Polycyclic aromatic compound

Abstract

To provide a novel compound suitable as a material for organic devices such as an organic EL device.SOLUTION: The present invention discloses a polycyclic aromatic compound having a structure comprising one or more structural units represented by formula (1) [where, A ring, B ring and C ring each denote a substituted / unsubstituted aryl ring or a substituted / unsubstituted heteroaryl ring; Y1 is B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R; X1 and X2 each denote >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, where at least one of X1 and X2 is >N-R with R being a group represented by formula (G)].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 elements 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, regarding 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, active research has been conducted so far regardless of whether they are high-molecular compounds or low-molecular compounds.

[0003] An organic electroluminescent device has a structure including a pair of electrodes composed of 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. Various suitable 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. An organic electroluminescent device containing this polycyclic aromatic compound has been reported to have good external quantum efficiency. Patent Documents 2 and 3 disclose polycyclic aromatic compounds having a condensed cycloalkane structure. Due to this condensed cycloalkane structure, it has a low sublimation temperature and high stability, and thus has the effect of obtaining an organic electroluminescent device having excellent efficiency and long-life characteristics, and the effect of suppressing concentration quenching due to the condensed cycloalkyl structure can also be expected.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 International Publication No. 2015 / 102118 Patent Document 2 International Publication No. 2020 / 017931 Patent Document 3 International Publication No. 2020 / 218079 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 inventors of the present invention have intensively studied to solve the above problems, and have succeeded in producing a novel polycyclic aromatic compound having more excellent light-emitting characteristics among polycyclic aromatic compounds having a structure similar to the compound described in Patent Document 1. That is, by combining a condensed cycloalkyl structure having an effect of suppressing concentration quenching and a specific substitution structure, a polycyclic aromatic compound having high luminous efficiency and the like was successfully produced. Further, by arranging a layer containing this polycyclic aromatic compound between a pair of electrodes to form an organic EL element, it was found that an excellent organic EL element can be obtained, and the present invention was completed. That is, the present invention provides a polycyclic aromatic compound as described below, and further an organic device material containing the polycyclic aromatic compound as described below.

[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 (1); [Chemical formula] In formula (1), Ring A, Ring B, and Ring C are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring; Y 1 is B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R, wherein R of the Si-R and the Ge-R is a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl, or a substituted or unsubstituted cycloalkyl; X 1 and X 2 are >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, wherein R of the >N-R is hydrogen, a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl, or a substituted or unsubstituted cycloalkyl, or a monovalent group represented by formula (G), and R of the >C(-R)2 and the >Si(-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 two Rs of the >C(-R)2 and the >Si(-R)2 may be bonded to each other to form a ring, and at least one of R of the >N-R, the >C(-R)2, and the >Si(-R)2 may be bonded to at least one of Ring A and Ring B or at least one of Ring A and Ring C via a single bond or a linking group, provided that at least one of X 1 and X 2 is >N-R where R is a monovalent group represented by formula (G), In formula (G), L is a single bond, alkylene, cycloalkylene, arylene or heteroarylene, at least one hydrogen of these may be substituted, and (G-A) ring and (G-B) ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring; X 3 and X4 Each is independently >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, and R of said >N-R, said >C(-R)2, and said >Si(-R)2 are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl. Two Rs of said >C(-R)2 and said >Si(-R)2 may be bonded to each other to form a ring. At least one R of said >N-R, said >C(-R)2 and said >Si(-R)2 may be bonded to at least one of said (G-A) ring and said (G-B) ring, or at least one of said (G-A) ring and said (G-B) ring via a single bond or a linking group. In the structure represented by formula (1), at least one of the aryl ring or heteroaryl ring may be condensed with at least one cycloalkane. At least one hydrogen in the cycloalkane may be substituted. At least one -CH2- in the cycloalkane may be substituted with -O-. And; At least one hydrogen in the structure represented by formula (1) may be substituted with cyano, halogen, or deuterium. <2> The polycyclic aromatic compound according to <1>, wherein the structural unit represented by formula (1) is the structural unit represented by the following formula (2);

Chemical formula

Chemical formula

Advantages of the Invention

[0010] The present invention provides a novel polycyclic aromatic compound useful as a material for organic devices such as organic electroluminescent elements. The polycyclic aromatic compound of the present invention can be used in the manufacture of organic devices such as organic electroluminescent elements.

Brief Description of Drawings

[0011]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on typical embodiments or specific examples, but the present invention is not limited to such embodiments. In this specification, the 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 the description of the structural formula in this specification, "hydrogen" means "hydrogen atom (H)". In this specification, an organic electroluminescent element may be referred to as an organic EL element.

[0013] In this specification, chemical structures and substituents 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, the number of carbon atoms refers to 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.

[0014] Since the chemical structural formulas described in this specification (including general formulas drawn in Markush structural formulas as in formula (1) described later) are planar structural formulas, in reality, there may exist various isomeric structures such as enantiomers, diastereoisomers, and rotational isomers. In this specification, unless otherwise specified, the described compounds may be any isomeric structures conceivable from their planar structural formulas, or may be mixtures of any ratios composed of possible isomers.

[0015] <1. 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 (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.

[0016]

Chemical Structure

[0017] In formula (1), ring A, ring B, and ring C are each independently an optionally substituted aryl ring or an optionally substituted heteroaryl ring.

[0018] The aryl ring or heteroaryl ring in Ring A, Ring B, and Ring C is Y 1 as well as X 1 and X 2 is preferably bonded to either one of them and a 5-membered ring or 6-membered ring. "Y 1 as well as X 1 and X 2 is bonded to either one of them and a 5-membered ring or 6-membered ring" means that the ring is formed only by this 5-membered ring or 6-membered ring, or that other rings are further condensed to form a ring including this 5-membered ring or 6-membered ring. In other words, it means that the 5-membered ring or 6-membered ring that constitutes all or part of the ring is bonded to either one of Y 1 as well as X 1 and X 2 In the aryl ring or heteroaryl ring in Ring A, Ring B, and Ring C, two or three consecutive ring-constituting atoms (carbon atoms) may be directly bonded to either one of Y 1 as well as X 1 and X 2 That is, in the aryl ring or heteroaryl ring in Ring B, any two consecutive ring-constituting atoms (carbon atoms) are directly bonded to Y 1 as well as X 1 and in the aryl ring or heteroaryl ring in Ring C, any two consecutive ring-constituting atoms (carbon atoms) are directly bonded to Y 1 as well as X 2 and in the aryl ring or heteroaryl ring in Ring A, any three consecutive ring-constituting atoms (carbon atoms) are directly bonded to Y 1 , X 1 and X 2

[0019] Examples of the "aryl ring" in Ring A, Ring B, or Ring C of formula (1) include aryl rings having 6 to 30 carbon atoms, preferably aryl rings having 6 to 16 carbon atoms, more preferably aryl rings having 6 to 12 carbon atoms, and particularly preferably aryl rings having 6 to 10 carbon atoms.

[0020] ​Specific "aryl rings" 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. Further, the fluorene ring, benzofluorene ring, and indene ring each include a structure in which a fluorene ring, benzofluorene ring, cyclopentane ring, etc. are spiro-bonded. In addition, for the fluorene ring, benzofluorene ring, and indene ring, those in which two of the two hydrogens of methylene are each substituted with an alkyl such as methyl as the first substituent described later, such as a dimethylfluorene ring, a dimethylbenzofluorene ring, and a dimethylindene ring, are also included.

[0021] Examples of the "heteroaryl ring" in the A ring, B ring, or C ring of formula (1) include, for example, a heteroaryl ring having 2 to 30 carbon atoms, preferably a heteroaryl ring having 2 to 25 carbon atoms, more preferably a heteroaryl ring having 2 to 20 carbon atoms, still more preferably a heteroaryl ring having 2 to 15 carbon atoms, and particularly preferably a heteroaryl ring having 2 to 10 carbon atoms. Further, examples of the "heteroaryl ring" include a heterocyclic ring containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen in addition to carbon as ring-constituting atoms.

[0022] 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. Also, dihydroacridine ring, xanthene ring, thioxanthene ring, in which two of the two hydrogens of methylene are each substituted with an alkyl such as methyl as the first substituent described below to form a dimethyldihydroacridine ring, dimethylxanthene ring, dimethylthioxanthene ring, etc., are also preferred. Also, bipyridine ring, phenylpyridine ring, pyridylphenyl ring which are bicyclic systems, and terpyridyl ring, bispyridylphenyl ring, pyridylbiphenyl ring which are tricyclic systems are also mentioned as "heteroaryl rings". Also, the "heteroaryl ring" shall include a pyran ring.

[0023] Also, the following formula (BO) is also included in the heteroaryl ring.

Chemical formula

[0024] At least one hydrogen in the above-mentioned "aryl ring" or "heteroaryl ring" may be substituted with a first substituent, which is a substituted or unsubstituted "aryl", a substituted or unsubstituted "heteroaryl", a substituted or unsubstituted "diaryl amino (the two aryls may not be bonded to each other or may be bonded via a linking group)", a substituted or unsubstituted "diheteroaryl amino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group)", a substituted or unsubstituted "aryl heteroaryl amino (the aryl and the heteroaryl may not be bonded to each other or may be bonded via a linking group)", a substituted or unsubstituted "diaryl boryl (the two aryls may not be bonded to each other or may be bonded via a single bond or a linking group)", 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".

[0025] Specifically, "aryl" is a monovalent group obtained by removing one hydrogen from the above-mentioned "aryl ring". For example, aryl having 6 to 30 carbon atoms can be mentioned, aryl having 6 to 24 carbon atoms is preferable, aryl having 6 to 20 carbon atoms is more preferable, aryl having 6 to 16 carbon atoms is further preferable, aryl having 6 to 12 carbon atoms is particularly preferable, and aryl having 6 to 10 carbon atoms is most preferable.

[0026] In addition, "heteroaryl" is a monovalent group obtained by removing one hydrogen from the above-mentioned "heteroaryl ring". For example, heteroaryl having 2 to 30 carbon atoms can be mentioned, heteroaryl having 2 to 25 carbon atoms is preferable, heteroaryl having 2 to 20 carbon atoms is more preferable, heteroaryl having 2 to 15 carbon atoms is further preferable, and heteroaryl having 2 to 10 carbon atoms is particularly preferable. In addition, examples of heteroaryl include heterocycles containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen in addition to carbon as ring-constituting atoms.

[0027] As the first substituent, for each of "optionally substituted diarylamino (the two aryls may or may not be connected via a linking group)", "optionally substituted diheteroarylamino (the two heteroaryls may or may not be connected via a linking group)", and "optionally substituted arylheteroarylamino (the aryl and the heteroaryl may or may not be connected via a linking group)", the aryl or heteroaryl described above for "aryl" and "heteroaryl" can be cited.

[0028] The description "may or may not be connected via a linking group" in diarylamino (the two aryls may or may not be connected via a linking group) as the first substituent, diheteroarylamino (the two heteroaryls may or may not be connected via a linking group) as the first substituent, and arylheteroarylamino (the aryl and the heteroaryl may or may not be connected via a linking group) as the first substituent 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.

[0029]

Chemical formula

[0030] 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, where R X is independently alkyl, cycloalkyl, aryl or heteroaryl, which may be substituted with alkyl, cycloalkyl, aryl or heteroaryl, and >C(-RX ) 2. >Si(-R X ) 2, the R in X may be a single bond or a linking group X Y and may form a ring by bonding through. X Y Examples of X include >O, >N-R Y , >C(-R Y ) 2, >Si(-R Y ) 2, >S, >CO, >CS, >SO, >SO2, and >Se. Each R Y is independently alkyl, cycloalkyl, aryl or heteroaryl, and these may be substituted with alkyl, cycloalkyl, aryl or heteroaryl. However, when X Y is >C(-R Y ) 2 and >Si(-R Y ) 2, the two Rs Y do not combine to form an additional ring. Further, examples of the linking group include alkenylene. Any hydrogen of the alkenylene may be independently substituted with R X , and each R X is independently alkyl, cycloalkyl, substituted silyl, aryl and heteroaryl, and these may be substituted with alkyl, cycloalkyl, substituted silyl, aryl.

[0031] In addition, when simply described as "diaryl amino", "diheteroaryl amino" or "aryl heteroaryl amino" in this specification, unless otherwise specified, each means "the two aryls may or may not be bonded through a linking group", "the two heteroaryls may or may not be bonded through a linking group", and "the aryl and heteroaryl may or may not be bonded through a linking group", respectively.

[0032] The "alkyl" as the first substituent may be either linear or branched, and examples thereof include 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 8 carbon atoms (branched alkyl having 3 to 8 carbon atoms) is even more preferred, alkyl having 1 to 6 carbon atoms (branched alkyl having 3 to 6 carbon atoms) is particularly preferred, and alkyl having 1 to 5 carbon atoms (branched alkyl having 3 to 5 carbon atoms) is most preferred.

[0033] Specific alkyls include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl (t-amyl), n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, t-octyl (1,1,3,3-tetramethylbutyl), 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, 3,5,5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-eicosyl, etc. Further, 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, etc. can also be mentioned.

