejection properties. Therefore, the viscosity of the composition for forming an organic layer preferably has a surface tension at 25°C of 20 to 40 mN / m, more preferably 20 to 30 mN / m. In the present invention, the surface tension is a value measured using the sessile drop method.

[0412] <Crosslinkable polymer compound: a compound represented by formula (XLP-1)> Next, the case where the above-described polymer compound has a crosslinkable substituent will be described. Such a crosslinkable polymer compound is, for example, a compound represented by the following formula (XLP-1).

[0413] [Chemical formula]

[0414] In formula (XLP-1), MUx, ECx and k have the same definitions as MU, EC and k in formula (SPH-1), provided that the compound represented by formula (XLP-1) has at least one crosslinkable substituent (XLS), and preferably the content of the monovalent or divalent aromatic group having a crosslinkable substituent is 0.1 to 80% by mass in the molecule.

[0415] The content of the monovalent or divalent aromatic compound having a crosslinkable substituent is preferably 0.5 to 50% by mass, more preferably 1 to 20% by mass.

[0416] The crosslinkable substituent (XLS) is not particularly limited as long as it is a group capable of further crosslinking the above-described polymer compound, but substituents having the following structures are preferred. * in each structural formula indicates the bonding position.

Chemical formula

[0417] L is, independently of each other, a single bond, -O-, -S-, >C=O, -O-C(=O)-, alkylene having 1 to 12 carbon atoms, oxyalkylene having 1 to 12 carbon atoms, and polyoxyalkylene having 1 to 12 carbon atoms. Among the above substituents, groups represented by formula (XLS-1), formula (XLS-2), formula (XLS-3), formula (XLS-9), formula (XLS-10) or formula (XLS-17) are preferred, and groups represented by formula (XLS-1), formula (XLS-3) or formula (XLS-17) are more preferred.

[0418] Examples of the divalent aromatic compound having a crosslinkable substituent include compounds having the following partial structures.

Chemical formula

[0419]

Chemical formula

[0420]

Chemical formula

[0421]

Chemical formula

[0422] <Method for Producing Polymer Compound and Crosslinkable Polymer Compound> Regarding the production methods of high molecular compounds and crosslinkable high molecular compounds, the compounds represented by the above-mentioned formula (SPH-1) and the compound represented by (XLP-1) will be described as examples. These compounds can be synthesized by appropriately combining known production methods.

[0423] Examples of the solvent used in the reaction include aromatic solvents, saturated / unsaturated hydrocarbon solvents, alcohol solvents, ether solvents, etc., such as dimethoxyethane, 2-(2-methoxyethoxy)ethane, 2-(2-ethoxyethoxy)ethane, etc.

[0424] Also, the reaction may be carried out in a two-phase system. When reacting in a two-phase system, a phase transfer catalyst such as a quaternary ammonium salt may be added as necessary.

[0425] When producing the compound of formula (SPH-1) and the compound of (XLP-1), it may be produced in one step or through multiple steps. Also, it may be carried out by a batch polymerization method in which all the raw materials are put into the reaction vessel and then the reaction is started, or by a dropwise polymerization method in which the raw materials are added dropwise to the reaction vessel, or by a precipitation polymerization method in which the product precipitates as the reaction progresses, and these can be appropriately combined for synthesis. For example, when synthesizing the compound represented by formula (SPH-1) in one step, the target product is obtained by carrying out the reaction with a monomer having a polymerizable group bonded to the monomer unit (MU) and a monomer having a polymerizable group bonded to the end cap unit (EC) added to the reaction vessel. Also, when synthesizing the compound represented by formula (SPH-1) in multiple steps, after polymerizing a monomer having a polymerizable group bonded to the monomer unit (MU) to the target molecular weight, a monomer having a polymerizable group bonded to the end cap unit (EC) is added and reacted to obtain the target product. By adding and reacting monomers having polymerizable groups bonded to different types of monomer units (MU) in multiple steps, a polymer having a concentration gradient in the structure of the monomer unit can be produced. Also, after preparing a precursor polymer, the target product polymer can be obtained by subsequent reaction.

[0426] Moreover, by selecting the polymerizable groups of the monomers, the primary structure of the polymer can be controlled. For example, as shown in Synthesis Schemes 1 to 3, it is possible to synthesize polymers having a random primary structure (Synthesis Scheme 1), polymers having a regular primary structure (Synthesis Schemes 2 and 3), etc., and they can be appropriately combined and used according to the target product. Furthermore, by using monomer units having three or more polymerizable groups, hyperbranched polymers or dendrimers can be synthesized.

[0427] [Chemical formula]

[0428] The monomers that can be used in the present invention can be synthesized according to the methods described in JP-A No. 2010-189630, WO 2012 / 086671, WO 2013 / 191088, WO 2002 / 045184, WO 2011 / 049241, WO 2013 / 146806, WO 2005 / 049546, WO 2015 / 145871, JP-A No. 2010-215886, JP-A No. 2008-106241, JP-A No. 2010-215886, WO 2016 / 031639, JP-A No. 2011-174062, WO 2016 / 031639, WO 2016 / 031639, WO 2002 / 045184.

[0429] Regarding the specific polymer synthesis procedure, it can be synthesized according to the methods described in JP-A No. 2012-036388, WO 2015 / 008851, JP-A No. 2012-36381, JP-A No. 2012-144722, WO 2015 / 194448, WO 2013 / 146806, WO 2015 / 145871, WO 2016 / 031639, WO 2016 / 125560, WO 2016 / 031639, WO 2016 / 031639, WO 2016 / 125560, WO 2015 / 145871, WO 2011 / 049241, and JP-A No. 2012-144722.

