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

Abstract

Provided are: a polycyclic aromatic compound which is useful as a material for an organic device such as an organic electroluminescent element; a material for an organic device; an organic electroluminescent element; a display device; a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1); ring A to ring E are substituted or unsubstituted aryl rings or heteroaryl rings, at least one of ring A to ring C contains at least one group represented by formula (G) as a substituent, at least one Ar in the structure is a monovalent group represented by formula (Ar), Z is-C (-RZ) = or-N =, Rg1 to Rg4, RZ is hydrogen or a substituent, and Rg1 to Rg4 are hydrogen or a substituent. The aryl ring or heteroaryl ring in the structure may be condensed from cycloalkanes, and at least one hydrogen in the structure may be substituted with deuterium. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a polycyclic aromatic compound. In particular, the present invention relates to a polycyclic aromatic compound containing nitrogen and boron. The present invention also relates to an organic device material, an organic electroluminescent element, a display device and a lighting device containing the polycyclic aromatic compound. Background Art

[0002] In the past, display devices using light-emitting elements that perform electroluminescence have been studied in various ways because they can achieve power saving or thinning, and organic electroluminescent elements containing organic materials have been actively studied because they can be easily lightweight or large-scaled. In particular, the development of organic materials having luminous properties such as blue, which is one of the three primary colors of light, and the development of organic materials having charge transport capabilities including holes, electrons, etc. (having the possibility of becoming semiconductors or superconductors) have been actively studied so far, regardless of whether they are polymer compounds or low molecular weight compounds.

[0003] An organic electroluminescent element has a structure including a pair of electrodes including an anode and a cathode, and one or more layers disposed between the pair of electrodes and including an organic compound. The layers including the organic compound include a light-emitting layer, a charge transport / injection layer for transporting or injecting charges such as holes and electrons, and various organic materials suitable for these layers have been developed.

[0004] Among them, Patent Documents 1 to 4 disclose that polycyclic aromatic compounds containing boron are effectively used as materials for organic electroluminescent elements and the like.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] [Patent Document 1] International Publication No. 2015 / 102118

[0008] [Patent Document 2] International Publication No. 2020 / 022770

[0009] [Patent Document 3] International Publication No. 2020 / 200884

[0010] [Patent Document 4] Korean Patent Publication No. 10-2022-0069866 Summary of the invention

[0011] [Problems to be solved by the invention]

[0012] As described above, various materials have been developed as materials used in organic electroluminescence (EL) elements. However, in order to increase the selection of materials for organic EL elements, it is desired to develop a material including a novel compound.

[0013] An object of the present invention is to provide a novel compound which can be effectively used as a material for an organic device such as an organic EL element.

[0014] [Technical means to solve the problem]

[0015] The present inventors have made great efforts to solve the above problems and have successfully produced novel polycyclic aromatic compounds with better luminescent properties among polycyclic aromatic compounds having structures similar to the compounds described in Patent Documents 1 to 4. In addition, it was found that an excellent organic EL element can be obtained by configuring an organic EL element with a layer containing the polycyclic aromatic compound between a pair of electrodes, thereby completing the present invention. That is, the present invention provides the following polycyclic aromatic compounds, and further provides materials for organic devices containing the following polycyclic aromatic compounds.

[0016] Specifically, the present invention has the following structures.

[0017] <1> A polycyclic aromatic compound having a structure consisting of one or two or more structural units represented by formula (1);

[0018] [Chemistry 1]

[0019]

[0020] In formula (1),

[0021] Ring A, Ring B and Ring C are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,

[0022] wherein at least one selected from the group consisting of the A ring, the B ring and the C ring in the structure comprises at least one group represented by formula (G) as a substituent,

[0023] [Chemistry 2]

[0024]

[0025] In formula (G),

[0026] The D ring and the E ring are each independently a substituted or unsubstituted aryl ring, a substituted or unsubstituted heteroaryl ring, wherein any one of them may be a substituted or unsubstituted cycloalkane ring,

[0027] # indicates the bonding position to the aryl ring or heteroaryl ring in the A ring, B ring or C ring,

[0028] Ar is each independently a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group,

[0029] Wherein, at least one of Ar in the structure is a monovalent group represented by formula (Ar),

[0030] [Chemistry 3]

[0031]