[0034] 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 photoluminescence quantum yield (PLQY). In addition, a substituent in which the tertiary-alkyl represented by the formula (tR) is substituted for another substituent as the second substituent is also preferred. Specifically, diarylamino substituted with tertiary-alkyl represented by (tR) (the two aryls may not be bonded to each other or may be bonded via a linking group), 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. For "diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group)", the groups described as the following "first substituent" can be mentioned. As the substitution form of the group of formula (tR) for diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), carbazolyl, and benzocarbazolyl, an example in which some or all of the hydrogens of the aryl ring or benzene ring in these groups are substituted with the group of formula (tR) can be given.

[0035] [Chemical formula]

[0036] In formula (tR), R a , R b , and R c are each independently alkyl having 1 to 24 carbon atoms, and any -CH2- in the alkyl may be substituted with -O-, and the group represented by formula (tR) substitutes at least one hydrogen in the structure containing the structural unit represented by formula (1) at *.

[0037] 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).

[0038] R in the formula (tR) of the formula (1) a , R b , and R c The total number of carbon atoms of, and is preferably 3 to 20 carbon atoms, particularly preferably 3 to 10 carbon atoms.

[0039] R a , R b , and R c Specific examples of the alkyl group of, and 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.

[0040] 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.

[0041] 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.

[0042] Specific examples of cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, 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 C1-C5 alkyl (especially methyl) substituents thereof.

[0043] Examples of the "alkenyl" as the first substituent include 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 the "alkenyl" include vinyl, allyl, butadienyl, and the like.

[0044] 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 still more preferred, and alkoxy having 1 to 5 carbon atoms (branched alkoxy having 3 to 5 carbon atoms) is particularly preferred.

[0045] Specific examples of the alkoxy include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, t-amyloxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, and the like.

[0046] The "arylthio" as the first substituent is a group in which the hydrogen of the -SH group is substituted with an aryl, and the aryl described above can be cited.

[0047] 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.

[0048] Examples of "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 alkyls for substitution are alkyls having 1 to 5 carbon atoms, and specifically include methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl, t-amyl, etc.

[0049] Specific examples of trialkylsilyl 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, etc.

[0050] Examples of "tricycloalkylsilyl" include groups in which the three hydrogens in the silyl group are each independently substituted with a cycloalkyl group, and this cycloalkyl group can refer to the groups described as "cycloalkyl" in the above-mentioned first substituent. 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.

[0051] Specific examples of tricycloalkylsilyl include tricyclopentylsilyl, tricyclohexylsilyl, and the like.

[0052] Specific examples of dialkylcycloalkylsilyl substituted with two alkyl groups and one cycloalkyl group, and alkyldicycloalkylsilyl substituted with one alkyl group and two cycloalkyl groups include silyl groups substituted with groups selected from the above-mentioned specific alkyl and cycloalkyl groups.

[0053] Specific examples of dialkylarylsilyl substituted with two alkyl groups and one aryl group, alkyldiarylsilyl substituted with one alkyl group and two aryl groups, and triarylsilyl substituted with three aryl groups include silyl groups substituted with groups selected from the above-mentioned specific alkyl and aryl groups. Specific examples of triarylsilyl include, in particular, triphenylsilyl.

[0054] In addition, as the "aryl" in the "diarylboronyl (the two aryls are not bonded to each other or are bonded via a single bond or a linking group)" 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 (e.g., >C(-R)2, >O, >S or >N-R). Here, R in >C(-R)2 and >N-R is aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or may be bonded via a linking group), alkyl, cycloalkyl, alkoxy or aryloxy (the above are the first substituents), and the first substituent may be further substituted with aryl, heteroaryl, alkyl or cycloalkyl (the above are the second substituents). Specific examples of these groups can cite the descriptions of aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or may be bonded via a linking group), alkyl, cycloalkyl, alkoxy, or aryloxy as the first substituents mentioned above.

[0055] The first substituent, which is a substituted or unsubstituted "aryl", a substituted or unsubstituted "heteroaryl", a substituted or unsubstituted "diaryl amino (the two aryls are not bonded to each other or are bonded via a linking group)", a substituted or unsubstituted "diheteroaryl amino (the two heteroaryls are not bonded to each other or are bonded via a single bond or a linking group)", a substituted or unsubstituted "aryl heteroaryl amino (the aryl and the heteroaryl are not bonded to each other or are bonded via a single bond or a linking group)", a substituted or unsubstituted "diaryl boryl (the two aryls are not bonded to each other or are bonded via a single bond or a linking group)", 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", as described as being substituted or unsubstituted, at least one hydrogen in them may be substituted with a second substituent. As this second substituent, preferably, aryl, heteroaryl, diaryl amino, alkyl, cycloalkyl, or substituted silyl can be mentioned, and specific examples thereof can refer to the descriptions of "aryl", "heteroaryl", "diaryl amino", "alkyl", "cycloalkyl", or "substituted silyl" as the first substituent. Also, for aryl or 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 or 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. This description can also be applied to the descriptions of other first substituents and second substituents in this specification.

[0056] 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.

[0057] 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

[0058]

Chemical formula

[0059]

Chemical formula

[0060]

Chem.

[0061]

Chem.

[0062]

Chem.

[0063]

Chem.

[0064]

Chem.

[0065]

Chem.

[0066]

Chem.

[0067]

Chem.

[0068] [Chemical formula]

[0069] The polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) preferably has a structure containing at least one of the tertiary-alkyl (such as t-butyl or t-amyl), neopentyl or adamantyl represented by the above formula (tR), and preferably contains the tertiary-alkyl (such as t-butyl or t-amyl) represented by formula (tR). This is because such bulky substituents increase the intermolecular distance, thereby improving the luminescence quantum yield (PLQY). Further, as the substituent, diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group) is also preferable. Furthermore, diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group) substituted with the group of formula (tR), carbazolyl (preferably, N-carbazolyl) substituted with the group of formula (tR) or benzocarbazolyl (preferably, N-benzocarbazolyl) substituted with the group of formula (tR) are also preferable. Examples of the substitution form of the group of formula (tR) for diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), 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 formula (tR).

[0070] In formula (1), Y 1 is independently B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R, B or P=O is preferable, and B is most preferable. R in the Si-R and Ge-R is aryl having 6 to 12 carbon atoms, alkyl having 1 to 6 carbon atoms, or cycloalkyl having 3 to 14 carbon atoms. Y in formula (1) 1In Si-R and Ge-R, R is aryl, alkyl or cycloalkyl, and examples of such aryl, alkyl or cycloalkyl include the groups described above. Particularly preferred are aryl having 6 to 10 carbon atoms (e.g., phenyl, naphthyl, etc.), alkyl having 1 to 5 carbon atoms (e.g., methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl).

[0071] X in formula (1) 1 and X 2 are each independently >O, >N-R, >Si(-R)2, >C(-R)2, >S, >Se, or >N-R where R is a monovalent group represented by formula (G). In formula (2) described later, including the case where >N-R where R is a monovalent group represented by formula (G-2), such a form of >N-R is represented as >N-G in this specification. However, at least one of X 1 and X 2 is >N-G. When one of X 1 and X 2 is >N-G, the other X 1 or X 2 is preferably >N-G, >N-R, >C(-R)2, or >O, and more preferably >N-G or >N-R.

[0072] X 1 or X 2 In >N-R where R is hydrogen, optionally substituted aryl (except amino as a substituent), optionally substituted heteroaryl, optionally substituted alkyl or optionally substituted cycloalkyl. R in >Si(-R)2 where X 1 and X 2 are each independently hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkyl or optionally substituted cycloalkyl.

[0073] X 1 or X 2>Si(-R)2 and >C(-R)2, where R is, independently of one another, hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkyl, or optionally substituted cycloalkyl, and preferably the two Rs are identical, and the two Rs may be joined to form a ring.

[0074] X 1 or X 2 For aryl, heteroaryl, alkyl, and cycloalkyl in R of >N-R, >Si(-R)2, or >C(-R)2, reference may be made to their descriptions as the above first substituents.

[0075] X 1 or X 2 R of >N-R is preferably optionally substituted aryl, optionally substituted heteroaryl, or optionally substituted cycloalkyl, more preferably optionally substituted aryl or optionally substituted heteroaryl. Examples of cycloalkyl are given below. Here, as aryl, phenyl, biphenylyl (especially 2-biphenylyl), and terphenyl (especially terphenyl-2'-yl) are preferred, and as heteroaryl, benzothienyl (2-benzothienyl, 6-benzothienyl, etc.), benzofuranyl (2-benzofuranyl, 3-benzofuranyl, 5-benzofuranyl, etc.), dibenzofuranyl (2-dibenzofuranyl, 3-dibenzofuranyl, 4-dibenzofuranyl, 5-dibenzofuranyl, etc.) are preferred. As the substituent, tertiary-alkyl represented by the above formula (tR) (especially t-butyl) or cycloalkyl (especially adamantyl) is preferred. The number of substituents in aryl and heteroaryl is preferably 0 to 2, more preferably 1 or 2, and even more preferably 1. It is also preferred when the aryl ring in the above aryl is condensed with an optionally substituted cycloalkane as described below. Specific cycloalkanes can be referred to those described below.

[0076] X1 or X 2 As particularly preferred examples of R in >N-R which is > or X, there may be mentioned optionally substituted 2-biphenylyl, optionally substituted terphenyl-2'-yl, and aryl (optionally substituted) condensed with cycloalkane. As the optionally substituted 2-biphenylyl, 2-biphenylyl substituted with 1 to 3 t-butyl groups is particularly preferred. As the optionally substituted terphenyl-2'-yl, unsubstituted [1,1':3',1''-terphenyl]-2'-yl is particularly preferred. As the aryl condensed with cycloalkane, the following are particularly preferred.

[0077] [Chemical formula] (Me is methyl, tBu is t-butyl, * indicates the bonding position.)

[0078] X 1 and X 2 When either one of and X is >N-R, it is also preferable that R in >N-R is aryl (optionally substituted) condensed with cycloalkane.

[0079] X 1 or X 2 In at least one of >N-R, >Si(-R)2 and >C(-R)2 which is > or X, R may be bonded to either one of ring A and ring B, or either one of ring A and ring C by a linking group or a single bond. That is, in at least one of >N-R, >Si(-R)2 and >C(-R)2 which is > 1 X, R may be bonded to either one of ring A and ring B by a linking group or a single bond, and in at least one of >N-R, >Si(-R)2 and >C(-R)2 which is > 2 X, R may be bonded to either one of ring A and ring C by a linking group or a single bond. As the linking group, -O-, -S-, or -C(-R 13 )2- is preferable. The R in the said "-C(-R 13 )2-" 13is hydrogen, alkyl or cycloalkyl, and as this alkyl or cycloalkyl, the groups described above can be mentioned as the first substituent respectively. In particular, alkyl having 1 to 5 carbon atoms (for example, methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl) is preferable.

[0080] This regulation can be expressed by a compound having a ring structure in which X represented by the following formula (1-3-1) 1 or X 2 is incorporated into the condensed ring B' and the condensed ring C'. That is, for example, for the B ring (or C ring) which is a benzene ring, X 1 (or X 2 ) is incorporated, and a compound having a B' ring (or C' ring) formed by condensation of another ring is formed. The formed condensed ring B' (or condensed ring C') is, for example, a carbazole ring, a phenoxazine ring, a phenothiazine ring or an acridine ring.

[0081] Further, the above regulation can also be expressed by a compound having a ring structure in which any one of X represented by the following formula (1-3-2) and formula (1-3-3) 1 and X 2 is incorporated into the condensed ring A'. That is, for example, for the A ring which is a benzene ring, any one of X 1 and X 2 is incorporated, and a compound having an A' ring formed by condensation of another ring is formed. The formed condensed ring A' is, for example, a carbazole ring, a phenoxazine ring, a phenothiazine ring or an acridine ring.

[0082]

Chemical formula

[0083] As an example, it is also preferable that R of the >N-R is cycloalkyl which may be substituted, and it is bonded to the A ring, the B ring or the C ring by a single bond. As the cycloalkyl, cyclohexyl which may be substituted or cyclohexyl which may be substituted is preferable.

[0084] As a particularly preferred example of the condensed ring formed as described above, a structure represented by the formula (A11) can be given. As described above, in this case, the two carbons substituted with methyl groups are asymmetric carbons, and as the compound represented by the formula (1), diastereomers and enantiomers may exist. However, as the compound represented by the formula (1), any of these isomers may be used, or a form in which possible isomers are mixed in an arbitrary ratio may also be used.

[0085]

Chemical formula

[0086] In the formula (A11), Me is methyl, and at the positions of the two *, X 1 or X 2 is bonded to one of the two rings to which it is bonded, and at the position of **, it is bonded to the other ring. Examples of such a structure include the structures of the compounds represented by any of the following formulas (1-17), (1-32), (1-56), and (1-72).

[0087] When the compound of the present invention having >N-R which is R in the above preferred range as X 1 or X 2 is used as a light-emitting material in the manufacture of an element, the light-emitting efficiency and the element life can be further improved.