[0430] <Method for manufacturing an organic electroluminescent element> Each layer constituting the organic EL element can be formed by forming a thin film of the material to constitute each layer by a method such as vapor deposition method, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination method, printing method, inkjet method, spin coating method, casting method, or coating method. There is no particular limitation on the film thickness of each layer thus formed, and it can be appropriately set according to the properties of the material, but it is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured with a crystal oscillator type film thickness measuring device or the like. When thinning by the vapor deposition method, the vapor deposition conditions vary depending on the type of material, the intended crystal structure and association structure of the film, etc. The vapor deposition conditions are generally preferably set as appropriate in the range of boat heating temperature +50 to +400 °C, degree of vacuum 10 -6 ~10 -3 Pa, vapor deposition rate 0.01 to 50 nm / second, substrate temperature -150 to +300 °C, and film thickness 2 nm to 5 μm.

[0431] Next, as an example of a method for manufacturing an organic EL element, a method for manufacturing an organic EL element composed of an anode / hole injection layer / hole transport layer / light-emitting layer composed of a host material and a dopant material / electron transport layer / electron injection layer / cathode will be described. After forming a thin film of an anode material on a suitable substrate by a vapor deposition method or the like to fabricate an anode, thin films of a hole injection layer and a hole transport layer are formed on this anode. A host material and a dopant material are co-evaporated thereon to form a thin film as a light-emitting layer, an electron transport layer and an electron injection layer are formed on this light-emitting layer, and further a thin film made of a cathode material is formed by a vapor deposition method or the like to form a cathode, whereby the target organic EL element can be obtained. In addition, in the fabrication of the above-described organic EL element, it is also possible to fabricate in the reverse order of fabrication, that is, in the order of cathode, electron injection layer, electron transport layer, light-emitting layer, hole transport layer, hole injection layer, and anode.

[0432] When a DC voltage is applied to the organic EL element thus obtained, it may be applied with the anode being the positive polarity and the cathode being the negative polarity. When a voltage of about 2 to 40 V is applied, light emission can be observed from the transparent or semi-transparent electrode side (anode or cathode, and both). Further, this organic EL element also emits light when a pulse current or an alternating current is applied. Note that the waveform of the applied alternating current may be arbitrary.

[0433] <Application Examples of Organic Electroluminescent Elements> The organic EL element can also be applied to a display device or a lighting device. A display device or a lighting device provided with an organic EL element can be manufactured by a known method such as connecting the organic EL element and a known driving device, and can be driven by appropriately using a known driving method such as DC driving, pulse driving, or AC driving.

[0434] Examples of the display device include panel displays such as color flat panel displays, and flexible displays such as flexible color organic electroluminescence (EL) displays (see, for example, Japanese Patent Application Laid-Open No. 10-335066, Japanese Patent Application Laid-Open No. 2003-321546, Japanese Patent Application Laid-Open No. 2004-281086, etc.). Examples of the display method of the display include matrix and / or segment methods. Note that matrix display and segment display may coexist in the same panel.

[0435] In a matrix, pixels for display are two-dimensionally arranged in a lattice or mosaic pattern, and characters and images are displayed by a set of pixels. The shape and size of the pixels are determined by the application. For example, for image and character display of personal computers, monitors, and televisions, square pixels with a side length of usually 300 μm or less are generally used. In the case of a large display such as a display panel, pixels with a side length on the order of mm are used. In the case of monochrome display, pixels of the same color may be arranged. In the case of color display, red, green, and blue pixels are arranged for display. In this case, typically, there are delta type and stripe type. As the driving method of this matrix, either a line sequential driving method or an active matrix may be used. The line sequential driving has the advantage of a simple structure, but considering the operating characteristics, the active matrix may be superior in some cases, so it is also necessary to use them appropriately depending on the application.

[0436] In the segment method (type), a pattern is formed to display predetermined information, and a predetermined area is made to emit light. For example, time and temperature display in digital clocks and thermometers, operation state display in audio equipment and electromagnetic cookers, and panel display in automobiles, etc. can be cited.

[0437] Examples of the lighting device include lighting devices such as indoor lighting, and backlights for liquid crystal display devices (see, for example, Japanese Patent Application Laid-Open Nos. 2003-257621, 2003-277741, 2004-119211, etc.). The backlight is mainly used for the purpose of improving the visibility of a display device that does not emit light by itself, and is used for liquid crystal display devices, watches, audio devices, automotive panels, display boards, signs, and the like. In particular, as a backlight for a liquid crystal display device, especially for a personal computer application where thinning is an issue, considering that it is difficult to thin the conventional method consisting of a fluorescent lamp and a light guide plate, the backlight using an organic EL element is characterized by being thin and lightweight.

[0438] <Other organic devices> In addition to the above-described organic electroluminescent element, the polycyclic aromatic compound according to the present invention can be used for the production of an organic field effect transistor or an organic thin film solar cell.

[0439] An organic field effect transistor is a transistor that controls current by an electric field generated by a voltage input, and a gate electrode is provided 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 it is a transistor that can arbitrarily block the flow of electrons (or holes) flowing between the source electrode and the drain electrode to control the current. The field effect transistor is easier to miniaturize than a simple transistor (bipolar transistor), and is often used as an element constituting an integrated circuit or the like.

[0440] The structure of the organic field effect transistor usually has a source electrode and a drain electrode provided in contact with an organic semiconductor active layer formed using the polycyclic aromatic compound according to the present invention, and a gate electrode may be provided with an insulating layer (dielectric layer) in contact with the organic semiconductor active layer interposed therebetween. Examples of the element structure include the following structures. (1) Substrate / Gate electrode / Insulator layer / Source electrode · Drain electrode / Organic semiconductor active layer (2) Substrate / Gate electrode / Insulator layer / Organic semiconductor active layer / Source electrode · 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 as described above can be applied as a pixel drive switching element for a liquid crystal display or an organic electroluminescence display using an active matrix drive method, etc.