[0032] In formula (Ar),

[0033] * indicates the bonding position to the nitrogen atom,

[0034] R g1 ~R g4 are each independently hydrogen or a substituent,

[0035] R g1 ~R g4 The two adjacent groups in the group may be bonded to each other and, together with the benzene ring to which they are bonded, form a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring,

[0036] Z are each independently -C(-R Z )=or-N=,R Z are independently hydrogen or a substituent, at least one set of adjacent -C(-R Z )=Z can be in R Z They are bonded to each other to form a ring,

[0037] Ar other than the monovalent group represented by formula (Ar) may be bonded to at least one of the A ring, the B ring, and the C ring via a linking group or a single bond;

[0038] At least one of the aryl rings or heteroaryl rings in the structure may be condensed with at least one cycloalkane, the cycloalkane may have a substituent, and at least one -CH 2 - may be substituted by -O-,

[0039] In the structure, at least one hydrogen may be replaced by deuterium, and at least one nitrogen may be replaced by nitrogen-15( 15 N) substituted, at least one sulfur may be replaced by sulfur-33( 33 S), sulfur-34 ( 34 S) or sulfur-36( 36 S), at least one oxygen may be replaced by oxygen-17( 17 O) or oxygen-18 ( 18 O) substituted, at least one carbon may be substituted by carbon-13 ( 13C) substituted, at least one boron may be substituted by boron-11( 11 B) Replacement.

[0040] <2> The polycyclic aromatic compound according to <1>, wherein at least one Z is R Z -C(-R Z )=, or at least one set of adjacent ones as -C(-R Z )=Z in R Z are bonded to each other to form a ring, wherein any adjacent Z is not in R Z When the substituents R Z When the number of substituents is 4 or less except hydrogen atoms, at least two Z are R Z -C(-R Z )=.

[0041] <3> The polycyclic aromatic compound according to <2>, wherein at least one R Z is at least one substituent selected from the substituent group ZA1, and can be combined with the adjacent R Z The substituent group ZA1 may be substituted by at least one substituent selected from the substituent group ZB1;

[0042] Substituent group ZA1: aryl, heteroaryl, alkyl, cycloalkyl, arylalkyl, diarylamino, diheteroarylamino, arylheteroarylamino, triarylsilyl, diarylmonoalkylsilyl, monoaryldialkylsilyl, trialkylsilyl, monoarylmonoalkylamino, dialkylamino, diphenylphosphoryl, aryloxy, arylthio and diarylboryl;

[0043] Substituent group ZB1: aryl, heteroaryl, alkyl, cycloalkyl, cyano and halogen.

[0044] <4> The polycyclic aromatic compound according to <3>, wherein at least one R Z is at least one substituent selected from the following groups, and can be combined with the adjacent R Z Bond to form a ring:

[0045] Aryl, which may be substituted by at least one substituent selected from the substituent group ZB1;

[0046] Heteroaryl may be substituted with at least one substituent selected from the substituent group ZB1;

[0047] Cycloalkyl may be substituted by at least one substituent selected from the substituent group ZB1;

[0048] Arylalkyl may be substituted with at least one substituent selected from the substituent group ZB1;

[0049] The diarylamino group may be substituted with at least one substituent selected from the substituent group ZB1;

[0050] The diheteroarylamino group may be substituted with at least one substituent selected from the substituent group ZB1;

[0051] Arylheteroarylamino may be substituted with at least one substituent selected from the substituent group ZB1;

[0052] The triarylsilyl group may be substituted with at least one substituent selected from the substituent group ZB1;

[0053] The aryloxy group may be substituted by at least one substituent selected from the substituent group ZB1;

[0054] An arylthio group may be substituted with at least one substituent selected from the substituent group ZB1; and

[0055] The diarylboryl group may be substituted with at least one substituent selected from the substituent group ZB1.

[0056] <5> The polycyclic aromatic compound according to <4>, wherein the monovalent group represented by formula (Ar) is any one of the following.

[0057] [Chemistry 4]

[0058]

[0059] [Chemistry 5]

[0060]

[0061] [Chemistry 6]

[0062]

[0063] <6> The polycyclic aromatic compound according to <5>, which is represented by any one of the following structural formulas.

[0064] [Chemistry 7]

[0065]

[0066] [Chemistry 8]

[0067]

[0068] [Chemistry 9]

[0069]

[0070] In the formula, Me is a methyl group, tBu is a tert-butyl group, Cy is a cyclohexyl group, and Ad is a 1-adamantyl group.