[0088] X of the formula (1) 1 or X 2>In Si(-R)2, R is hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkyl or optionally substituted cycloalkyl. Here, as the substituent when substituted, the above-described second substituent can be mentioned. As this aryl, heteroaryl, alkyl or cycloalkyl, the groups described above as the first substituent can be mentioned respectively. Particularly, aryl having 6 to 10 carbon atoms (for example, phenyl, naphthyl, etc.), heteroaryl having 2 to 15 carbon atoms (for example, carbazolyl, etc.), alkyl having 1 to 5 carbon atoms (for example, methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl) are preferable.

[0089] X of formula (1) 1 or X 2 >In C(-R)2, R is hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkyl or optionally substituted cycloalkyl. Here, as the substituent when substituted, the above-described second substituent can be mentioned. As this aryl, heteroaryl, alkyl or cycloalkyl, the groups described above as the first substituent can be mentioned respectively. Particularly, aryl having 6 to 10 carbon atoms (for example, phenyl, naphthyl, etc.), heteroaryl having 2 to 15 carbon atoms (for example, carbazolyl, etc.), alkyl having 1 to 5 carbon atoms (for example, methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl) are preferable.

[0090] Next, the group represented by formula (G) in formula (1) will be described.

[0091] In formula (G), L is a single bond, alkylene, cycloalkylene, arylene or heteroarylene. Examples of "alkylene", "cycloalkylene", "arylene" and "heteroarylene" include divalent groups obtained by removing one hydrogen from "alkyl", "cycloalkyl", "aryl" and "heteroaryl" in this specification. As L, a single bond, arylene or heteroarylene is preferable, a single bond or arylene is preferable, and a single bond is most preferable. Also, at least one hydrogen of "alkylene", "cycloalkylene", "arylene" and "heteroarylene" may be substituted, and examples of the substituent at this time include substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), substituted or unsubstituted diheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group), substituted or unsubstituted arylheteroarylamino (aryl and heteroaryl may not be bonded to each other or may be bonded via a linking group), substituted or unsubstituted diarylboril (the two aryls may not be bonded to each other or may be bonded via a single bond or a linking group), substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted arylthio, or substituted silyl. However, an unsubstituted form of L is also preferable. Regarding the second substituent with respect to these first substituents, the above description can be referred to.

[0092] In formula (G), the (G-A) ring and the (G-B) ring are a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring. Regarding the preferable range and substituents, the description regarding the A ring, B ring and C ring in formula (1) above can be referred to, but a substituted or unsubstituted benzene ring is preferable.

[0093] In formula (G), X 3and X 4 are each independently >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se; R in >N-R is hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl; R in >C(-R)2 and >Si(-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 >C(-R)2 and >Si(-R)2 may be bonded to each other to form a ring.

[0094] Also in formula (G), X 3 and X 4 as at least one of >N-R, >C(-R)2 and >Si(-R)2 may be bonded to at least one of the (G-A) ring and (G-B) via a linking group or a single bond. Preferred linking groups are -O-, -S-, or -C(-R 14 )2-. In the case of the "-C(-R 14 )2-", R 14 is hydrogen, alkyl or cycloalkyl, and examples of this alkyl or cycloalkyl as the first substituent include the groups described above. In particular, alkyl having 1 to 5 carbon atoms (such as methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl) is preferred.

[0095] The polycyclic aromatic compound of the present invention is a polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1) and formula (2) described below. Examples of the polycyclic aromatic compound having a structure composed of one of the above structural units include the polycyclic aromatic compounds represented by the formulas described above as the structural unit represented by formula (1). Examples of the polycyclic aromatic compound having a structure composed of two or more of the structural units represented by formula (1) include compounds corresponding to multimers of the polycyclic aromatic compounds represented by the formulas described above as the structural unit represented by formula (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 (A ring, B ring or C ring) contained in the above structural unit by a plurality of unit structures, or may be in a form bonded so that any rings (A ring, B ring or C ring) contained 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 preferable.

[0096] At least one selected from the group consisting of an aryl ring and a heteroaryl ring in the polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1) is condensed with at least one cycloalkane. The same applies to the polycyclic aromatic compound represented by formula (2) described below, and the following description also applies to the polycyclic aromatic compound represented by formula (2).

[0097] The cycloalkane may be a cycloalkane having 3 to 24 carbon atoms. At least one hydrogen in the cycloalkane at this time may be substituted with an aryl having 6 to 30 carbon atoms, a heteroaryl having 2 to 30 carbon atoms, an alkyl having 1 to 24 carbon atoms or a cycloalkyl having 3 to 24 carbon atoms, and at least one -CH2- in the cycloalkane may be substituted with -O-, but a cycloalkane in which all are -CH2- is preferable.

[0098] 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 the formula (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 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.

[0099] 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, cycloalkanes having 6 carbon atoms, and the like.

[0100] Specific examples of the cycloalkane include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornene, bicyclo[1.0.1]butane, bicyclo[1.1.1]pentane, bicyclo[2.0.1]pentane, bicyclo[1.2.1]hexane, bicyclo[3.0.1]hexane, bicyclo[2.1.2]heptane, bicyclo[2.2.2]octane, adamantane, diamantane, decahydronaphthalene, and decahydroazulene, and their C1-C5 alkyl (especially methyl) substituents, halogen (especially fluorine) substituents, deuterium substituents, and the like.

[0101] Among these, for example, in the case of the following structural formula, a structure in which at least one hydrogen at the α-position carbon of cycloalkane (in cycloalkyl condensed to an aryl ring or a heteroaryl ring, the carbon at the position adjacent to the carbon of the condensation site, corresponding to the benzylic position) is substituted 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. This is to protect chemically active sites and improve the durability of the compound. Examples of this substituent include alkyl (especially methyl) substituents having 1 to 5 carbon atoms, halogen (especially fluorine) substituents, and deuterium substituents. In particular, it is preferable that a partial structure represented by the following formula (Z-11) is bonded to adjacent carbon atoms in the aryl ring or heteroaryl ring.

[0102]

Chemical formula

[0103] 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 carbon that constitutes the benzene ring and does not constitute the cycloalkane. Cycloalkanes condensed as in formula (Cy-1-4) and formula (Cy-2-4) may be further condensed. The same applies even when the condensed ring (group) is another aryl ring or heteroaryl ring other than the benzene ring (phenyl), or when the condensed cycloalkane is a cycloalkane other than cyclopentane or cyclohexane.

[0104]

Chemical formula

[0105] At least one -CH2- in the cycloalkane may be replaced by -O-. 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 condensed ring (group) is another aromatic ring or heteroaromatic ring other than the benzene ring (phenyl), or when the condensed cycloalkane is a cycloalkane other than cyclopentane or cyclohexane.

[0106]

Chemical formula

[0107] At least one hydrogen in the cycloalkane may be substituted, and examples of such substituents include aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or are bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or are bonded via a single bond or a linking group), arylheteroarylamino (the aryl and heteroaryl are not bonded to each other or are bonded via a single bond or a linking group), diarylboryl ((the two aryls are not bonded to each other or are bonded via a single bond or a linking group), alkyl, cycloalkyl, alkoxy, aryloxy, substituted silyl, deuterium, cyano or halogen, and the details of these can cite the description of the above-mentioned first substituent. 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. Further, when the cycloalkyl substitutes, a substitution form forming a spiro structure may also be used, and an example of this is shown below.

[0108]

Chemical formula

[0109] As the form of cycloalkane condensation, first, in a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1), the aryl ring and heteroaryl ring in each of ring A, ring B, and ring C, the aryl ring and heteroaryl ring in (ring a, ring b, ring c in formula (2) described later), and the aryl ring and heteroaryl ring in the condensed ring are in a form condensed with cycloalkane.

[0110] As another form of cycloalkane condensation, a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1), and a polycyclic aromatic compound represented by formula (2) described later, for example, >N-R where R is an aryl condensed with cycloalkane, diarylamino condensed with cycloalkane (the two aryls may not be bonded to each other or may be bonded via a linking group, and this is condensed to the aryl moiety), carbazolyl condensed with cycloalkane (condensed to this benzene ring moiety), or benzocarbazolyl condensed with cycloalkane (condensed to this benzene ring moiety) are exemplified. For "diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group)", the groups described as the above "first substituent" are exemplified.

[0111] In a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) and a polycyclic aromatic compound represented by formula (2) described later, the above cycloalkane condensation is preferably in a form condensed to ring A(a), ring B(b), or ring C(c), and more preferably in a form condensed to ring A(a) and ring B(b). Also, a form condensed to both ring A(a) and ring B(b) is also preferred.

[0112] 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 becomes possible to apply it to the fabrication of elements using a coating process. However, the present invention is not particularly limited to these principles. Therefore, in the polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1) and the polycyclic aromatic compound represented by formula (2) described later, it is preferable that the above cycloalkane condensation is introduced.

[0113] In the structure composed of one or more of the structural units represented by formula (1), all or part of the hydrogens may be deuterium, cyano, or halogen. The same applies to the polycyclic aromatic compound represented by formula (2) described later, and the following description also applies equally to the polycyclic aromatic compound represented by formula (2).

[0114] For example, in the structure composed of one or more of the structural units represented by formula (1), ring A, ring B, ring C (rings A to C are aryl rings or heteroaryl rings), substituents on rings A to C, Y 1 when is Si-R or Ge-R, R (= alkyl, cycloalkyl, aryl), and X 1 and X 2When >N-R, >C(-R)2, or >Si(-R)2, the hydrogen in R (= alkyl, cycloalkyl, aryl) can be substituted with deuterium, cyano, or halogen. Among these, there are embodiments in which all or some of the hydrogens in aryl or heteroaryl are substituted with deuterium, cyano, or halogen. 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 preferable that all or some of the hydrogens in the structure composed of one or more structural units represented by formula (1) are deuterated, and it is also preferable that all are deuterated.

[0115] Preferable examples of the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) include the polycyclic aromatic compound represented by the following formula (2). Regarding the substituents, the structure of the rings contained, and the preferable ranges in formula (2), each description of the corresponding formula (1) can be referred to.

[0116]

Chemical formula

[0117] In formula (2), Y 1 has the same meaning as Y in formula (1) 1

[0118] In formula (2), Z is independently N or C-R 11 and the C-R 11 of 11Each is independently hydrogen, aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or are bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or are bonded via a linking group), arylheteroarylamino (the aryl and heteroaryl are not bonded to each other or are bonded via a linking group), diarylboril (the two aryls are not bonded to each other or are bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio or substituted silyl, and at least one hydrogen in these may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl or substituted silyl. For details of the substituents listed here, reference can be made to the descriptions of the above first substituent and second substituent.

[0119] Two adjacent Rs 11 may be bonded to each other to form an aryl ring or a heterolyl ring, and the formed aryl ring and heterolyl ring may each be substituted with aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or are bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or are bonded via a linking group), arylheteroarylamino (the aryl and heteroaryl are not bonded to each other or are bonded via a linking group), diarylboril (the two aryls are not bonded to each other or are bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl or substituted silyl. For details of the substituents listed here, reference can be made to the descriptions of the above first substituent and second substituent.

[0120] In formula (2), Z=Z may each independently be >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, and it is more preferably >O, >N-R, >C(-R)2, or >S. R in the >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 may be substituted with aryl, heteroaryl, diarylamino, alkyl, cycloalkyl, or substituted silyl. Also, two Rs in the >C(-R)2 and >Si(-R)2 may be bonded to each other to form a ring. For details of the substituents listed here, reference can be made to the descriptions of the above first substituent and second substituent.

[0121] In the b-ring, c-ring, etc., examples of the ring obtained by replacing the "Z=Z" part 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. Further, when the remaining Zs are adjacent and they are C-R 11 and its R 11 are bonded to form a benzene ring, an indene ring, an indole ring, a benzofuran ring, or a benzothiophene ring can be formed. The formed ring may have a substituent. In the b-ring, etc., an example where one Z=Z is >N-R, >O, >S, >C(-R)2 and the remaining Z is C-H, and an example where one Z=Z is >N-R, >O, >S, >C(-R)2 and the remaining Zs are adjacent and both are C-R 11 and these Rs 11 are bonded to each other to form a benzene ring are shown below. However, the forms that the b-ring, c-ring, etc. can take are not limited to the following examples.

[0122]

Chemical formula

[0123] Also, R of C-R 11 its R 11Combine to form aryl rings and heteroaryl rings such as a bicyclopentadiene ring, pyrrole ring, furan ring, thiophene ring, indene ring, indole ring, benzofuran ring, or benzothiophene ring. Examples are shown below. [Chemical formula]

[0124] In the above example, regarding the b-ring bonded to Y 1 and X 1 in formula (1), examples are given, but this explanation can also be similarly applied to the a-ring or c-ring in formula (2).

[0125] X 1 and X 2 in formula (2) are each independently >O, >N-R, >Si(-R)2, >C(-R)2, >S, >Se, or >N-R (>N-G) where R is a monovalent group represented by formula (G-2). However, at least one of X 1 and X 2 is >N-G. Regarding the specific ranges etc. of >N-R, >Si(-R)2, and >C(-R)2, reference can be made to the description regarding X 1 and X 2 in the above formula (1). When either X 1 , X 2 is >N-G, the other X 1 , X 2 is preferably >N-G, >N-R, >C(-R)2, or >O, and more preferably >N-G or >N-R.