[0441] The 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 the hole transport layer, p-type semiconductor layer, n-type semiconductor layer, and electron transport layer according to 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. Known materials used for organic thin film solar cells can be appropriately selected and combined for use in the organic thin film solar cell.

[0442] <Wavelength conversion material> The polycyclic aromatic compound of the present invention can be used as a wavelength conversion material. Currently, the application of multi-color technology based on color conversion methods to liquid crystal displays, organic EL displays, lighting, etc. is being actively studied. Color conversion means converting the light emitted from a light emitter into light with a longer wavelength. For example, it represents converting ultraviolet light or blue light into green light or red light emission. 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. Using such a white light source that combines 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 makes it possible to fabricate a full-color display. Also, if there is no liquid crystal driving part, it can be used directly as a white light source and applied as a white light source for, for example, LED lighting. Further, by using a blue organic EL element as a light source and combining it with a wavelength conversion film that converts blue light into green light and red light, it becomes possible to fabricate a full-color organic EL display without using a metal mask. Furthermore, by using a blue micro LED as a light source and combining it with a wavelength conversion film that converts blue light into green light and red light, it becomes possible to fabricate a low-cost full-color micro LED display.

[0443] The polycyclic aromatic compound of the present invention can be used as this wavelength conversion material. Using a 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 blue light with a shorter wavelength can be converted into blue light or green light with high color purity suitable for use in a display device (a display device using an organic EL element or a liquid crystal display device). Adjustment of the color to be converted can be performed by appropriately selecting the substituents of the polycyclic aromatic compound of the present invention, the binder resin used in the wavelength conversion composition described later, etc. The wavelength conversion material can be prepared as a wavelength conversion composition containing the polycyclic aromatic compound of the present invention. Also, a wavelength conversion film may be formed using this wavelength conversion composition.

[0444] The wavelength conversion composition may contain, in addition to the polycyclic aromatic compound of the present invention, a binder resin, other additives, and a solvent. 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, the compounds described in paragraphs 0177 to 0181 of International Publication No. 2016 / 190283 can be used. As the solvent, reference can be made to the description of the solvent contained in the above-described composition for forming a light-emitting layer.

[0445] The wavelength conversion film includes a wavelength conversion layer formed by curing the wavelength conversion composition. As a method for producing the wavelength conversion layer from the wavelength conversion composition, a known film formation 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, or may include other wavelength conversion layers (for example, a wavelength conversion layer that converts blue light into green light or red light, a wavelength conversion layer that converts blue light or green light into red light). Further, the wavelength conversion film may include a substrate layer or a barrier layer for preventing deterioration of the color conversion layer due to oxygen, moisture, or heat.

Examples

[0446] Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited thereto. First, a synthesis example of the polycyclic aromatic compound will be described below.

[0447] Synthesis Example (1): Synthesis of Compound (1-2) To a flask containing compound (Int-1-2) (2.4 g, 3.0 mmol, 1 eq.) and tert-butylbenzene ( t Bu-benzene, 50 ml), at 0 °C under a nitrogen atmosphere, a 1.60 M solution of tert-butyllithium in pentane ( tn-BuLi (3.75 mL) was added. After completion of the dropwise addition, the temperature was raised to 70 °C and the mixture was stirred for 0.5 h. Then, components with boiling points lower than tert-butylbenzene were distilled off under reduced pressure. The mixture was cooled to -50 °C and boron tribromide (0.62 g) was added. The temperature was raised to room temperature and the mixture was stirred for 0.5 h. Then, it was cooled to 0 °C again and N,N-diisopropylethylamine (EtN i Pr2, 0.39 g) was added. After stirring at room temperature until the exothermic reaction subsided, the temperature was raised to 100 °C and the mixture was heated and stirred for 1 h. The reaction solution was cooled to room temperature, an aqueous sodium acetate solution cooled in an ice bath was added, and then ethyl acetate was added for liquid separation. After concentration of the organic layer, it was purified by a silica gel short path column (eluent: chlorobenzene). The obtained crude product was recrystallized from toluene to obtain compound (1-2) (0.20 g). By MS, the target compound (1-2) was confirmed at m / z (M+H) = 773.501.

Chemical formula

[0448] Synthesis Example (2): Synthesis of Compound (1-31) Compound (1-31) (0.13 g) was obtained in the same procedure as in Synthesis Example 1, except that compound (Int-1-2) (2.40 g, 3.0 mmol, 1 eq.) was changed to compound (Int-1-31) (2.40 g, 3.0 mmol, 1 eq.). By MS, the target compound (1-31) was confirmed at m / z (M+H) = 773.501.

Chemical formula

[0449] Synthesis Example (3): Synthesis of Compound (1-44) Compound (1-44) (0.16 g) was obtained in the same procedure as in Synthesis Example 1, except that compound (Int-1-2) (2.40 g, 3.0 mmol, 1 eq.) was changed to compound (Int-1-44) (2.40 g, 3.0 mmol, 1 eq.). By MS, the target compound (1-44) was confirmed at m / z (M+H) = 773.501. [Chemical formula]