[0071] <7> The polycyclic aromatic compound according to any one of <1> to <5>, wherein at least one of the A ring, the B ring, and the C ring is a substituted or unsubstituted heteroaryl ring.

[0072] <8> The polycyclic aromatic compound according to <7>, which is represented by any one of the following structural formulas.

[0073] [Chemistry 10]

[0074]

[0075] [Chemistry 11]

[0076]

[0077] [Chemistry 12]

[0078]

[0079] In the formula, Me is a methyl group, tBu is a tert-butyl group, Cy is a cyclohexyl group, and Ad is a 1-adamantyl group.

[0080] <9> An organic device material comprising the polycyclic aromatic compound according to any one of <1> to <8>.

[0081] <10> An organic electroluminescent element comprising: a pair of electrodes including an anode and a cathode; and an organic layer disposed between the pair of electrodes, the organic layer containing the polycyclic aromatic compound according to any one of <1> to <8>.

[0082] <11> The organic electroluminescent element according to <10>, wherein the organic layer is a light-emitting layer.

[0083] <12> The organic electroluminescent element according to <11>, wherein the light-emitting layer includes at least one selected from the group consisting of an auxiliary dopant and a phosphorescent material.

[0084] <13> A display device or a lighting device, comprising the organic electroluminescent element according to any one of <10> to <12>.

[0085] [Effects of the Invention]

[0086] According to the present invention, there is provided a novel polycyclic aromatic compound which is effectively used as a material for an organic device such as an organic electroluminescent element. The polycyclic aromatic compound of the present invention can be used to produce an organic device such as an organic electroluminescent element. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] Figure 1This is a schematic cross-sectional view showing an example of an organic electroluminescent element.

[0088] [Explanation of Symbols]

[0089] 100: Organic electroluminescent element

[0090] 101: Substrate

[0091] 102: Anode

[0092] 103: Hole injection layer

[0093] 104: Hole transport layer

[0094] 105: Luminous layer

[0095] 106: Electron transport layer

[0096] 107: Electron injection layer

[0097] 108: Cathode DETAILED DESCRIPTION

[0098] Hereinafter, the present invention will be described in detail. The description of the constituent elements described below is sometimes based on representative embodiments or specific examples, but the present invention is not limited to such embodiments. In addition, in this specification, the numerical range represented by "~" refers to the range including the numerical values ​​described before and after "~" as the lower limit and the upper limit. In addition, in this specification, the "hydrogen" in the description of the structural formula refers to "hydrogen atom (H)". Similarly, "carbon atom (C)" is sometimes referred to as "carbon".

[0099] In the present specification, "adjacent groups" refer to two groups respectively bonded to two adjacent atoms (two atoms directly bonded by a covalent bond) in a structural formula.

[0100] In the present specification, "Me" represents a methyl group, "Et" represents an ethyl group, "nBu" represents a normal butyl group, "tBu" represents a tertiary butyl group, "iBu" represents an isobutyl group, "secBu" represents a secondary butyl group, "nPr" represents a normal propyl group, "iPr" represents an isopropyl group, "tAm" represents a tert-amyl group, "2EH" represents a 2-ethylhexyl group, "tOct" represents a tert-octyl group, "Ph" represents a phenyl group, "Mes" represents mesityl (2,4,6-trimethylphenyl), "Ad" represents a 1-adamantyl group, "Tf" represents a trifluoromethanesulfonyl group, "TMS" represents a trimethylsilyl group, and "D" represents a deuterium group.

[0101] In this specification, an organic electroluminescent element may be referred to as an "organic EL element".

[0102] In this specification, the chemical structure or substituent is sometimes represented by the carbon number, but the carbon number when the chemical structure is substituted with a substituent, or when the substituent is further substituted with a substituent, etc., refers to the carbon number of the chemical structure or the substituent, and does not refer to the total carbon number of the chemical structure and the substituent, or the total carbon number of the substituent and the substituent. For example, the so-called "substituent B with carbon number Y substituted by substituent A with carbon number X" means that "substituent A with carbon number X" is substituted on "substituent B with carbon number Y", and the carbon number Y is not the total carbon number of substituent A and substituent B. In addition, for example, the so-called "substituent B with carbon number Y substituted by substituent A" means that "substituent A (without carbon number limitation)" is substituted on "substituent B with carbon number Y", and the carbon number Y is not the total carbon number of substituent A and substituent B.