[0126] X 1 and X 2 in formula (1)In >N-R, >Si(-R)2 and >C(-R)2, at least one of the Rs may be bonded to at least one of Ring A and Ring B, or at least one of Ring A and Ring C, via a linking group or a single bond. In formula (2), this above description corresponds to the provision that "R in >N-R, at least one of the Rs in >C(-R)2 and >Si(-R)2 is bonded to one or two of the Cs in Z which is C-R 13 )2- or a single bond, and is bonded to C-R 11 in C of one of the Cs in Z which is C-R 11 in Z which is C (carbon atom). Specifically, the above R may be bonded to the C (carbon atom) in the spatially closest C-R 1 in each of the rings shown below. R in >N-R, >Si(-R)2 or >C(-R)2 as X 11 in formula (2) may be bonded to the C (carbon atom) in the spatially closest C-R 1 in at least one of Ring a and Ring b via a linking group or a single bond, and R in >N-R, >Si(-R)2 or >C(-R)2 as X 11 may be bonded to the C (carbon atom) in the spatially closest C-R 13 in at least one of Ring a and Ring c via a linking group or a single bond. Regarding R 13 in "-C(-R

[0127] In formula (2), the number of rings (monocyclic rings) 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 each of the above formulas, it is also preferable that all Zs are C-R 11 in each case.

[0128] In formula (2), in the ring (monocyclic ring) containing Z which is N, it is preferable that one or two of the plurality of Z's are N, and when two of them are N, it is preferable that the two N's 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 preferable, and a pyridine ring or a pyrimidine ring is more preferable. When the 5-membered ring is a ring containing Z which is N, a thiazole ring or an oxazole ring is preferable.

[0129] The group represented by formula (G-2) in formula (2) will be described. In formula (G-2), Z G is N or C-R 12 and the R 12 of the C-R 12 are each independently hydrogen, aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or are bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or are bonded via a linking group), arylheteroarylamino (the aryl and the heteroaryl are not bonded to each other or are bonded via a linking group), diarylboryl (the two aryls are not bonded to each other or are bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio or substituted silyl, and at least one hydrogen in these may be substituted with aryl, heteroaryl, arylamino, alkyl, cycloalkyl, or substituted silyl. For details of the substituents listed here, reference can be made to the descriptions of the above first substituent and second substituent.

[0130] Two adjacent R's 12They may be joined to each other to form an aryl ring or a heteroaryl ring, and each of the formed aryl ring and heteroaryl ring may be substituted with aryl, heteroaryl, diarylamino (the two aryls are not bonded to each other or are bonded via a linking group), diheteroarylamino (the two heteroaryls are not bonded to each other or are bonded via a linking group), arylheteroarylamino (the aryl and heteroaryl are not bonded to each other or are bonded via a linking group), diarylboryl (the two aryls are not bonded to each other or are bonded via a single bond or a linking group), alkyl, cycloalkyl, alkenyl, alkoxy, aryloxy, arylthio, or substituted silyl, and at least one hydrogen in these may be substituted with aryl, heteroaryl, arylamino, alkyl, cycloalkyl, or substituted silyl. For details of the substituents listed here, reference can be made to the descriptions of the first substituent and the second substituent above.

[0131] In formula (G-2), Z G =Z G may each independently be >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, and more preferably >O, >N-R, >C(-R)2, or >S. R in the >N-R, the >C(-R)2, and the >Si(-R)2 is each independently hydrogen, aryl, heteroaryl, alkyl, or cycloalkyl, and at least one hydrogen in these may be substituted with aryl, heteroaryl, arylamino, alkyl, cycloalkyl, or substituted silyl. The two Rs in the >C(-R)2 and the >Si(-R)2 may be joined to each other to form a ring. For details of the substituents listed here, reference can be made to the descriptions of the first substituent and the second substituent above.

[0132] In formula (G-2), the "Z G =Z GRegarding the ring obtained by replacing the position of "」" with >O, >N-R, >C(-R)2, >Si(-R)2, >S, or >Se, the description regarding "Z=Z" in the a-ring and b-ring in the above formula (1) can be referred to. Also, regarding its specific form, the above description can be referred to by reading Y 1 and X 1 as X 3 and X 4 instead.

[0133] X in formula (G-2) 3 and X 4 The -O-, -S-, -C(-R 14 )2- or single bond of >N-R, >Si(-R)2, and >C(-R)2 in can be bonded to one or two of the C's in C-R 12 which is Z G . This corresponds to the description in formula (1) that "at least one R of >N-R, >C(-R)2, and >Si(-R)2 may be bonded to at least one of the (G-A) ring and (G-B) via a linking group or a single bond". Specifically, the above R in formula (G-2) is the C-R 12 which is Z G The C (carbon atom) of can be bonded by -O-, -S-, -C(-R 13 )2- or a single bond. Among these, the R 14 of "-C(-R 14 )2-" is hydrogen, alkyl, or cycloalkyl, and as this alkyl or cycloalkyl, the groups described above as the first substituents can be mentioned respectively. In particular, alkyl having 1 to 5 carbon atoms (for example, methyl, ethyl, etc.) or cycloalkyl having 5 to 10 carbon atoms (preferably cyclohexyl or adamantyl) is preferable.

[0134] In formula (G-2), one bond of the divalent group L is linked to any Z G (Z G which is C-R 12 of the C (carbon atom)) in the (G-a) ring, and the other bond is linked to the N (nitrogen atom) of >N-G.

[0135] In formula (G-2), the number of rings (monocyclic rings) containing Z which is N is from 0 to 4, preferably from 0 to 3, more preferably from 0 to 2, and particularly preferably from 0 to 1. In each of the above formulas, all Z are C-R Z It is also preferable that it is.

[0136] In the ring (monocyclic ring) containing Z which is N in formula (G-2), it is preferable that one or two of the plurality of Z are N. When two Z are N, it is preferable 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 preferable, and a pyridine ring or a pyrimidine ring is more preferable. When the 5-membered ring is a ring containing Z which is N, a thiazole ring and an oxazole ring are preferable.

[0137] Specific examples of the group represented by formula (G-2) include, but are not limited to, the forms described by the following formulas (G-2-1) to (G-2-16).

[0138]

Chemical formula

[0139] In formulas (G-2-1) to (G-2-16), R can be referred to as the R defined for >N-R, >Si(-R)2 and >C(-R)2 in the above X 3 and X 4 For at least one hydrogen of these groups, a substituent may be substituted, and for the form of substitution, the description of the above first substituent and second substituent can be referred to.

[0140] Further specific examples of the polycyclic aromatic compound represented by formula (1) of the present invention include the following compounds. In the following structural formulas, "Me" represents methyl, "tBu" represents t-butyl, "tAm" represents t-amyl, and "D" represents deuterium. Note that the following structure is an example.

[0141]

Chem.

[0142]

Chem.

[0143]

Chem.

[0144]

Chem.

[0145]

Chem.

[0146]

Chem.

[0147]

Chem.

[0148]

Chem.

[0149] The polycyclic aromatic compound of the present invention can be produced by the following procedure.

[0150] <Method for Producing Polycyclic Aromatic Compound> Having a structure consisting of one or more structural units represented by formula (1) or formula (2), basically, first, the A ring (a ring), the B ring (b ring), and the C ring (c ring) are combined with a linking group (X 1 or X 2By bonding with a group containing), an intermediate is produced (the first reaction). Thereafter, the A ring (a ring), the B ring (b ring), and the C ring (c ring) are bonded with a bonding group (Y 1 to produce the final product (the second reaction). In the first reaction, for example, in the case of an etherification reaction, general reactions such as a nucleophilic substitution reaction and a Ullmann reaction can be used. In the case of an amination reaction, general reactions such as a Buchwald-Hartwig reaction can be used. In the second reaction, a tandem hetero Friedel-Crafts reaction (successive aromatic electrophilic substitution reaction, the same applies hereinafter) can be used. Somewhere in the reaction process, by using a raw material having a desired condensed ring or adding a step of condensing a ring, at least one ring selected from the group consisting of the A ring, the B ring, and the C ring is a monocyclic aryl ring, a monocyclic heteroaryl ring, and a cyclopentadiene ring. A compound can be produced with a condensed ring composed of two or more rings selected from the group consisting of.

[0151] <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.

[0152] Using an organic alkali compound, X in the following intermediate-1 1 and X 2 A reaction step of metallizing the halogen atom (Hal) between and Y 1 Halide of, Y 1 Aminated halide of, Y 1 Alkoxylated product of and Y 1 A reaction step of exchanging the metal with Y using a reagent selected from the group consisting of aryloxylated products of and Y 1 and a reaction step of bonding the B ring and the C ring with the Y using a Brønsted base by a successive aromatic electrophilic substitution reaction are described below. 1

[0153]

Chemical formula

[0154] As metalating reagents used in the halogen-metal exchange reaction in the scheme described so far, there are alkyl lithiums 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.

[0155] In addition to the above reagents, as metalating reagents used in the ortho-metal exchange reaction in the scheme described so far, there are organo-alkali compounds such as lithium diisopropylamide, lithium tetramethylpiperidide, lithium hexamethyldisilazide, potassium hexamethyldisilazide, lithium tetramethylpiperidinylmagnesium chloride·lithium chloride complex, and lithium tri-n-butylmagnesate.

[0156] Furthermore, as additives for accelerating the reaction when using alkyl lithium as the metalating reagent, there are N,N,N’,N’-tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, N,N-dimethylpropyleneurea, etc.

[0157] In addition, as Lewis acids used in the scheme described so far, there are 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, etc. Also, those obtained by supporting these Lewis acids on a solid can be used in the same way.

[0158] In addition, examples of Brønsted 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, etc. Examples of solid Brønsted acids include Amberlyst (trade name: Dow Chemical), Nafion (trade name: DuPont), zeolite, Teica Cure (trade name: Teica Corporation), etc.

[0159] 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, etc.

[0160] In addition, examples of 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, etc.

[0161] 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.

[0162] In the above scheme, a Brønsted base or a Lewis acid may be used to promote the tandem hetero Friedel-Crafts reaction. However, the trifluoride of Y 1 of Y1 trichloride of, Y 1 tribromide of, Y 1 triiodide of, Y such as 1 When using a halide of, with the progress of the aromatic electrophilic substitution reaction, acids such as hydrogen fluoride, hydrogen chloride, hydrogen bromide, and hydrogen iodide are generated. Therefore, the use of a Bronsted base that captures the acid is effective. On the other hand, Y 1 amino halide of, Y 1 When using an alkoxide of, with the progress of the aromatic electrophilic substitution reaction, amines and alcohols are generated. 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 their elimination is effective.

[0163] Further, the polycyclic aromatic compound of the present invention includes compounds in which at least some hydrogen atoms are substituted with deuterium or cyano, or compounds substituted with halogens such as fluorine and chlorine. Such compounds can be synthesized in the same manner as above by using raw materials in which the desired positions are deuterated, cyanated, fluorinated, or chlorinated.

[0164] <2. Organic Device> The polycyclic aromatic compound of the present invention can be used as a material for an organic device. Examples of the organic device include an organic electroluminescent element, an organic field effect transistor, or an organic thin film solar cell.

[0165] The polycyclic aromatic compound and its multimer according to the present invention can be used as a material for organic devices. Examples of the organic device include an organic electroluminescent element, an organic field effect transistor, or an organic thin film solar cell, etc., and an organic electroluminescent element is preferable. The polycyclic aromatic compound and its multimer according to the present invention are preferably an organic electroluminescent element material, more preferably a material for a light emitting layer (light emitting material), and most preferably a dopant material for a light emitting layer. In particular, in an organic electroluminescent element, as a dopant material for a light emitting layer, in a polycyclic aromatic compound having a structure composed of one or more structural units represented by the formula (1) of the present invention or the formula (2) described later, Y 1 is B, X 1 and X 2 wherein any one of them is >N-G and the other is >N-G, >N-R or >O is preferable, and a compound being >N-G or >N-R is more preferable. As a host material for a light emitting layer, Y 1 is B, X 1 and X 2 wherein any one of them is >N-G and the other is >N-R or >O is preferable, Y 1 is B, X 1 and X 2 wherein any one of them is >N-G and the other is >O is more preferable. As an electron transport material, a compound in which Y 1 is B or P=O is preferably used.

[0166] <2-1. Organic electroluminescent element> <2-1-1. 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.

[0167] Incidentally, the organic EL element 100 may have a structure in which the manufacturing order is reversed. For example, it may include 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.

[0168] Not all of the above layers are essential. With a minimum structural unit consisting 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 optionally provided layers. Also, each of the above layers may consist of a single layer or a plurality of layers.

[0169] As aspects of the layers constituting the organic EL element, in addition to the above-described structural aspect of "substrate / anode / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode", there are also "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" structural aspects.

[0170] <2-1-2. 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 emission (fluorescence) 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 it is preferably used as a material for the light-emitting layer, and more preferably used as a dopant material.

[0171] In addition, as the dopant, there is an example of using an assisting dopant and an emitting dopant in combination, but in this specification, when simply described as "dopant", it refers to the emitting dopant used alone.