[0450] Synthesis Example (4): Synthesis of Compound (1-71) Into a flask containing Compound (Int-1-71) (2.88 g, 3.0 mmol, 1 eq.) and tert-butylbenzene ( t Bu-benzene, 50 ml), under a nitrogen atmosphere at 0 °C, a 1.60 M solution of tert-butyllithium in pentane ( t BuLi, 7.50 ml) was added. After completion of the dropwise addition, the temperature was raised to 70 °C and stirred for 0.5 hour, then the components with lower boiling points than tert-butylbenzene were distilled off under reduced pressure. After cooling to -50 °C, boron tribromide (1.23 g) was added, the temperature was raised to room temperature and stirred for 0.5 hour. Then, it was cooled to 0 °C again, N,N-diisopropylethylamine (EtN i Pr2, 0.78 g) was added, stirred at room temperature until the exothermic reaction subsided, then the temperature was raised to 100 °C and heated with stirring for 1 hour. The reaction solution was cooled to room temperature, an aqueous sodium acetate solution cooled in an ice bath was added, and then ethyl acetate was added for liquid separation. After concentrating the organic layer, it was purified by a silica gel short-path column (eluent: chlorobenzene). The obtained crude product was recrystallized from toluene to obtain Compound (1-71) (0.26 g). Compound (1-71), the target compound, was confirmed by MS at m / z (M+H) = 907.320. [Chemical formula]

[0451] Synthesis Example (5): Synthesis of Compound (1-73) Compound (1-73) (0.09 g) was obtained in the same procedure as in Synthesis Example 4, except that Compound (Int-1-71) (2.88 g, 3.0 mmol, 1 eq.) was changed to Compound (Int-1-73) (2.88 g, 3.0 mmol, 1 eq.). Compound (1-73), the target compound, was confirmed by MS at m / z (M+H) = 907.320.

Chem.

[0452] Synthesis Example (6): Synthesis of Compound (1-81) Compound (1-81) (0.21 g) was obtained in the same procedure as in Synthesis Example 4, except that compound (Int-1-71) (2.88 g, 3.0 mmol, 1 eq.) was changed to compound (Int-1-81) (2.88 g, 3.0 mmol, 1 eq.). The target compound (1-81) was confirmed by MS at m / z (M+H) = 907.320.

Chem.

[0453] Synthesis of Comparative Compound (1) It was synthesized according to the method described in Korean Patent Publication No. 2020 / 121228. The target comparative compound (1) was confirmed by MS at m / z (M+H) = 775.516.

Chem.

[0454] By appropriately changing the starting compounds, other polycyclic aromatic compounds of the present invention can be synthesized by the method according to the above-described synthesis examples.

[0455] Next, the fabrication and evaluation of an organic EL device using the compound of the present invention will be described. However, the application of the compound of the present invention is not limited to the examples shown below, and the film thickness and constituent materials of each layer can be appropriately changed depending on the basic physical properties of the compound of the present invention.

[0456] Evaluation Items and Evaluation Methods The evaluation items include driving voltage (V), emission wavelength (nm), CIE chromaticity (x, y), external quantum efficiency (%), maximum wavelength (nm) and full width at half maximum (nm) of the emission spectrum, etc. For these evaluation items, values at an appropriate emission luminance can be used.

[0457] The quantum efficiency of a light-emitting device includes an internal quantum efficiency and an external quantum efficiency. The internal quantum efficiency indicates the ratio at which external energy injected as electrons (or holes) into the light-emitting layer of the light-emitting device is purely converted into photons. On the other hand, the external quantum efficiency is calculated based on the amount of photons emitted to the outside of the light-emitting device. Since some of the photons generated in the light-emitting layer are absorbed or continuously reflected inside the light-emitting device and are not emitted to the outside of the light-emitting device, the external quantum efficiency is lower than the internal quantum efficiency.

[0458] The measurement methods for spectral radiance (emission spectrum) and external quantum efficiency are as follows. Using a voltage / current generator R6144 manufactured by Advantest, the device was made to emit light by applying a voltage. Using a spectral radiance meter SR-3AR manufactured by TOPCON, the spectral radiance in the visible light region was measured from the perpendicular direction to the light-emitting surface. Assuming that the light-emitting surface is a perfect diffusing surface, the value obtained by dividing the measured spectral radiance value of each wavelength component by the wavelength energy and multiplying by π is the number of photons at each wavelength. Next, the number of photons was integrated over the entire observed wavelength region to obtain the total number of photons emitted from the device. The value obtained by dividing the total number of photons emitted from the device by the number of carriers injected into the device, where the value obtained by dividing the applied current value by the elementary charge is taken as the number of carriers injected into the device, is the external quantum efficiency. Also, the full width at half maximum of the emission spectrum is obtained as the width between the upper and lower wavelengths at which the intensity becomes 50% centered on the peak emission wavelength.

[0459] <Evaluation of Vacuum Deposition-Type Organic EL Devices> Organic EL devices according to Examples 1-1 to 1-6 and Comparative Example 1-1 were fabricated, and the driving voltage, external quantum efficiency (EQE), and LT50 (the time to maintain 50% or more of the luminance during constant current driving. In this case, when continuously driven at the current density at an initial luminance of 500 cd / m 2 the time to maintain a luminance of 250 cd / m 2 or more) were measured. 2

[0460] [Table 1]​

[0461] The chemical structures of "NPD", "TcTa", "mCP", "Ir(ppy)3", "2CzBN", "BPy-TP2", "GH-1", and Comparative Compound (1) in Table 1 are shown below.

[0462]

Chemical formula

[0463] <Example 1-1> A 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Opto Science Co., Ltd.) with ITO film formed by sputtering and polished to a thickness of 200 nm to 50 nm was used as a transparent support substrate. This transparent support substrate was fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and molybdenum vapor deposition boats containing NPD, TcTa, mCP, GH-1, Compound (1-2), 2CzBN, and BPy-TP2, and tungsten vapor deposition boats containing LiF and aluminum were installed.