[0103] In this specification, there are multiple structural formulas of aromatic compounds. Aromatic compounds are recorded by combining double bonds and single bonds, but in fact, due to the resonance of π electrons, there are also equivalent resonance structures such as multiple double bonds and single bonds alternately replaced for a single substance. In this specification, only one resonance structural formula is recorded for a substance, but other resonance structural formulas equivalent to organic chemistry are also included unless otherwise specified.

[0104] In addition, in this specification, "may be" may be expressed, but this has the same meaning as "has not been, or has been".

[0105] <Description of Ring and Substituent>

[0106] First, the details of the rings and substituents used in the present specification are described below.

[0107] Examples of the “aryl ring” in the present specification include an aryl ring having 6 to 30 carbon atoms, preferably an aryl ring having 6 to 16 carbon atoms, more preferably an aryl ring having 6 to 12 carbon atoms, and particularly preferably an aryl ring having 6 to 10 carbon atoms.

[0108] Specific examples of the "aryl ring" include a benzene ring that is a monocyclic ring system, a biphenyl ring that is a bicyclic ring system, a naphthalene ring and an indene ring that are a condensed bicyclic ring system, a terphenyl ring (meta-terphenyl, o-terphenyl, p-terphenyl) that is a tricyclic ring system, an acenaphthene ring, fluorene ring, phenanthren ring, anthracene ring that are a condensed tricyclic ring system, a triphenylene ring, a pyrene ring, a tetracene ring, The ring is a perylene ring, a pentacene ring, etc. of a condensed five-ring system. In addition, the fluorene ring, the benzofluorene ring, and the indene ring also include structures in which the fluorene ring, the benzofluorene ring, the cyclopentane ring, etc. are spiro-bonded. In addition, the fluorene ring, the benzofluorene ring, and the indene ring also include rings in which two of the two hydrogen atoms of the methylene group in the structure are replaced by alkyl groups such as methyl groups described later as the first substituent to form dimethylfluorene rings, dimethylbenzofluorene rings, dimethylindene rings, etc.

[0109] As the "heteroaryl ring" in the present specification, for example, a heteroaryl ring having 2 to 30 carbon atoms can be mentioned, preferably a heteroaryl ring having 2 to 25 carbon atoms, more preferably a heteroaryl ring having 2 to 20 carbon atoms, further preferably a heteroaryl ring having 2 to 15 carbon atoms, and particularly preferably a heteroaryl ring having 2 to 10 carbon atoms can be mentioned. In addition, as the "heteroaryl ring", for example, a heterocyclic ring containing 1 to 5 heteroatoms selected from oxygen, sulfur, nitrogen, boron, selenium, phosphorus, and tellurium as ring-constituting atoms other than carbon can be mentioned.

[0110] Specific examples of the "heteroaryl ring" include a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring (such as a furazan ring), a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, an isoindole ring, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a 1H-benzotriazole ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, a carbazole ring, an acridine ring, a phenoxathiol ring, a phenoxazine ring, a phenothiazine ring, a phenazine ring, a phenazasiline ring, an indolizine ring, a furan ring, a benzofuran ring, an isobenzofuran ring, a dibenzofuran ring, Thiophene ring, benzothiophene ring, dibenzothiophene ring, thianthrene ring, indolecarbazole ring, benzindolecarbazole ring, dibenzoindolecarbazole ring, naphthobenzofuran ring, dioxin ring, dihydroacridine ring, xanthene ring, thioxanthene ring, dibenzodioxin ring, dioxaborinaphthoanthracene ring (5,9-dioxa-13b-bora-13bH-naphtho[3,2,1-de]anthracene ring, etc.), benzoselenophene ring, dibenzoselenophene ring, azacarbazole ring, azadibenzothiophene ring, azadibenzofuran ring, azadibenzoselenophene ring, azatriphenylene ring, imidazoimidazole ring, indoloindole ring, benzofuranocarbazole ring, benzothiophenocarbazole ring, indenocarbazole ring and selenophenecarbazole ring, spiro[fluorene-9,9'-xanthene] ring, spirobis[siliconfluorene] ring, etc. In addition, among the dihydroacridine ring, xanthene ring and thioxanthene ring, two of the two hydrogen atoms of the methylene group in the structure are preferably substituted with an alkyl group such as a methyl group as described later as the first substituent to form a dimethyldihydroacridine ring, a dimethylxanthene ring, a dimethylthioxanthene ring, etc. In addition, bipyridine ring, phenylpyridine ring, pyridylphenyl ring as a bicyclic ring system, terpyridine ring, bipyridylphenyl ring, pyridylbiphenyl ring as a tricyclic ring system can also be listed as a "heteroaryl ring". In addition, the "heteroaryl ring" also includes a pyran ring.