[0172] 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 co-evaporation with the host material, but it may also be co-evaporated after being premixed with the host material.

[0173] The amount of the host material used varies depending on the type of the host material, and it 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.

[0174] The amount of dopant material used varies depending on the type of dopant material and may be determined according to the characteristics of the dopant material. The standard amount of dopant used is preferably 0.001 to 50% by mass, more preferably 0.05 to 20% by mass, and even more preferably 0.1 to 10% by mass of the total material for the light-emitting layer. If it is within the above range, for example, it is preferable in that it can prevent the concentration quenching phenomenon.

[0175] <Host material> Examples of host materials 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, and benzofluorene derivatives.

[0176] 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

[0177] 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 compounds represented by the above formulas may be substituted with an alkyl having 1 to 6 carbon atoms, cyano, halogen, or deuterium.

[0178] 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.

[0179] [Chemistry] (mCP)

[0180] [Chemistry]

[0181] [Chemistry]

[0182] [Chemistry]

[0183] <Anthracene compound> Examples of the anthracene compound as a host include a compound represented by formula (3-H) and a compound represented by formula (3-H2). [Chemistry]

[0184] In formula (3-H), X and Ar 4 are each independently hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), optionally substituted diheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group), optionally substituted arylheteroarylamino (aryl and heteroaryl may not be bonded to each other or may be bonded via a single bond or a linking group), 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 Ar4 It will not become hydrogen at the same time, 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.

[0185] Also, 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 this X include a single bond, arylene (such as phenylene, biphenylene, and naphthylene), and heteroarylene (groups 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).

[0186] Details of each group in the compound represented by formula (3-H) can cite the description in the above formula (1), and will be further described in the column of the following preferred embodiments.

[0187] Preferred embodiments of the above anthracene compound will be described below. The definitions of the symbols in the following structures are the same as the above definitions. [Chemical formula]

[0188] In formula (3-H), each X is 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).

[0189] In addition, 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. 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).

[0190] 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

[0191] 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). 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 *.

[0192] 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). When 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).

[0193] 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). In addition, 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 *. 3 and is bonded.

[0194] Ar 4 is, independently of each other, hydrogen, phenyl, biphenylyl, terphenylyl, 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.

[0195] Examples of the alkyl having 1 to 4 carbon atoms that substitutes the silyl include methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl, cyclobutyl, etc., and the three hydrogens in the silyl are each independently substituted with these alkyls.

[0196] Specific examples of "silyl substituted with an alkyl having 1 to 4 carbon atoms" 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.

[0197] 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, and the three hydrogens in silyl are each independently substituted with these cycloalkyls.

[0198] Specific examples of "silyl substituted with a cycloalkyl having 5 to 10 carbon atoms" include tricyclopentylsilyl, tricyclohexylsilyl, and the like.

[0199] Examples of the substituted silyl also include 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.

[0200] In addition, the hydrogen in the chemical structure of the anthracene compound represented by formula (3-H) may be substituted with a group represented by formula (A). When substituted with the group represented by formula (A), the group represented by formula (A) substitutes at least one hydrogen in the compound represented by formula (3-H) therein.

[0201] The group represented by formula (A) is one of the substituents that the anthracene compound represented by formula (3-H) may have.

Chemical formula

[0202] In formula (A), Y is -O-, -S- or >N-R 29 and 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 adjacent groups may be bonded to each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring, and R 29 is hydrogen or optionally substituted aryl. Y in formula (A) is preferably -O-.

[0203] R 21 ~R 28In the formula, the "alkyl" in the "optionally substituted alkyl" may be either linear or branched, and examples thereof include 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 still more preferred, and alkyl having 1 to 4 carbon atoms (branched alkyl having 3 to 4 carbon atoms) is particularly preferred.

[0204] 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, and the like.

[0205] R 21 ~R 28 In the formula, the "cycloalkyl" in the "optionally substituted cycloalkyl" includes cycloalkyl having 3 to 24 carbon atoms, cycloalkyl having 3 to 20 carbon atoms, cycloalkyl having 3 to 16 carbon atoms, cycloalkyl having 3 to 14 carbon atoms, cycloalkyl having 5 to 10 carbon atoms, cycloalkyl having 5 to 8 carbon atoms, cycloalkyl having 5 to 6 carbon atoms, cycloalkyl having 5 carbon atoms, and the like.

[0206] Specific "cycloalkyl" includes 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, etc.

[0207] R 21 ~R 28 Examples of the "aryl" in the "optionally substituted aryl" in R~R include aryl having 6 to 30 carbon atoms, preferably aryl having 6 to 16 carbon atoms, more preferably aryl having 6 to 12 carbon atoms, and particularly preferably aryl having 6 to 10 carbon atoms.

[0208] Specific "aryl" includes 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, etc.

[0209] R 21 ~R 28 Examples of the "heteroaryl" in the "optionally substituted heteroaryl" in R~R include heteroaryl having 2 to 30 carbon atoms, preferably heteroaryl having 2 to 25 carbon atoms, more preferably heteroaryl having 2 to 20 carbon atoms, still more preferably heteroaryl having 2 to 15 carbon atoms, and particularly preferably heteroaryl 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.

[0210] Specific examples of the "heteroaryl" include, 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 and the like.

[0211] R 21 ~R 28 Examples of the "alkoxy" in the "optionally substituted alkoxy" for R~R 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 4 carbon atoms (branched alkoxy having 3 to 4 carbon atoms) is particularly preferred.

[0212] Specific examples of the "alkoxy" include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy and the like.

[0213] R 21 ~R 28The "aryloxy" in "optionally substituted aryloxy" is a group in which the hydrogen of the -OH group is substituted by aryl, and this aryl is the group described as R 21 ~R 28 as described for "aryl" above.

[0214] R 21 ~R 28 The "arylthio" in "optionally substituted arylthio" is a group in which the hydrogen of the -SH group is substituted by aryl, and this aryl is the group described as R 21 ~R 28 as described for "aryl" above.

[0215] R 21 ~R 28 The "trialkylsilyl" in [R 21 ~R 28 is a group in which the three hydrogens in the silyl group are each independently substituted by alkyl, and this alkyl can be the group described as "alkyl" above. Preferred alkyls for substitution are alkyls having 1 to 4 carbon atoms, specifically including methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl, cyclobutyl, etc.

[0216] 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.

[0217] R 21 ~R 28 Examples of the "tricycloalkylsilyl" group in formula (1) include groups in which the three hydrogens in the silyl group are each independently substituted with a cycloalkyl group, and this cycloalkyl group may be the same as the cycloalkyl group described for R 21 ~R 28 above. Preferred cycloalkyl groups for substitution are cycloalkyl groups having 5 to 10 carbon atoms, and specific examples include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, bicyclo[1.1.1]pentyl, bicyclo[2.0.1]pentyl, bicyclo[1.2.1]hexyl, bicyclo[3.0.1]hexyl, bicyclo[2.1.2]heptyl, bicyclo[2.2.2]octyl, adamantyl, decahydronaphthalenyl, decahydroazulenyl, and the like.

[0218] Specific examples of the "tricycloalkylsilyl" group include tricyclopentylsilyl, tricyclohexylsilyl, and the like.

[0219] Specific examples of a dialkylcycloalkylsilyl substituted with two alkyls and one cycloalkyl and an alkyldicycloalkylsilyl substituted with one alkyl and two cycloalkyls include silyls substituted with groups selected from the specific alkyls and cycloalkyls described above.

[0220] R 21 ~R 28 Examples of the "substituted amino" of the "optionally substituted amino" in R 21 ~R 28 include, for example, an amino in which two hydrogens are substituted with aryl or heteroaryl. An amino in which two hydrogens are substituted with aryl is a diaryl (the two aryls may not be bonded to each other or may be bonded via a linking group) substituted amino, an amino in which two hydrogens are substituted with heteroaryl is a diheteroaryl substituted amino, and an amino in which two hydrogens are substituted with aryl and heteroaryl is an arylheteroaryl substituted amino. This aryl or heteroaryl can cite the groups described as the "aryl" or "heteroaryl" in R

[0221] Specific examples of the "substituted amino" include diphenylamino, dinaphthylamino, phenylnaphthylamino, dipyridylamino, phenylpyridylamino, naphthylpyridylamino, and the like.

[0222] R 21 ~R 28 Examples of the "halogen" in R

[0223] R 21 ~R 28 Among the groups described as R 21 ~R 28The groups described as "alkyl", "cycloalkyl", "aryl" or "heteroaryl" in [reference] can be cited.

[0224] For ">N-R" as Y 29 R in 29 is hydrogen or aryl which may be substituted. As this aryl, the groups described as "aryl" in R 21 ~R 28 in [reference] can be cited, and as its substituents, the groups described as substituents for R 21 ~R 28 in [reference] can be cited.

[0225] R 21 ~R 28 Among R

[0226]

Chemical formula

[0227] As the ring formed by adjacent groups bonding to each other, for example, a cyclohexane ring can be cited if it is a hydrocarbon ring, and as the aryl ring or heteroaryl ring, the groups described as R 21 ~R 28The ring structures described by "aryl" and "heteroaryl" in [description] are exemplified, and these rings are formed so as to be condensed with one or two benzene rings in formula (A-1).

[0228] The group represented by formula (A) is a group obtained by removing one hydrogen at any position in 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), any atom on any ring formed by the adjacent groups among R 21 ~R 28 being bonded to each other, or any position in R 29 in ">N-R 29 " as Y in the structure of formula (A), or any position in R 29 in ">N-R 29 " (where N(R

[0229] 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.

[0230] 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

[0231]

Chemical formula

[0232] In the compound represented by formula (3-H), the group represented by formula (A) is preferably in a form bonded to any one of the naphthalene ring in formula (3-X1) or formula (3-X2), the single bond in formula (3-X3), and Ar in formula (3-X3). 3 is preferably in a form bonded to any one of them.

[0233] Also, all or part of the hydrogen in the chemical structure of the anthracene compound represented by formula (3-H) may be deuterium.

[0234] The anthracene compound as a host may be, for example, a compound represented by the following formula (3-H2).

Chemical formula

[0235] In formula (3-H2), Ar c is an optionally substituted aryl or an optionally substituted heteroaryl, R c is hydrogen, alkyl, or cycloalkyl, Ar 11 Ar 12 Ar 13 Ar 14 Ar 15 Ar 16 Ar 17 and Ar 18is, independently of one another, hydrogen, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), optionally substituted diheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group), optionally substituted arylheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group), optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted arylthio, or optionally substituted silyl, and at least one hydrogen in the compound represented by formula (1) may be substituted with halogen, cyano, or deuterium.

[0236] In formula (3-H2), the definitions of "optionally substituted aryl", "optionally substituted heteroaryl", "optionally substituted diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group)", "optionally substituted diheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group)", "optionally substituted arylheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group)", "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 description in formula (1) can be cited.

[0237] The "optionally substituted aryl" is preferably a group represented by any one of the following formula (3-H2-X1) to formula (3-H2-X8).

[0238]

Chem.

[0239] In formulas (3-H2-X1) to (3-H2-X8), * indicates the bonding position. In formulas (3-H2-X1) to (3-H2-X3), Ar 21 , Ar 22 , and Ar 23 are each independently hydrogen, phenyl, biphenylyl, terphenylyl, quaterphenylyl, 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 compound represented by formula (3-H).

[0240] In formulas (3-H2-X4) to (3-H2-X8), Ar 24 , Ar 25 , Ar 26 , Ar 27 , Ar 28 , Ar 29 , and Ar 30 are each independently hydrogen, phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, fluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A). Also, any one or two or more hydrogens in each of the groups represented by formulas (3-H2-X1) to (3-H2-X8) may be substituted with an alkyl having 1 to 6 carbon atoms (preferably methyl or t-butyl).

[0241] Furthermore, preferred examples of the "optionally substituted aryl" include terphenyl (especially m-terphenyl-5'-yl) optionally 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).

[0242] Examples of the "heteroaryl which may be substituted" include the group represented by formula (A). In addition, specific examples of the "aryl which may be substituted" and the "heteroaryl which may be substituted" include dibenzofuryl, naphthobenzofuryl, phenyl-substituted dibenzofuryl, and the like.

[0243] 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.

[0244] 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 It is preferred that at least two of them are aryl which may be substituted or heteroaryl which may be substituted. That is, the anthracene 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.

[0245] The anthracene compound represented by formula (3-H2) has Ar 11 ~Ar 18Two of them may be substituted aryl or heteroaryl which may be substituted, and the other six are more 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 compound represented by the formula (3-H2) preferably has a structure in which substituents selected from the group consisting of aryl which may be substituted and heteroaryl which may be substituted are bonded to the anthracene ring at three positions.

[0246] In the anthracene compound represented by the formula (3-H2), Ar 11 ~Ar 18 It is more preferable that 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.

[0247] Furthermore, in the formula (3-H2), R c is hydrogen, and it is preferable that any six of Ar 11 ~Ar 18 are hydrogen.

[0248] The anthracene compound represented by the formula (3-H2) is preferably an anthracene compound represented by the following formula (3-H2-A), (3-H2-B), (3-H2-C), (3-H2-D), or (3-H2-E).