[0464] The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was 5 × 10 -4The pressure was reduced to Pa. First, NPD was heated and evaporated to a thickness of 40 nm to form a hole injection layer. Next, TcTa was heated and evaporated to a thickness of 15 nm, and then mCP was heated and evaporated to a thickness of 15 nm to form a two-layer hole transport layer. Next, GH-1 and compound (1-2) were simultaneously heated and evaporated to a thickness of 20 nm to form a light-emitting layer. The evaporation rate was adjusted so that the weight ratio of GH-1 to compound (1-2) was approximately 99 to 1. Next, 2CzBN was heated and evaporated to a thickness of 10 nm, and then BPy-TP2 was heated and evaporated to a thickness of 20 nm to form a two-layer electron transport layer. The evaporation rate of each layer was 0.01 - 1 nm / second. Then, LiF was heated and evaporated at an evaporation rate of 0.01 - 0.1 nm / second to a thickness of 1 nm, and then aluminum was heated and evaporated to a thickness of 100 nm to form a cathode, obtaining an organic EL element. At this time, the evaporation rate of aluminum was adjusted to be 1 - 10 nm / second.

[0465] <Examples 1-2 to 1-6, Comparative Example 1-1> The compound (1-2), which is the dopant of Example 1, was changed to each dopant described in Table 1 to fabricate each element.

[0466] The evaluation results of each element are shown in Table 2.

Table 2

[0467] In Examples 1-1 to 1-6, higher external quantum efficiency and longer LT50 were obtained compared to Comparative Example 1-1.

[0468] <Evaluation of Vapor Deposition-Type Organic EL Elements> Organic EL elements according to Examples G2-1 to G2-6, Comparative Example G2-1, Examples G3-1 to G3-6, and Comparative Example G3-1 were fabricated, and the emission wavelength, full width at half maximum, driving voltage, external quantum efficiency, and LT50 (the time to maintain 50% or more of the luminance during constant current driving, in this case, the time to maintain a luminance of 250 cd / m 2 at an initial luminance of 500 cd / m 2 when continuously driven at the current density at 2 and above) were measured.

[0469]

Table 3

[0470] The chemical structures of "HATCN", "TBB", "CBP", and "GH-2" are shown below.

[0471]

Chemical Formula

[0472] <Example G2-1> A 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Opto Science Co., Ltd.) with an ITO film formed by sputtering to a thickness of 200 nm and polished to 50 nm was used as a transparent support substrate. This transparent support substrate was fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and molybdenum vapor deposition boats containing HATCN, TBB, TcTa, CBP, Compound (1-2), and TPBi, and tungsten vapor deposition boats containing LiF and aluminum were mounted.

[0473] The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was set to 5×10 -4The pressure was reduced to Pa. First, HATCN was heated and vapor-deposited to a thickness of 5 nm to form a hole injection layer. Next, TBB was heated and vapor-deposited to a thickness of 65 nm, and further TcTa was heated and vapor-deposited to a thickness of 10 nm to form a two-layer hole transport layer. Next, CBP and compound (1-2) were simultaneously heated and vapor-deposited to a thickness of 30 nm to form a light-emitting layer. The deposition rate was adjusted so that the weight ratio of CBP to compound (1-2) was approximately 99 to 1. Next, TPBi was heated and vapor-deposited to a thickness of 50 nm to form an electron transport layer. The deposition rate of each layer was 0.01 - 1 nm / second. Thereafter, LiF was heated and vapor-deposited at a deposition rate of 0.01 - 0.1 nm / second to a thickness of 1 nm, and then aluminum was heated and vapor-deposited to a thickness of 100 nm to form a cathode, obtaining an organic EL element. At this time, the deposition rate of aluminum was adjusted to be 1 - 10 nm / second.

[0474] <Examples G2-2 to G2-6, Comparative Example G2-1, Examples G3-1 to G3-6 and Comparative Example G3-1> The host CBP, the dopant compound (1-2), and the host:dopant mixing ratio of Example G2-1 were changed to each host, each dopant, and each mixing ratio described in Table 3 to fabricate each element.

[0475] The evaluation results of each element are shown in Table 4.

Table 4

[0476] In Examples G2-1 to G2-6 and Examples G3-1 to G3-6, high efficiency and long device lifetime were obtained compared to Comparative Example G2-1 and Comparative Example G3-1.

[0477] <Evaluation of Vapor Deposition Type Organic EL Element> Organic EL elements according to Examples G4-1 to G4-4 and Comparative Example G4-1 were fabricated, and the emission wavelength, full width at half maximum, driving voltage, external quantum efficiency, and LT50 (the time to maintain 50% or more of the luminance during constant current driving. In this case, the initial luminance was 500 cd / m 2 at a current density at 500 cd / m 2 When continuously driven at the current density at 500 cd / m 2 the time to maintain a luminance of 250 cd / m ) were measured.

[0478]

Table 5

[0479] The chemical structures of "T2T", "4CzIPN", "BCC-TPTA", and "Liq" are shown below.

[0480]

Chemical Formula

[0481] <Example G4-1> A 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Opto Science Co., Ltd.) with ITO film formed to a thickness of 200 nm by sputtering and polished to 50 nm was used as a transparent support substrate. This transparent support substrate was fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and molybdenum vapor deposition boats containing HATCN, TBB, TcTa, BCC-TPTA, Compound (1-2), T2T, Liq, and TPBi, and tungsten vapor deposition boats containing LiF and aluminum were mounted respectively.

[0482] The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was set to 5×10 -4The pressure was reduced to Pa, and first, HATCN was heated and vapor-deposited to a thickness of 5 nm to form a hole injection layer. Next, TBB was heated and vapor-deposited to a thickness of 65 nm, and further, TcTa was heated and vapor-deposited to a thickness of 10 nm to form a two-layer hole transport layer. Next, TcTa, BCC-TPTA, and compound (1-2) were simultaneously heated and vapor-deposited to a thickness of 30 nm to form a light-emitting layer. The deposition rate was adjusted so that the weight ratio of CBP, BCC-TPTA, and compound (1-2) was approximately 85:14:1. Next, T2T was heated and vapor-deposited to a thickness of 10 nm, and then, TPBi and Liq were heated and vapor-deposited to a thickness of 40 nm to form a two-layer electron transport layer. The deposition rate was adjusted so that the weight ratio of TPBi and Liq was approximately 70:30. The deposition rate of each layer was 0.01 - 1 nm / second. Thereafter, LiF was heated and vapor-deposited at a deposition rate of 0.01 - 0.1 nm / second to a thickness of 1 nm, and then, aluminum was heated and vapor-deposited to a thickness of 100 nm to form a cathode, obtaining an organic EL element. At this time, the deposition rate of aluminum was adjusted to be 1 - 10 nm / second.