[0111] In this specification, a substituent may be substituted with a further substituent. For example, a specific substituent may be described as "substituted or unsubstituted". This means that the specific substituent is substituted with at least one further substituent or is unsubstituted. In the same sense, it is sometimes referred to as "substitutable". In this specification, the specific substituent at this time may be referred to as a "first substituent" and the further substituent may be referred to as a "second substituent".

[0112] In the present specification, the substituent group Zα includes the substituents of the substituent group Z and the substituents represented by the formula (A30) described later.

[0113] In the present specification, the substituent group Z includes:

[0114] The aryl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0115] The heteroaryl group may be substituted by at least one group selected from the group consisting of aryl, heteroaryl, alkyl, cycloalkyl, cyano and halogen.

[0116] The diarylamino group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group, and the two aryl groups in the diarylamino group may be bonded to each other via a linking group.

[0117] The diheteroarylamino group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group, and the two heteroaryl groups in the diheteroarylamino group may be bonded to each other via a linking group.

[0118] The arylheteroarylamino group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group, and the aryl group and the heteroaryl group in the arylheteroarylamino group may be bonded to each other via a linking group.

[0119] The diarylboryl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group, and the two aryl groups in the diarylboryl group may be bonded via a single bond or a linking group.

[0120] The alkyl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, a cycloalkyl group, a cyano group and a halogen group,

[0121] The cycloalkyl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0122] The alkoxy group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, a cycloalkyl group, a cyano group and a halogen group,

[0123] The aryloxy group may be substituted by at least one group selected from the group consisting of aryl, heteroaryl, alkyl, cycloalkyl, cyano and halogen.

[0124] The arylthio group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group.

[0125] The alkenyl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0126] Substituted silyl, cyano and halogen.

[0127] The aryl group as the second substituent in each group of the substituent group Z may be further substituted by an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group or a halogen. Similarly, the heteroaryl group as the second substituent may be substituted by an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group or a halogen.

[0128] In the present specification, when referred to as a "substituent", the type of the substituent is not particularly limited, and unless otherwise specified, any substituent selected from the substituent group Z may be used. For example, when a "substituted or unsubstituted" group is substituted, the group may be substituted with at least one group selected from the substituent group Z.

[0129] In the present specification, the "aryl group" is, for example, an aryl group having 6 to 30 carbon atoms, and preferably an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aryl group having 6 to 10 carbon atoms.

[0130] Specific examples of the "aryl group" include a monovalent group obtained by removing one hydrogen atom from the above-mentioned "aryl ring". For example, it is a phenyl group which is a monocyclic ring, a biphenyl group (2-biphenyl, 3-biphenyl, or 4-biphenyl) which is a bicyclic ring, a naphthyl group (1-naphthyl or 2-naphthyl) which is a condensed bicyclic ring, a terphenyl group (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl-5'-yl, o-terphenyl-3'-yl, o-terphenyl-4'-yl, p-terphenyl-2'-yl, m-terphenyl-2-yl, m-terphenyl-3-yl, m-terphenyl-4-yl, o-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, or p-terphenyl-4-yl) which is a tricyclic ring, a condensed tricyclic acenaphthene group (1-, 3-, 4-, or 5- The invention also includes the following: a 1-, 2-, 3-, 4-, or 9-) group, a phenanthren-(1-, 2-, 3-, 4-, or 9-) group, a tetraphenyl group (5'-phenyl-m-terphenyl-2-yl, 5'-phenyl-m-terphenyl-3-yl, 5'-phenyl-m-terphenyl-4-yl, or m-quaterphenyl group) having a tetracyclic ring system, a triphenylene-(1-, 2-, or 4-) group, a pyrene-(1-, 2-, or 4-) group, or a tetracene-(1-, 2-, or 5-) group having a condensed tetracyclic ring system, or a perylene-(1-, 2-, or 3-) group, or a pentacene-(1-, 2-, 5-, or 6-) group having a condensed pentacyclic ring system. In addition, a monovalent group of spirofluorene and the like can be mentioned.