Chemical formula

[0249] In the 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' is independently phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A), and at least one hydrogen in these groups may be substituted with phenyl, biphenylyl, terphenylyl, quaterphenylyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, chrysenyl, triphenylenyl, pyrenyl, or a group represented by formula (A). Here, when all the hydrogens of 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 Ar 18 ' and on the carbon atom of the anthracene ring to which Ar

[0250] Ar c ', Ar 11 ', Ar 12 ', Ar 13 ', Ar 14 ', Ar 15 ', Ar 17 ', and Ar 18 ' are each a substituted or unsubstituted phenyl or a substituted or unsubstituted naphthyl, it is preferably a group represented by any of the above formulas (3-H2-X1) to (3-H2-X7).

[0251] Ar c ', Ar 11 ', Ar 12 ', Ar 13 ', Ar 14 ', Ar 15 ', Ar 17 ', and Ar 18' is each independently phenyl, biphenylyl (especially, biphenyl-2-yl or biphenyl-4-yl), terphenylyl (especially, 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).

[0252] Also, at least one hydrogen in the compound represented by 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. Also, the deuterated form is preferred, and the form in which the anthracene ring is all deuterated or the form in which all hydrogen atoms are deuterated is preferred.

[0253] As the anthracene compound represented by formula (3-H2) which is particularly preferred, the anthracene compound represented by the following formula (3-H2-Aa) can be mentioned. [Chemical formula]

[0254] In formula (3-H2-Aa), Ar c ’, Ar 14 ’, and Ar 15' is 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 the 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 to which they are not bonded. At least one hydrogen in the compound represented by the formula (3-H2-Aa) may be substituted with halogen or cyano, and at least one hydrogen in the compound represented by the formula (3-H2-Aa) may be substituted with deuterium.

[0255] In the formula (3-H2-Aa), Ar c ’, Ar 14 ’, and Ar 15 ’ are each independently preferably 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).

[0256] In the compound represented by the formula (3-H2-Aa), at least, the carbon at the 10-position of the anthracene ring (Ar cIt is preferable that the hydrogen atom bonded to the carbon atom to which 'is bonded (the 9-position carbon) is replaced by deuterium. That is, the compound represented by the formula (3-H2-Aa) is preferably the 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 those defined in the formula (3-H2-Aa). D in the formula (3-H2-Ab) indicates that at least this position is deuterium, and any one or more of the other hydrogen atoms in the formula (3-H2-Ab) may be deuterium at the same time. It is also preferable that all the hydrogen atoms in the formula (3-H2-Ab) are deuterium.

[0257]

Chemical formula

[0258] In addition, specific examples of the anthracene compound include, for example, compounds represented by the formula (3-131-Y) to the formula (3-182-Y), the formula (3-183-N), the formula (3-184-Y) to the formula (3-284-Y), and the formula (3-500) to the formula (3-557), and the formula (3-600) to the formula (3-605), and the formula (3-606-Y) to the formula (3-626-Y). The hydrogen atoms in these formulas may be partially or all replaced by deuterium, but the particularly preferred deuterium substitution forms are listed individually. Y in the formula is -O-, -S-, >N-R 29 (R 29 has the same definition as above) or >C(-R 30 )2(R 30 is an aryl or alkyl that may be linked), and R 29 is, for example, phenyl, and R 30 is, for example, methyl. The formula number is, for example, when Y is O, the formula (3-131-Y) is the formula (3-131-O), and when Y is -S- or >N-R 29 , they are the formula (3-131-S) or the formula (3-131-N) respectively.

[0259] [Chemistry]

[0260] [Chemistry]

[0261] [Chemistry]

[0262] [Chemistry]

[0263] [Chemistry] TIFF0007710670000067.tif145138

[0264] [Chemistry]

[0265] [Chemistry]

[0266] [Chemistry]

[0267] [Chemistry]

[0268] [Chemistry]

[0269] [Chemistry]

[0270]

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[0271]

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[0272]

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[0273]

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[0274]

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[0275]

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[0276]

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[0277]

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[0278]

Chem.

[0279] Among these compounds, those 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 (3-270-Y) to Formula (3-284-Y), Formula (3-501), Formula (3-507), Formula (3-508), Formula (3-509), Formula (3-513), Formula (3-514), Formula (3-519), Formula (3-521), Formula (3-538) to Formula (3-547) or Formula (3-600) to Formula (3-605), and Formula (3-606-Y) to Formula (3-626-Y) are preferred. Further, Y is -O- or >N-R 29 is preferred, and -O- is more preferred. Also, the deuterium substitution form is preferred.

[0280] The above anthracene compounds are compounds having a reactive group at a desired position of the anthracene skeleton and an anthracene compound represented by Formula (3-H), and for X, Ar 4 and a compound having a reactive group in a partial structure such as the structure of Formula (A) as starting materials, and can be produced by applying Suzuki coupling, Negishi coupling, and 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.

[0281] <Fluorene compound> The compound represented by Formula (4-H) basically functions as a host.

Chemical formula

[0282] In formula (4-H), R 1 to R 10 are each independently hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the fluorene skeleton in formula (4-H) via a linking group), diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), diheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group), arylheteroarylamino (the aryl and the heteroaryl may not be 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 may be 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 10They may each independently combine to form a condensed ring or a spiro ring, and at least one hydrogen in the formed ring may be substituted with aryl, heteroaryl (the heteroaryl may be bonded to the formed ring via a linking group), diarylamino (the two aryls may not be bonded to each other or may be bonded via a linking group), diheteroarylamino (the two heteroaryls may not be bonded to each other or may be bonded via a single bond or a linking group), arylheteroarylamino (the aryl and the heteroaryl may not be 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 may be 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.

[0283] For the details of each group in the definition of formula (4-H), the description of the polycyclic aromatic compound of formula (1) mentioned above can be cited.

[0284] R 1 to R 10 Examples of the alkenyl from R

[0285]

[0286]

Chem.

[0287] In formulas (4-Ar1) to (4-Ar5), Y 1 is, independently of one another, O, S or N-R, where 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 by phenyl, biphenylyl, naphthyl, anthracenyl, phenanthrenyl, methyl, ethyl, propyl, or butyl.

[0288] 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-.

[0289] 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 to R 8The condensed ring formed by [description] 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) include a naphthalene ring and a phenanthrene ring. R 9 and R 10 The spiro ring formed by [description] 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.

[0290] 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 is bonded.

[0291]

Chemical formula

[0292] 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 R 1 to R 10 in formula (4-H).

[0293] 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 compound.

[0294]

Chemical formula

[0295] 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 R 11 to R 14 in formula (4-1) and formula (4-2).

[0296] In addition, all or part of the hydrogen in the compound represented by formula (4-H) may be substituted with halogen, cyano or deuterium.

[0297] More specific examples of the fluorene compound as the host of the present invention include compounds represented by the following structural formulas. Note that "Me" represents methyl.

Chemical formula

[0298] <Dibenzocrisene compound> The dibenzocrisene compound as the host is, for example, a compound represented by the following formula (5-H).

Chemical formula

[0299] 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 may be substituted with aryl, heteroaryl, alkyl or cycloalkyl, and R 1 to R 16 among them, adjacent groups may be bonded to form a condensed ring, and at least one hydrogen in the formed ring may be 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 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 may be substituted with aryl, heteroaryl, alkyl or cycloalkyl, and at least one hydrogen in the compound represented by formula (5-H) may be substituted with halogen, cyano or deuterium.

[0300] Details of each group in the definition of formula (5-H) can cite the description in the polycyclic aromatic compound of formula (1) described above.

[0301] Examples of the alkenyl in the definition of formula (5-H) include alkenyl having 2 to 30 carbon atoms, preferably alkenyl having 2 to 20 carbon atoms, more preferably alkenyl having 2 to 10 carbon atoms, still more preferably alkenyl having 2 to 6 carbon atoms, and particularly preferably alkenyl 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.

[0302] Specific examples of the heteroaryl also include 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).

[0303]

Chemical formula

[0304] In formulas (5-Ar1) to (5-Ar5), Y 1 is each independently O, S, or N-R, where R is phenyl, biphenylyl, naphthyl, anthracenyl, or hydrogen, and at least one hydrogen in the structures of formulas (5-Ar1) to (5-Ar5) may be substituted with phenyl, biphenylyl, naphthyl, anthracenyl, phenanthrenyl, methyl, ethyl, propyl, or butyl.

[0305] 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-.

[0306] 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.

[0307] The compound represented by formula (5-H) more preferably has R 1 , R 2 , R 4 , R 5 , R 7 , R 8 , R 9 , R 10 , R 12 , R 13 , R 15 and R 16 being hydrogen. In this case, R 3 , R 6 , R 11 and R 14At least one (preferably one or two, more preferably one) of them 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-; the positions other than the at least one (i.e., the positions other than those substituted by the monovalent group having the structure) are hydrogen, phenyl, biphenylyl, naphthyl, anthracenyl, methyl, ethyl, propyl, or butyl, and at least one hydrogen in these may be substituted by phenyl, biphenylyl, naphthyl, anthracenyl, methyl, ethyl, propyl, or butyl.

[0308] Also, R in formula (5-H) 2 , R 3 , R 6 , R 7 , R 10 , R 11 , R 14 and R 15 When a monovalent group having a structure represented by formula (5-Ar1) to formula (5-Ar5) is selected as R 1 to R 16 in formula (5-H), at least one hydrogen in the structure may be bonded to any one of R

[0309] More specific examples of the dibenzocrisene compound as the host of the present invention include compounds represented by the following structural formulas. Note that "tBu" represents t-butyl.

Chemical formula

[0310]

Chemical formula

[0311] The above-mentioned luminescent layer materials (host materials and dopant materials) can also be used as luminescent 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.

[0312] The light-emitting layer in the organic electroluminescent device 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. The polycyclic aromatic compound of the present invention is also preferably used as an emitting dopant. As the assisting dopant (compound), a thermally activated delayed phosphor can be used.

[0313] In the following description, an organic electroluminescent device using a thermally activated delayed phosphor as an assisting dopant may be referred to as a "TAF device" (TADF Assisting Fluorescence device). The "host compound" in the TAF device 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.

[0314] "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 higher-order triplets in the excitation process from the excited triplet state to the 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 High-Efficiency 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 one with a fluorescence lifetime of 0.1 μsec or more. The measurement of the fluorescence lifetime can be carried out, for example, using a fluorescence lifetime measurement device (manufactured by Hamamatsu Photonics, C11367-01).

[0315] 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.

[0316] 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 denoted as 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, which is 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, which is 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, which is the second component, is E(2,T,Sh), the energy level of the ground state of the emitting dopant, which is 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, which is 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, which is 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, part of the energy is not utilized for light emission, resulting in energy waste.

[0317] 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.

[0318] 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, a 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 good at them, it is expected that the residence time of high energy will decrease and the burden on the compound will decrease.

[0319] In this embodiment, as the host compound, a known one can be used. For example, a compound 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.

[0320] The triplet excitation energy level E(1,T,Sh) determined from the shoulder on the short-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). Further, a compound having TADF activity may be used as the host compound.

[0321] As the host compound, for example, a compound represented by any of the above formulas (H1), (H2), and (H3) can be used.

[0322] <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.

[0323] 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 with a small ΔE(ST), resulting in a very fast reverse intersystem crossing rate. 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 are different between the ground state and the excited state, when the conversion from the ground state to the excited state occurs by an external stimulus, the structure then changes to the stable structure in the excited state), giving a broad emission spectrum, and thus may reduce the color purity when used as a light-emitting material.

[0324] As the 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, phenylbicarba zole, bicarba zole, tercarbazole, diphenylcarbazolylamine, tetraphenylcarbazolyl diamine, phenoxazine, dihydrophenazine, phenothiazine, dimethyldihydroacridine, diphenylamine, bis(tert-butyl)phenyl)amine, (diphenylamino)phenyl)diphenylbenzene diamine, dimethyltetraphenyldihydroacridine diamine, tetramethyl-dihydro-indenoa cridine and diphenyl-dihydrodibenzaza siline. 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, thioxanthene dioxide, dimethylanthraquinone, anthraquinone, cycloheptabipyridine, fluorenedicarbonitrile, triphenyltriazine, pyrazinedicarbonitrile, pyrimidine, phenylpyrimidine, methylpyrimidine, pyridinedicarbonitrile, dibenzoquinoxaline dicarbonitrile, 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.

[0325] 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 will be 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, tBu represents t-butyl, and the wavy line represents the bonding position.

[0326]

Chemical formula

[0327]

Chemical formula

[0328]

Chemical formula

[0329]

Chemical formula

[0330]

Chemical formula

[0331] 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]

[0332] In the above formulas (AD1), (AD2) and (AD3), each M is independently a single bond, -O-, >N-Ar or >CAr2, and is preferably a single bond, -O- or >N-Ar 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. J is a spacer structure that separates the donor part structure and the acceptor part structure, and each is independently an arylene having 6 to 18 carbon atoms, and an arylene having 6 to 12 carbon atoms is preferable from the viewpoint of the magnitude of the conjugation oozing from the donor part structure and the acceptor part structure. More specifically, phenylene, methylphenylene and dimethylphenylene can be mentioned. Each Q is independently =C(-H)- or =N-, and is preferably =N- 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. Each 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, and 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 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, more preferably hydrogen, phenyl, tolyl, xylyl, mesityl, biphenyl, pyridyl, bipyridyl, triazyl, 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) or less, and is preferably an integer of 4 to (6 - m) from the viewpoint of steric hindrance. Further, at least one hydrogen in the compound represented by the above formulas may be substituted with halogen or deuterium.