[0483] <Examples G4-2 to G4-4 and Comparative Example G4-1> The assisting dopant BCC-TPTA, the dopant compound (1-2), and the mixing ratio, which are the assisting dopant of Example G4-1, were changed to each assisting dopant, each dopant, and each mixing ratio described in Table 5 to fabricate each element.

[0484] The evaluation results of each element are shown in Table 6.

Table 6

[0485] Examples G4-1 to 4-4 obtained higher efficiency and longer device lifetime compared to Comparative Example G4-1. Devices using an exciplex and an assisting dopant, such as Examples G4-1 and G4-2, are feasible.

[0486] <Evaluation of Coating-Type Organic EL Elements> Next, an organic EL element obtained by coating and forming an organic layer will be described.

[0487] <Synthesis of Polymer Host Compound: SPH-101> SPH-101 was synthesized according to the method described in International Publication No. 2015 / 008851. A copolymer in which M2 or M3 is bonded next to M1 was obtained, and each unit is presumed to be 50:26:24 (molar ratio) from the charging ratio. In the following structural formula, Me is a methyl group, Bpin is a pinacolato boryl group, and * is the connection point of each unit.

Chemical formula

[0488] <Synthesis of Polymer Hole Transport Compound: XLP-101> XLP-101 was synthesized according to the method described in Patent Publication No. 2018-61028. A copolymer in which M5 or M6 is bonded next to M4 was obtained, and each unit is presumed to be 40:10:50 (molar ratio) from the charging ratio. In the following structural formula, Me is a methyl group, Bpin is a pinacolato boryl group, and * is the connection point of each unit.

Chemical formula

[0489] <Examples 2-1 to 2-9> A coating solution of the material for forming each layer was prepared to fabricate a coating-type organic EL element.

[0490] <Fabrication of Organic EL Elements of Examples 2-1 to 2-3> The material compositions of each layer in the organic EL element are shown in Table 7.

Table 7

[0491] The structure of "ET1" in Table 4 is shown below.

Chemical formula

[0492] <Preparation of Composition (1) for Forming Light-Emitting Layer> The composition (1) for forming a light-emitting layer is prepared by stirring the following components until a homogeneous solution is obtained. The prepared composition for forming a light-emitting layer is spin-coated on a glass substrate and dried by heating under reduced pressure to obtain a coating film without film defects and excellent in smoothness. Compound (A) 0.04 wt% SPH-101 1.96 wt% Xylene 69.00 wt% Decalin 29.00 wt%

[0493] Compound (A) is a polycyclic aromatic compound represented by the general formula (1A-1) (for example, Compound (1-2)), a polymer compound obtained by polymerizing the polycyclic aromatic compound as a monomer (i.e., the monomer has a reactive substituent), or a polymer cross-linked product obtained by further cross-linking the polymer compound. The polymer compound for obtaining the polymer cross-linked product has a cross-linkable substituent.

[0494] <PEDOT:PSS Solution> A commercially available PEDOT:PSS solution (Clevios(TM) P VP AI4083, an aqueous dispersion of PEDOT:PSS, manufactured by Heraeus Holdings) is used.

Chemical formula

[0495] <Preparation of OTPD Solution> OTPD (LT-N159, manufactured by Luminescence Technology Corp) and IK-2 (a photo cationic polymerization initiator, manufactured by San-Apro) are dissolved in toluene to prepare an OTPD solution with an OTPD concentration of 0.7 wt% and an IK-2 concentration of 0.007 wt%.

Chemical formula

[0496] <Preparation of XLP-101 Solution> Dissolve XLP-101 in xylene at a concentration of 0.6% by weight to prepare a 0.6% by weight XLP-101 solution.

[0497] <Preparation of PCz Solution> Dissolve PCz (polyvinylcarbazole) in dichlorobenzene to prepare a 0.7% by weight PCz solution. [Chemical formula]

[0498] <Example 2-1> On a glass substrate with ITO deposited to a thickness of 150 nm, spin-coat the PEDOT:PSS solution and bake it on a hot plate at 200 °C for 1 hour to form a PEDOT:PSS film with a thickness of 40 nm (hole injection layer). Then, spin-coat the OTPD solution, dry it on a hot plate at 80 °C for 10 minutes, and then expose it with an exposure intensity of 100 mJ / cm 2 and bake it on a hot plate at 100 °C for 1 hour to form an OTPD film with a thickness of 30 nm that is insoluble in the solution (hole transport layer). Then, spin-coat the composition (1) for forming the light-emitting layer and bake it on a hot plate at 120 °C for 1 hour to form a light-emitting layer with a thickness of 20 nm.

[0499] Fix the fabricated multilayer film to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and attach a molybdenum vapor deposition boat containing ET1, a molybdenum vapor deposition boat containing LiF, and a tungsten vapor deposition boat containing aluminum. After evacuating the vacuum chamber to 5×10 -4 Pa, heat ET1 and deposit it to a thickness of 30 nm to form an electron transport layer. The deposition rate when forming the electron transport layer shall be 1 nm / second. Then, heat LiF and deposit it at a deposition rate of 0.01 - 0.1 nm / second to a thickness of 1 nm. Next, heat aluminum and deposit it to a thickness of 100 nm to form the cathode. In this way, an organic EL element is obtained.