[0131] In addition, the aryl group serving as the second substituent also includes a structure in which the aryl group is substituted by at least one group selected from the group consisting of aryl groups such as phenyl (specific examples are the groups described above), alkyl groups such as methyl (specific examples are the groups described later), and cycloalkyl groups such as cyclohexyl or adamantyl (specific examples are the groups described later).

[0132] As an example thereof, there can be mentioned a group in which the 9-position of the fluorenyl group as the second substituent is substituted with an aryl group such as a phenyl group, an alkyl group such as a methyl group, or a cycloalkyl group such as a cyclohexyl group or an adamantyl group.

[0133] The “arylene group” is, for example, an arylene group having 6 to 30 carbon atoms, and preferably an arylene group having 6 to 20 carbon atoms, an arylene group having 6 to 16 carbon atoms, an arylene group having 6 to 12 carbon atoms, or an arylene group having 6 to 10 carbon atoms.

[0134] Specific examples of the "arylene group" include a divalent group obtained by removing one hydrogen atom from the above-mentioned "aryl group" (monovalent group).

[0135] The “heteroaryl group” is, for example, a heteroaryl group having 2 to 30 carbon atoms, preferably a heteroaryl group having 2 to 25 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a heteroaryl group having 2 to 15 carbon atoms, or a heteroaryl group having 2 to 10 carbon atoms. The “heteroaryl group” contains, in addition to carbon atoms, one or more, preferably one to five heteroatoms selected from oxygen, sulfur, and nitrogen as ring-constituting atoms.

[0136] Specific examples of "heteroaryl" include monovalent groups formed by removing one hydrogen from the "heteroaryl ring". Examples include pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, indolyl, isoindolyl, 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, phenanthrolinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiol, phenoxazinyl, phenanthrolinyl, phenanthroline ... Thiazinyl, phenazinyl, phenazasilinyl, indolizinyl, furanyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, naphthobenzofuranyl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, naphthobenzothienyl, a monovalent group of a benzophospholine oxide ring, a monovalent group of a dibenzophospholine oxide ring, furazanyl, thianthrenyl, indolecarbazolyl, benzindolecarbazolyl, dibenzoindolecarbazolyl, imidazolinyl, or oxazolinyl, etc. In addition, a monovalent group of spiro[fluorene-9,9'-xanthene], a monovalent group of spirobis[silafluorene], and a monovalent group of benzoselenophene can be mentioned.

[0137] In addition, the heteroaryl group as the second substituent also includes a structure in which the heteroaryl group is substituted by at least one group selected from the group consisting of aryl groups such as phenyl (specific examples are the groups described above), alkyl groups such as methyl (specific examples are the groups described later), and cycloalkyl groups such as cyclohexyl or adamantyl (specific examples are the groups described later).

[0138] As an example, the 9-position of the carbazolyl group as the second substituent is substituted by an aryl group such as a phenyl group, an alkyl group such as a methyl group, or a cycloalkyl group such as a cyclohexyl group or an adamantyl group. In addition, a nitrogen-containing heteroaryl group such as a pyridyl group, a pyrimidyl group, a triazine group, a carbazolyl group, etc., which is further substituted by a phenyl group or a biphenyl group, is also included in the heteroaryl group as the second substituent.

[0139] The “heteroarylene group” is, for example, a heteroarylene group having 2 to 30 carbon atoms, preferably a heteroarylene group having 2 to 25 carbon atoms, a heteroarylene group having 2 to 20 carbon atoms, a heteroarylene group having 2 to 15 carbon atoms, or a heteroarylene group having 2 to 10 carbon atoms. In addition, the “heteroarylene group” is, for example, a divalent group such as a heterocycle containing 1 to 5 heteroatoms selected from oxygen, sulfur, and nitrogen as ring-constituting atoms in addition to carbon.

[0140] Specific examples of the "heteroarylene group" include a divalent group obtained by removing one hydrogen atom from the above-mentioned "heteroaryl group" (monovalent group).