[0333] 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.

[0334] 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 formula (DAD1) and formula (DAD2), D 1 , D 2 and D 3 each independently represent a donor group. As the donor group, the above donor 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, the compound represented by formula (DAD2) is obtained. The n D 1 may be the same or different, and the n L 1 may be the same or different. Preferred specific examples of the compounds represented by formula (DAD1) and formula (DAD2) include 2PXZ-TAZ and the following compounds, but the second component that can be employed in the present invention is not limited to these compounds.

[0335]

Chemical formula

[0336] 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.

[0337] The amount of the host compound used varies depending on the type of the host compound, and it may be determined according to the characteristics of the host compound. The standard 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, for example, it is preferable in terms of efficient charge transport and efficient energy transfer to the dopant.

[0338] The amount of the assisting dopant (thermally activated delayed phosphor) used varies depending on the type of the assisting dopant, and it may be determined according to the characteristics of the assisting dopant. The standard 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, for example, it is preferable in terms of efficiently transferring energy to the emitting dopant.

[0339] The amount of the emitting dopant (a compound having a boron atom) varies depending on the type of the emitting dopant, and it may be determined according to the characteristics of the emitting dopant. The standard amount of the emitting dopant 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.

[0340] In terms of preventing the concentration quenching phenomenon, it is preferable that the amount of the emitting dopant is low. In terms of the efficiency of the thermally activated delayed fluorescence mechanism, it is preferable that the amount of the assisting dopant 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 is lower than the amount of the assisting dopant.

[0341] <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, and 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. For example, a thickness of 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.

[0342] <2-1-4. Anode in Organic Electroluminescent Element> The anode 102 serves to inject holes into the light-emitting layer 105. When either one of the hole injection layer 103 and the transport layer 104 is provided between the anode 102 and the light-emitting layer 105, holes are injected into the light-emitting layer 105 through these.

[0343] 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 substances used as anodes of organic EL elements.

[0344] 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 preferably 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 / square or less can function as an element electrode, but currently substrates with a resistance of about 10 Ω / square can also be supplied. Therefore, it is particularly desirable to use low-resistance products with a resistance of, for example, 100 to 5 Ω / square, preferably 50 to 5 Ω / square. The thickness of ITO can be arbitrarily selected according to the resistance value, but it is usually used in the range of 50 to 300 nm.

[0345] <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.

[0346] As a hole injection / transport material, it is necessary to efficiently inject / 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 less likely to occur during production and use.

[0347] As materials 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 that have been conventionally used as hole charge transport materials, p-type semiconductors, and known compounds used for the hole injection layer and the hole transport layer of an organic EL element. Specific examples thereof include carbazole derivatives (such as 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 and 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, polycarbonates, styrene derivatives, polyvinylcarbazole, and polysilane having the above monomers in the side chain are preferable, but any compound that can form a thin film necessary for the production of the light-emitting element, can inject holes from the anode, and can further transport holes is not particularly limited.

[0348] 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.

[0349] <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.

[0350] <2-1-7. 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 through 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 kinds of electron transport / injection materials, or by a mixture of an electron transport / injection material and a polymer binder.

[0351] 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 be high and that the injected electrons be efficiently transported. For this purpose, it is preferable that the material has a large electron affinity, a large electron mobility, excellent stability, and is less likely to generate trap impurities during manufacturing and use. However, when considering the transport balance between holes and electrons, if the layer mainly serves to efficiently prevent 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.

[0352] As the material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107, it can be arbitrarily selected and used from compounds that have been conventionally used as electron transfer compounds in photoconductive materials and known compounds used in the electron injection layer and electron transport layer of organic EL elements.

[0353] As the material 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 the metal complex 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.

[0354] 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, arylnitrile derivatives, indole derivatives, phosphine oxide derivatives, bisstyryl derivatives, silole derivatives, and azoline derivatives, etc.

[0355] 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.

[0356] The materials described above can be used alone or can be mixed with different materials for use.

[0357] 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 preferable.

[0358] 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.

[0359] 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 this reducing substance, various substances can be used as long as they have a certain reducing property. 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.

[0360] Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (2.28 eV), Rb (2.16 eV) or Cs (1.95 eV), and alkaline earth metals such as Ca (2.9 eV), Sr (2.0 - 2.5 eV) or Ba (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 the electron injection layer, improvement in the emission luminance and extension of the lifetime in the organic EL element can be achieved. Further, as a reducing substance with a work function of 2.9 eV or less, a combination of two or more of these alkali metals is also preferred, and in particular, a combination containing Cs, for example, a combination of Cs and Na, Cs and K, Cs and Rb, or a combination of Cs, Na and K is preferred. By containing Cs, the reducing ability can be efficiently exhibited, and by adding it to the material forming the electron transport layer or the electron injection layer, improvement in the emission luminance and extension of the lifetime in the organic EL element can be achieved.

[0361] <2-1-8. Cathode in Organic Electroluminescent Element> 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.

[0362] 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 material as that 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 an alloy containing these low work function metals is effective. However, these low work function metals are generally 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.

[0363] Furthermore, for electrode protection, it is possible to laminate 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. 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.

[0364] <2-1-9. 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 independently. 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.

[0365] <2-1-10. Fabrication Method of Organic Electroluminescent Element> Each layer constituting the organic EL element can be formed by making the material for each layer into a thin film by methods 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, coating method, etc. There is no particular limitation on the film thickness of each layer formed in this way, 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, etc. 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 appropriately in the range of boat heating temperature +50 to +400 °C, vacuum degree 10 -6 ~10 -3 Pa, deposition rate 0.01 to 50 nm / second, substrate temperature -150 to +300 °C, and film thickness 2 nm to 5 μm.

[0366] 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 form 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 manufacture of the above-described organic EL element, it is also possible to manufacture in the reverse order of manufacture, that is, in the order of cathode, electron injection layer, electron transport layer, light-emitting layer, hole transport layer, hole injection layer, and anode.

[0367] When a DC voltage is applied to the organic EL element thus obtained, it may be applied with the anode as the + and the cathode as the - 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. The waveform of the alternating current to be applied may be arbitrary.

[0368] <2-1-11. 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.

[0369] 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 any one of matrix and segment methods. Note that the matrix display and the segment display may coexist in the same panel.

[0370] In the 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 on 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 and displayed. 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.

[0371] 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 on digital clocks and thermometers, operation state display on audio devices and electromagnetic cookers, and panel display of automobiles, etc. can be cited.

[0372] Examples of the lighting device include lighting devices such as indoor lighting, and backlights of 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, clocks, audio devices, automotive panels, display boards, and signs. 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.

[0373] <2-2. Other Organic Devices> 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, in addition to the above-described organic electroluminescent element.

[0374] 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.

[0375] 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 driving switching element for a liquid crystal display or an organic electroluminescence display using an active matrix driving method and the like.

[0376] 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, the p-type semiconductor layer, the n-type semiconductor layer, and the 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. In addition to the above, 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, and the like. Known materials used for the organic thin film solar cell can be appropriately selected and combined for use in the organic thin film solar cell.

[0377] <3. Wavelength conversion material> The polycyclic aromatic compound of the present invention can be used as a wavelength conversion material. Currently, the technology of multi-color conversion by color conversion methods is being actively studied for application to liquid crystal displays, organic EL displays, lighting, etc. Color conversion means converting the light emitted from a light emitter to light of a longer wavelength. For example, it represents converting ultraviolet light or blue light to 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 produce a full-color display. Also, if there is no liquid crystal driving part, it can be used as a white light source as it is and can be applied as a white light source for, for example, LED lighting. Further, by using a blue organic EL element as a light source and combining it with a wavelength conversion film that converts blue light to green light and red light, it becomes possible to produce a full-color organic EL display without using a metal mask. Furthermore, by using a blue micro LED as a light source and combining it with a wavelength conversion film that converts blue light to green light and red light, it becomes possible to produce a low-cost full-color micro LED display.

[0378] 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 of 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 substituents of the polycyclic aromatic compound of the present invention, a 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.

[0379] 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 composition for forming a light-emitting layer.

[0380] 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

[0381] Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited thereto.

[0382] Synthesis Example (1): Synthesis of Compound (1-1)

Chemical Formula

[0383] Under a nitrogen atmosphere, intermediate (X-1) (50.0 g), 1-t-butyl-3,4,5-trichlorobenzene (32.0 g), dichlorobis(di-t-butyl(4-dimethylaminophenyl)phosphino)palladium (Pd-132) (0.909 g) as a palladium catalyst, sodium t-butoxide (NaOtBu, 18.5 g) and toluene (500 ml) were placed in a flask and heated at 120 °C for 5 hours. After completion of the reaction, water and ethyl acetate were added to the reaction solution and stirred, and then the organic layer was separated and washed with water. Thereafter, the crude product obtained by concentrating the organic layer was purified by a silica gel short path column (eluent: heptane) to obtain 49.3 g of intermediate (X-2).

Chemical formula

[0384] Under a nitrogen atmosphere, intermediate (X-2) (30.0 g), intermediate (X-3) (26.6 g), Pd-132 (0.719 g) as a palladium catalyst, NaOtBu (7.32 g) and toluene (300 ml) were placed in a flask and heated at 120 °C for 3 hours. After completion of the reaction, water and ethyl acetate were added to the reaction solution and stirred, and then the organic layer was separated and washed with water. Thereafter, the crude product obtained by concentrating the organic layer was purified by a silica gel short path column (eluent: toluene / heptane = 1 / 9 (volume ratio)) to obtain 43.8 g of intermediate (X-4).

Chemical formula

[0385] To a flask containing intermediate (X-4) (21.5 g) and tert-butylbenzene (tBu-benzene, 215 ml), 1.60 M tert-butyllithium pentane solution (tBuLi, 25.0 ml) was added at 0 °C under a nitrogen atmosphere. After completion of the dropwise addition, the temperature was raised to 70 °C and stirred for 0.5 hour, and then the components with lower boiling points than tert-butylbenzene were distilled off under reduced pressure. The mixture was cooled to -50 °C, boron tribromide (10.0 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 (EtNiPr2, 5.15 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 2.05 g of compound (1-1). [Chemical formula]

[0386] The structure of the compound obtained by NMR measurement was confirmed. 1 1H-NMR (CDCl3): δ = 8.96 - 8.86 (m, 2H), 7.66 - 7.55 (m, 2H), 7.40 - 7.24 (m, 3H), 7.16 - 7.06 (m, 1H), 6.95 (d, 1H), 6.72 - 6.64 (m, 2H), 6.42 (d, 1H), 6.20 - 6.12 (m, 2H), 1.82 - 1.61 (m, 18H), 1.56 - 1.38 (m, 18H), 1.34 (s, 9H), 1.29 - 1.22 (m, 15H), 1.14 - 1.04 (m, 9H), 0.93 - 0.87 (m, 12H).

[0387] By appropriately changing the starting compounds, other compounds of the present invention can be synthesized by a method according to the above-described synthesis example.

[0388] [Evaluation method of basic physical properties] [Preparation of samples] When evaluating the absorption characteristics and luminescence characteristics (fluorescence and phosphorescence) of a compound to be evaluated, there are cases where the compound to be evaluated is dissolved in a solvent and evaluated in the solvent, and cases where it is evaluated in a thin film state. Furthermore, when evaluating in a thin film state, depending on the mode of use of the compound to be evaluated in an organic EL element, there are cases where only the compound to be evaluated is formed into a thin film and evaluated, and cases where the compound to be evaluated is dispersed in a suitable matrix material and formed into a thin film for evaluation. Here, a thin film obtained by depositing only the compound to be evaluated is referred to as a "single film", and a thin film obtained by applying and drying a coating solution containing the compound to be evaluated and a matrix material is referred to as a "coated film".

[0389] As the matrix material, commercially available PMMA (polymethyl methacrylate) etc. can be used. In this example, after dissolving PMMA and the compound to be evaluated in toluene, a thin film is formed on a transparent support substrate made of quartz (10 mm × 10 mm) by the spin coating method to prepare a sample.

[0390] Also, a thin film sample when the matrix material is a host compound is prepared as follows. A transparent support substrate made of quartz (10 mm × 10 mm × 1.0 mm) is fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Choshu Sangyo Co., Ltd.). After attaching a molybdenum vapor deposition boat containing the host compound and a molybdenum vapor deposition boat containing the dopant material, the vacuum chamber is evacuated to 5×10 -4 Pa. Next, the vapor deposition boat containing the host compound and the vapor deposition boat containing the dopant material are heated simultaneously, and the host compound and the dopant material are co-evaporated to an appropriate film thickness to form a mixed thin film (sample) of the host compound and the dopant material. Here, the vapor deposition rate is controlled according to the set mass ratio of the host compound and the dopant material.