[0500] <Example 2-2> An organic EL element is obtained in the same manner as in Example 2-1. For the hole transport layer, an XLP-101 solution is spin-coated and baked on a hot plate at 200 °C for 1 hour to form a film with a thickness of 30 nm.

[0501] <Example 2-3> An organic EL element is obtained in the same manner as in Example 2-1. For the hole transport layer, a PCz solution is spin-coated and baked on a hot plate at 120 °C for 1 hour to form a film with a thickness of 30 nm.

[0502] <Evaluation of the Organic EL Elements of Examples 2-1 to 2-3> It can be expected that the coating-type organic EL element obtained as described above also has excellent driving voltage and external quantum efficiency similar to those of the vapor deposition-type organic EL element.

[0503] <Fabrication of the Organic EL Elements of Examples 2-4 to 2-6> The material compositions of each layer in the organic EL element are shown in Table 8.

Table 8

[0504] <Preparation of the Luminescent Layer-Forming Compositions (2) to (4)> The luminescent layer-forming composition (2) is prepared by stirring the following components until a homogeneous solution is obtained. Compound (A) 0.02 wt% mCBP 1.98 wt% Toluene 98.00 wt%

[0505] The luminescent layer-forming composition (3) is prepared by stirring the following components until a homogeneous solution is obtained. Compound (A) 0.02 wt% SPH-101 1.98 wt% Xylene 98.00 wt%

[0506] The light-emitting layer forming composition (4) is prepared by stirring the following components until a uniform solution is obtained. Compound (A) 0.02 wt% DOBNA 1.98 wt% Toluene 98.00 wt%

[0507] In Table 5, "mCBP" is 3,3'-bis(N-carbazolyl)-1,1'-biphenyl, "DOBNA" is 3,11-di-o-tolyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene, and "TSPO1" is diphenyl[4-(triphenylsilyl)phenyl]phosphine oxide. The chemical structures are shown below.

Chemical formula

[0508] <Example 2-4> On a glass substrate on which ITO is formed to a thickness of 45 nm, an ND-3202 (manufactured by Nissan Chemical Industries, Ltd.) solution is spin-coated, and then heated at 50°C for 3 minutes and further at 230°C for 15 minutes in an air atmosphere to form an ND-3202 film with a thickness of 50 nm (hole injection layer). Next, an XLP-101 solution is spin-coated and heated on a hot plate at 200°C for 30 minutes in a nitrogen gas atmosphere to form an XLP-101 film with a thickness of 20 nm (hole transport layer). Next, the light-emitting layer forming composition (2) is spin-coated and heated at 130°C for 10 minutes in a nitrogen gas atmosphere to form a 20-nm light-emitting layer.

[0509] The fabricated multilayer film is fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing TSPO1, a molybdenum vapor deposition boat containing LiF, and a tungsten vapor deposition boat containing aluminum are attached. The vacuum chamber is 5×10 -4After reducing the pressure to Pa, heat TSPO1 and deposit it at a deposition rate of 1 nm / second to form an electron transport layer with a film thickness of 30 nm. Then, heat LiF and deposit it at a deposition rate of 0.01 - 0.1 nm / second to a film thickness of 1 nm. Next, heat aluminum and deposit it to a film thickness of 100 nm to form a cathode. In this way, an organic EL element is obtained.

[0510] <Example 2-5 and Example 2-6> Using the composition (3) or (4) for forming the light-emitting layer, an organic EL element is obtained in the same manner as in Example 2-4.

[0511] <Evaluation of the organic EL elements of Example 2-4 to Example 2-6> It can be expected that the coating-type organic EL element obtained as described above also has excellent driving voltage and external quantum efficiency similar to those of the vapor deposition-type organic EL element.

[0512] <Fabrication of the organic EL elements of Example 2-7 to Example 2-9> The material composition of each layer in the organic EL element is shown in a table.

Table 9

[0513] <Preparation of the composition (5) - (7) for forming the light-emitting layer> The composition (5) for forming the light-emitting layer is prepared by stirring the following components until a uniform solution is obtained. Compound (A) 0.02 wt% 2PXZ-TAZ 0.18 wt% mCBP 1.80 wt% Toluene 98.00 wt%

[0514] The composition (6) for forming the light-emitting layer is prepared by stirring the following components until a uniform solution is obtained. Compound (A) 0.02 wt% 2PXZ-TAZ 0.18 wt% SPH-101 1.80 wt% Xylene 98.00 wt%

[0515] The luminescent layer forming composition (7) is prepared by stirring the following components until a uniform solution is obtained. Compound (A) 0.02 wt% 2PXZ-TAZ 0.18 wt% DOBNA 1.80 wt% Toluene 98.00 wt%

[0516] In Table 9, "2PXZ-TAZ" is 10,10'-((4-phenyl-4H-1,2,4-triazole-3,5-diyl)bis(4,1-phenylene))bis(10H-phenoxazine). The chemical structure is shown below.

Chemical formula

[0517] <Example 2-7> On a glass substrate on which ITO was formed to a thickness of 45 nm, a solution of ND-3202 (manufactured by Nissan Chemical Industries, Ltd.) was spin-coated, and then heated at 50°C for 3 minutes and further heated at 230°C for 15 minutes in an air atmosphere to form an ND-3202 film with a thickness of 50 nm (hole injection layer). Next, an XLP-101 solution was spin-coated and heated on a hot plate at 200°C for 30 minutes in a nitrogen gas atmosphere to form an XLP-101 film with a thickness of 20 nm (hole transport layer). Next, the luminescent layer forming composition (5) was spin-coated and heated at 130°C for 10 minutes in a nitrogen gas atmosphere to form a 20-nm-thick luminescent layer.