[0141] The "diarylamino group" is an amino group substituted with two aryl groups, and the description of the above-mentioned "aryl group" can be referred to for details of the aryl group.

[0142] The "diheteroarylamino group" is an amino group substituted with two heteroaryl groups, and the description of the "heteroaryl group" can be referred to for details of the heteroaryl group.

[0143] The "arylheteroarylamino group" is an amino group substituted with an aryl group or a heteroaryl group, and the description of the above-mentioned "aryl group" and "heteroaryl group" can be cited for the details of the above-mentioned aryl group and heteroaryl group.

[0144] The two aryl groups in the diarylamino group as the first substituent may be bonded to each other via a linking group, the two heteroaryl groups in the diheteroarylamino group as the first substituent may be bonded to each other via a linking group, and the aryl and heteroaryl groups in the arylheteroarylamino group as the first substituent may be bonded to each other via a linking group. Here, the description of "bonding via a linking group" is as shown below, for example, it means that the two phenyl groups of the diphenylamino group form a bond through a linking group. In addition, the description is also applicable to the diheteroarylamino group and the arylheteroarylamino group formed by aryl or heteroaryl groups.

[0145] [Chemistry 13]

[0146]

[0147] (* indicates the bond position)

[0148] Specific examples of the linking group include: >O, >NR X 、>C(-R X ) 2 、-C(-R X)=C(-R X )-、>Si(-R X ) 2 ,>S,>CO,>CS,>SO,>SO 2 、>SeO、>SeO 2 、>PO、>B(-R X ) and >Se. R X are independently alkyl, cycloalkyl, aryl, or heteroaryl, which may be substituted by alkyl, cycloalkyl, aryl, or heteroaryl. X ) 2 、-C(-R X )=C(-R X )-、>Si(-R X ) 2 Two R's X Can be linked to the group X via a single bond or Y bond with each other to form a ring. Y , can be listed as >O, >NR Y 、>C(-R Y ) 2 、>Si(-R Y ) 2 ,>S,>CO,>CS,>SO,>SO 2 , and>Se,R Y are independently alkyl, cycloalkyl, aryl or heteroaryl, which may be substituted by alkyl, cycloalkyl, aryl or heteroaryl. Y is>C(-R Y ) 2 and>Si(-R Y ) 2 In the case of two R Y The alkylene group may be substituted with an alkylene group. 2X Replacement, R 2X are independently alkyl, cycloalkyl, substituted silyl, aryl and heteroaryl, which may be substituted by alkyl, cycloalkyl, substituted silyl or aryl. X )=C(-R X )-The two Rs in X They may be bonded to each other and form an aryl ring (such as a benzene ring) or a heteroaryl ring together with these bonded C=C. X )=C(-R X )- can be an arylene group (such as 1,2-phenylene) or a heteroarylene group.

[0149] In addition, when simply describing “diarylamino”, “diheteroarylamino” or “arylheteroarylamino” in the present specification, unless otherwise specified, descriptions such as “two aryl groups in the diarylamino group may be bonded to each other via a linking group”, “two heteroaryl groups in the diheteroarylamino group may be bonded to each other via a linking group” and “the aryl and heteroaryl groups in the arylheteroarylamino group may be bonded to each other via a linking group” are respectively added.

[0150] The "diarylboryl group" is a boron group substituted with two aryl groups. The details of the aryl group can be referred to the description of the "aryl group". In addition, the two aryl groups can be linked by a single bond or a linking group (for example, -CH=CH-, -CR=CR-, -C≡C-, >NR, >O, >S, >C=O, >C=S, >S=O, >S(=O) 2 、>Se(=O)、>Se(=O) 2 ,>P(=O),>B(-R),>C(-R) 2 、>Si(-R) 2 Here, the R of -CR=CR-, >R of NR, >R of B(-R), >C(-R) 2 R, and R>Si(-R) is aryl, heteroaryl, diarylamino, alkyl, alkenyl, alkynyl, cycloalkyl, alkoxy, or aryloxy, and at least one hydrogen in the R can be further replaced by aryl, heteroaryl, alkyl, alkenyl, alkynyl, or cycloalkyl. In addition, two adjacent Rs can be bonded to each other to form a ring, and form a cycloalkylene, arylene, and heteroarylene. For the details of the substituents listed here, the descriptions of "aryl", "arylene", "heteroaryl", "heteroarylene", and "diarylamino" described above, and the descriptions of "alkyl", "alkenyl", "alkynyl", "cycloalkyl", "cycloalkylene", "alkoxy", and "aryloxy" described later can be cited. In addition, in this specification, when it is recorded only as "diarylboryl", as long as there is no special description, it is assumed that the description of "the two aryl groups of diarylboryl can be bonded to each other via a single bond or a linking group" is added.