[0391] <Evaluation of Absorption Characteristics and Luminescence Characteristics> The absorption spectrum of the sample is measured using an ultraviolet-visible-near-infrared spectrophotometer (Shimadzu Corporation, UV-2600). Also, the fluorescence spectrum or phosphorescence spectrum of the sample is measured using a spectrofluorometer (manufactured by Hitachi High-Tech Corporation, F-7000).

[0392] For the measurement of the fluorescence spectrum, excitation is carried out at an appropriate excitation wavelength at room temperature, and photoluminescence is measured. For the measurement of the phosphorescence spectrum, using the attached cooling unit, the measurement is carried out with the sample immersed in liquid nitrogen (temperature 77 K). To observe the phosphorescence spectrum, an optical chopper was used to adjust the delay time from the excitation light irradiation to the start of the measurement. The sample is excited at an appropriate excitation wavelength and photoluminescence is measured.

[0393] Also, the fluorescence quantum yield (PLQY) is measured using an absolute PL quantum yield measurement device (manufactured by Hamamatsu Photonics K.K., C9920-02G).

[0394] Next, the basic physical property evaluation of the polycyclic aromatic compound of the present invention will be described.

[0395] <Evaluation of fluorescence lifetime (delayed fluorescence)> The fluorescence lifetime was measured at 300 K using a fluorescence lifetime measurement device (manufactured by Hamamatsu Photonics K.K., C11367-01). Specifically, fast and slow emission components of the fluorescence lifetime were observed at the maximum emission wavelength measured at an appropriate excitation wavelength. In the measurement of the fluorescence lifetime at room temperature of a general organic EL material that emits fluorescence, due to the deactivation of the triplet component by heat, a slow emission component involving the triplet component derived from phosphorescence is hardly observed. When a slow emission component is observed in the compound to be evaluated, it indicates that the triplet energy with a long excitation lifetime has moved to the singlet energy by thermal activation and is observed as delayed fluorescence.

[0396] <Calculation of energy gap (Eg)> It is calculated as Eg = 1240 / A from the long-wavelength end A (nm) of the absorption spectrum obtained by the above-described method.

[0397] <Measurement of ionization potential (Ip)> A commercially available vapor deposition apparatus (manufactured by Choshu Sangyo Co., Ltd.) was used to fix a transparent support substrate (28 mm × 26 mm × 0.7 mm) vapor-deposited with ITO (indium tin oxide) to the substrate holder. After mounting a molybdenum vapor deposition boat containing the target compound, the vacuum chamber was evacuated to 5×10 -4 Pa. Next, the vapor deposition boat was heated to evaporate the target compound and form a neat film of the target compound.

[0398] Using the obtained neat film as a sample, the ionization potential of the target compound was measured using a photoelectron spectrometer (Sumitomo Heavy Industries, Ltd. PYS-201).

[0399] <Calculation of electron affinity (Ea)> The electron affinity can be estimated from the difference between the ionization potential measured by the above method and the energy gap calculated by the above method.

[0400] <Measurement of singlet excitation energy level E(S,Sh) and triplet excitation energy level E(T,Sh)> For the neat film of the target compound formed on a glass substrate, at 77 K, the fluorescence spectrum was observed with excitation light at the peak on the long-wavelength side so that the fluorescence peaks of the absorption spectrum did not overlap, and the singlet excitation energy level E(S,Sh) was determined from the shoulder on the short-wavelength side of the peak of the fluorescence spectrum. Also, for the neat film of the target compound formed on a glass substrate, at 77 K, the phosphorescence spectrum was observed with excitation light at the peak on the long-wavelength side so that the fluorescence peaks of the absorption spectrum did not overlap, and the triplet excitation energy level E(T,Sh) was determined from the shoulder on the short-wavelength side of the peak of the phosphorescence spectrum.

[0401] <Evaluation of organic EL element> As described above, the compound of the present invention has an appropriate energy gap (Eg), high triplet excitation energy (E T ) and a small ΔEST, and thus can be expected to be applied, for example, to a light-emitting layer and a charge transport layer, and particularly to a light-emitting layer.

[0402] <Evaluation items and evaluation methods> 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.

[0403] The quantum efficiency of the light-emitting element has internal quantum efficiency and external quantum efficiency. The internal quantum efficiency indicates the ratio at which the external energy injected as electrons (or holes) into the light-emitting layer of the light-emitting element 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 element. Since some of the photons generated in the light-emitting layer are absorbed or continuously reflected inside the light-emitting element and are not emitted to the outside of the light-emitting element, the external quantum efficiency is lower than the internal quantum efficiency.

[0404] The measurement methods for spectral radiance (emission spectrum) and external quantum efficiency are as follows. By applying a voltage using a voltage / current generator R6144 manufactured by Advantest Corporation, the element was made to emit light. Using a spectral radiance meter SR-3AR manufactured by TOPCON Corporation, the spectral radiance in the visible light region was measured from the perpendicular direction with respect 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 element. Using the value obtained by dividing the applied current value by the elementary charge as the number of carriers injected into the element, the value obtained by dividing the total number of photons emitted from the element by the number of carriers injected into the element is the external quantum efficiency. Also, the full width at half maximum of the emission spectrum is obtained as the width between the wavelengths above and below at which the intensity becomes 50% centered on the maximum emission wavelength.

[0405] Next, the fabrication and evaluation of the organic EL element using the polycyclic aromatic compound of the present invention will be described.

[0406] <Configuration of Organic EL Element> An organic EL element was manufactured using the polycyclic aromatic compound of the present invention.

[0407] [Element Structure A] The material compositions of each layer in the organic EL elements of Example 1 and Comparative Examples 1 to 4 are shown in Table 1 below.

Table 1

[0408] In Table 1, "HI" is N 4 ,N 4’ -diphenyl-N 4 ,N 4’ -bis(9-phenyl-9H-carbazol-3-yl)-[1,1'-biphenyl]-4,4'-diamine, "HAT-CN" is 1,4,5,8,9,12-hexaazatriphenylene hexacarbonitrile, "HT-1" is N-([1,1'-biphenyl]-4-yl-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluorene-2-amine, "HT-2" is N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)-[1,1':4',1"-terphenyl]-4-amine, "BH" is 2-(10-phenylanthracen-9-yl)dibenzo[b,d]furan, "ET-1" is 9,9'-[(5-(6-(1,1'-biphenyl)-4-yl)-2-phenylpyrimidin-4-yl)-1,3-phenylene]bis(9H-carbazole), and "ET-2" is 4-(6-(10-phenylanthracen-9-yl)naphthalen-2-yl)pyridine. "Liq", Comparative Compound (1) (compound described in International Publication No. 2015 / 102118), Comparative Compound (2) (compound described in International Publication No. 2019 / 132028), Comparative Compound (3) (compound described in International Publication No. 2020 / 017931), and Comparative Compound (4) (compound described in International Publication No. 2020 / 218079) are shown below with their chemical structures.

[0409]

Chemical Structure

[0410] [Chem.]

[0411] (Example 1) A glass substrate (manufactured by Opto Science Co., Ltd.) with dimensions of 26 mm × 28 mm × 0.7 mm, on which ITO formed to a thickness of 180 nm by sputtering was polished to 150 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 HI, HAT-CN, HT-1, HT-2, BH, Compound (1-1), ET-1, and ET-2 respectively, and aluminum nitride vapor deposition boats containing Liq, LiF, and aluminum respectively were installed.

[0412] The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was evacuated to 5×10 -4 Pa, and first, HI was heated and vapor-deposited to a film thickness of 40 nm. Next, HAT-CN was heated and vapor-deposited to a film thickness of 5 nm. Next, HT-1 was heated and vapor-deposited to a film thickness of 45 nm. Next, HT-2 was heated and vapor-deposited to a film thickness of 10 nm to form a hole layer composed of four layers. Next, BH and Compound (1-1) were simultaneously heated and vapor-deposited to a film thickness of 25 nm to form a light-emitting layer. The deposition rate was adjusted so that the mass ratio of BH to Compound (1-1) was approximately 97 to 3. Furthermore, ET-1 was heated and vapor-deposited to a film thickness of 5 nm. Next, ET-2 and Liq were simultaneously heated and vapor-deposited to a film thickness of 25 nm to form an electron layer composed of two layers. The deposition rate was adjusted so that the mass ratio of ET-2 to Liq was approximately 50 to 50. 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 film thickness of 1 nm, and then aluminum was heated and vapor-deposited to a film thickness of 100 nm to form a cathode, obtaining an organic EL element.

[0413] (Comparative Examples 1 - 4) An organic EL device of Comparative Examples 1 to 4 was obtained in the same manner as in Example 1, except that Comparative Compound (1), Comparative Compound (2), Comparative Compound (3), and Comparative Compound (4) were used instead of Compound (1-1).

[0414] <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, for example, values at the time of emission at 1000 cd / m 2 can be used.

[0415] 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 these 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.

[0416] The measurement methods for spectral radiant luminance (emission spectrum) and external quantum efficiency are as follows. Using a voltage / current generator R6144 manufactured by Advantest Corporation, a voltage at which the luminance of the device becomes 1000 cd / m 2 is applied to cause the device to emit light. Using a spectral radiant luminance meter SR-3AR manufactured by TOPCON Corporation, the spectral radiant luminance in the visible light region is measured from a direction perpendicular to the light-emitting surface. Assuming that the light-emitting surface is a perfect diffuser surface, the value obtained by dividing the measured value of the spectral radiant luminance 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 is integrated over the entire observed wavelength region to obtain the total number of photons emitted from the device. Using the value obtained by dividing the applied current value by the elementary charge as the number of carriers injected into 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 is the external quantum efficiency. Also, the full width at half maximum of the emission spectrum is determined as the width between the upper and lower wavelengths at which the intensity becomes 50% centered on the maximum emission wavelength.

[0417] For the organic EL elements of Example 1 and Comparative Examples 1 to 4, a DC voltage was applied with the ITO electrode as the anode and the LiF / aluminum electrode as the cathode, and the characteristics during light emission were measured at 1000 cd / m 2 The results are shown in Table 2.

[0418]

Table 2

Industrial Applicability

[0419] The polycyclic aromatic compound of the present invention is useful as a material for organic devices, particularly as a material for a light-emitting layer for forming a light-emitting layer of an organic electroluminescent element. By using the polycyclic aromatic compound of the present invention as a dopant for the light-emitting layer, an organic electroluminescent element with low voltage and high-efficiency light emission can be obtained.

Explanation of Reference Numerals

[0420] 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 the following formula (2); 【Chemical 1】 In formula (2), Z in the a-ring, b-ring, and c-ring is each independently C-R 11 wherein said C-R 11 and R 11 are each independently hydrogen, alkyl, or cycloalkyl, Y 1 is B, X 1 and X 2 is each independently >N-R, wherein R of the >N-R is an aryl or a monovalent group represented by formula (G-2), and at least one hydrogen in these may be further substituted with alkyl or cycloalkyl, provided that at least one of 1 X 2 is >N-R in which R is a monovalent group represented by formula (G-2). In formula (G-2), Z in the G-a ring and the G-b ring G is each independently C-R 12 and the R of the C-R 12 is each independently hydrogen, alkyl, or cycloalkyl. 12 ​ X 3 and X 4 either one of them is > O, and the other is > O, > N-R, > C(-R) 2 , or > S, or either one of them is > S, and the other is > N-R, > C(-R) 2 , or > S, where R in > N-R is aryl, and at least one hydrogen in this aryl may be substituted with alkyl or cycloalkyl, and R in > C(-R) 2 are each independently hydrogen or alkyl L is a single bond or phenylene, and at least one hydrogen of the phenylene may be substituted with alkyl or cycloalkyl; In formula (G-2), one bond of L is linked to any Z G in the (G-a) ring at the carbon atom thereof, and the other bond is linked to N of >N-R, At least one of the benzene rings which are the a-ring, b-ring and c-ring and the aryl ring of R which is >N-R where X1 or X2 may be condensed with at least one cycloalkane, and at least one hydrogen in the cycloalkane may be substituted; At least one hydrogen in the structure represented by formula (2) may be substituted with deuterium.

2. The polycyclic aromatic compound according to Claim 1, wherein at least one of the benzene rings which are the a-ring, b-ring and c-ring and the aryl ring of R which is >N-R where X1 or X2 is condensed with at least one cycloalkane, and at least one hydrogen in the cycloalkane may be substituted.

3. The polycyclic aromatic compound according to Claim 1 or 2, wherein L is a single bond.

4. The polycyclic aromatic compound according to Claim 1, represented by the following formula. [Chemical 2]

5. A material for an organic device, containing the polycyclic aromatic compound according to any one of Claims 1 to 4.

6. An organic electroluminescent element 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 4.

7. The organic electroluminescent element according to Claim 6, wherein the light-emitting layer contains a host and the polycyclic aromatic compound as a dopant.

8. The organic electroluminescent element according to Claim 7, wherein the host is an anthracene compound, a fluorene compound, or a dibenzocrisene compound.

9. A display device or a lighting device including the organic electroluminescent element according to any one of Claims 6 to 8.

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