[0518] The fabricated multilayer film was fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing TSPO1, a molybdenum vapor deposition boat containing LiF, and a tungsten vapor deposition boat containing aluminum were attached. The vacuum chamber was evacuated to 5×10 -4After reducing the pressure to Pa, TSPO1 is heated and vapor-deposited to a film thickness of 30 nm to form an electron transport layer. The vapor deposition rate when forming the electron transport layer is set to 1 nm / second. Then, LiF is heated and vapor-deposited at a vapor deposition rate of 0.01 to 0.1 nm / second to a film thickness of 1 nm. Next, aluminum is heated and vapor-deposited to a film thickness of 100 nm to form a cathode. In this way, an organic EL element is obtained.

[0519] <Example 2-8 and Example 2-9> Using the composition (6) or (7) for forming the light-emitting layer, an organic EL element is obtained in the same manner as in Example 2-7.

[0520] <Evaluation of the organic EL elements of Example 2-7 to Example 2-9> It can be predicted that the coating-type organic EL element obtained as described above also has excellent driving voltage and external quantum efficiency similar to those of the vapor deposition-type organic EL element.

[0521] As described above, some of the compounds according to the present invention were evaluated as materials for organic EL elements, and it was shown that they are excellent materials. However, other compounds that have not been evaluated also have the same basic skeleton and overall similar structures. Those skilled in the art can understand that they are also excellent materials for organic EL elements.

Explanation of symbols

[0522] 100 Organic electroluminescent element 101 Substrate 102 Anode 103 Hole injection layer 104 Hole transport layer 105 Light-emitting layer 106 Electron transport layer 107 Electron injection layer 108 Cathode

Claims

1. A polycyclic aromatic compound represented by formula (1A-1), or a polycyclic aromatic compound which is a dimer in which two structural units represented by formula (1A-1) are bonded so as to share the A1 ring, A2 ring, A3 ring, A4 ring, or A5 ring with a plurality of unit structures. 【Chemical Formula 1】 In formula (1A-1), The A2 ring, A3 ring, and A4 ring are each independently a substituted or unsubstituted benzene ring, The A1 ring and A5 ring are each independently a substituted or unsubstituted benzene ring; Y1 is B; L1 and L2 are each orthophenylene, and L3 and L4 are each a single bond; n, m, q, and r are each independently 0 or 1, and in the case of 0, it means that the carbon atom bonded to L1, L2, L3, or L4 is substituted with hydrogen or a substituent, provided that n + m = 1 and q + r = 1; The polycyclic aromatic compound represented by formula (1A-1) and the polycyclic aromatic compound which is the dimer are each either not condensed with at least one cycloalkane or are condensed, and at least one hydrogen in the cycloalkane is either not substituted or is substituted, and at least one —CH 2 — in the cycloalkane is either not substituted with —O— or —S— or is substituted, and; At least one hydrogen in each of the polycyclic aromatic compound represented by formula (1A-1) and the polycyclic aromatic compound which is the dimer is either not substituted or is substituted with cyano, halogen, or deuterium.

2. The polycyclic aromatic compound according to Claim 1, represented by the following formula (1c-1), formula (1c-2), formula (1c-3), or formula (1c-4). 【Chemical Formula 2】 (In formula (1c-1), formula (1c-2), formula (1c-3), and formula (1c-4), Z is independently C-R1 each, and said C-R 1 wherein R 1 is independently hydrogen, aryl, heteroaryl, diarylamino, diheteroaryl amino, arylheteroaryl amino, diarylboril, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these is unsubstituted or substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl; The polycyclic aromatic compound represented by formula (1c-1), formula (1c-2), formula (1c-3), or formula (1c-4) is not condensed or condensed with at least one cycloalkane, and at least one hydrogen in the cycloalkane is unsubstituted or substituted, and at least one -CH 2 - is unsubstituted or substituted by -O- or -S-, and; At least one hydrogen in the polycyclic aromatic compound represented by formula (1c-1), formula (1c-2), formula (1c-3), or formula (1c-4) is unsubstituted or substituted by cyano, halogen, or deuterium. )

3. The polycyclic aromatic compound according to claim 2, represented by any of the following structural formulas. 【Chemical formula 3】 (In the above formula, tBu is t-butyl.)

4. The polycyclic aromatic compound according to claim 1, represented by any of formula (1c-d-1), formula (1c-d-2), formula (1c-d-3), formula (1c-d-4), formula (1c-d-5), formula (1c-d-6), formula (1c-d-7), formula (1c-d-8), formula (1c-d-9), formula (1c-d-10), formula (1c-d-11), formula (1c-d-12), formula (1c-d-13), formula (1c-d-14), formula (1c-d-15), formula (1c-d-16), formula (1c-d-17), formula (1c-d-18), or formula (1c-d-19). 【Chemical 4】 【Chemical 5】 【Chemical 6】 【Chemical 7】 (In the above formulas, Z is, independently of each other, C—R1, Each R1 is independently hydrogen, aryl, heteroaryl, diarylamino, diheteroarylamino, arylheteroarylamino, diarylboryl, alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these is unsubstituted or substituted by aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl.)

5. The polycyclic aromatic compound according to claim 4, which is represented by any of the following structural formulas. 【Chemical 8】

6. A material for an organic device, containing the polycyclic aromatic compound according to any one of claims 1 to 5.

7. An organic electroluminescent device including a pair of electrodes composed of an anode and a cathode, and a light-emitting layer disposed between the pair of electrodes, wherein the light-emitting layer contains the polycyclic aromatic compound according to any one of claims 1 to 5.

8. The organic electroluminescent device according to claim 7, wherein the light-emitting layer contains a host and the polycyclic aromatic compound as a dopant.

9. A display device or a lighting device including the organic electroluminescent device according to any one of claims 7 or 8.

Images