[0151] "Alkyl" can be any of straight chain and branched chain, for example, a straight chain alkyl group with 1 to 24 carbon atoms or a branched chain alkyl group with 3 to 24 carbon atoms, preferably an alkyl group with 1 to 18 carbon atoms (branched chain alkyl group with 3 to 18 carbon atoms), an alkyl group with 1 to 12 carbon atoms (branched chain alkyl group with 3 to 12 carbon atoms), an alkyl group with 1 to 6 carbon atoms (branched chain alkyl group with 3 to 6 carbon atoms), an alkyl group with 1 to 5 carbon atoms (branched chain alkyl group with 3 to 5 carbon atoms), an alkyl group with 1 to 4 carbon atoms (branched chain alkyl group with 3 to 4 carbon atoms), etc.

[0152] Specific examples of “alkyl” include methyl, ethyl, n-propyl, isopropyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1,2-trimethylpropyl, 1,1,2,2-tetramethylpropyl, 1-ethyl-1,2,2-trimethylpropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-ethylbutyl, 1,1-dimethylbutyl, 3,3-dimethylbutyl, 1,1-diethylbutyl, 1-ethyl-1-methylbutyl, 1-propyl-1-methylbutyl, 1,1,3-trimethylbutyl, 1-ethyl-1,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, t-pentyl (t-amyl), 1-methylpentyl, 2-propylpentyl, 1,1-dimethylpentyl, 1-ethyl-1-methylpentyl, 1-propyl-1-methylpentyl, 1-butyl-1-methylpentyl, 1,1,4-trimethylpentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 1,1-dimethylhexyl, 1-ethyl-1-methylhexyl, 1,1,5-trimethylhexyl, 3,5,5-trimethylhexyl, n-heptyl, 1-methylheptyl, 1-hexylheptyl, 1,1-dimethylheptyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, n-octyl, tert-octyl (1,1,3,3-tetramethylbutyl), 1,1-dimethyloctyl, n-nonyl, n-decyl, 1-methyldecyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, or n-icosyl.

[0153] The "alkylene group" is a divalent group obtained by removing any hydrogen atom from an "alkyl group", and examples thereof include a methylene group, an ethylene group, and a propylene group.

[0154] Regarding the "alkenyl group", please refer to the description of the "alkyl group". It is a group in which the CC single bond in the structure of the "alkyl group" is replaced by a C=C double bond, and also includes a group in which not only one but more than two single bonds are replaced by double bonds (also called a diene group or a triene group).

[0155] Specific examples of the "alkenyl group" include alkenyl groups having 2 to 30 carbon atoms, preferably alkenyl groups having 2 to 20 carbon atoms, more preferably alkenyl groups having 2 to 10 carbon atoms, further preferably alkenyl groups having 2 to 6 carbon atoms, and particularly preferably alkenyl groups having 2 to 4 carbon atoms. Preferred alkenyl groups are ethenyl, 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.

[0156] The "alkenylene group" is a divalent group obtained by removing any hydrogen atom of an "alkenyl group", and examples thereof include a vinylene group.

[0157] Regarding the “alkynyl group”, reference may be made to the description of the “alkyl group”, which is a group in which the C-C single bond in the structure of the “alkyl group” is replaced by a C≡C triple bond, and also includes a group in which not only one but two or more single bonds are replaced by triple bonds (also called a di-alkynyl group or a tri-alkynyl group).

[0158] The “cycloalkyl group” is, for example, a cycloalkyl group having 3 to 24 carbon atoms, preferably a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, a cycloalkyl group having 5 to 6 carbon atoms, or a cycloalkyl group having 5 carbon atoms.

[0159] Specific examples of "cycloalkyl" include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, or alkyl (especially methyl) substituents having 1 to 5 carbon atoms or 1 to 4 carbon atoms, bicyclo[1.1.0]butyl, bicyclo[1.1.1]pentyl, bicyclo[2.1.0]pentyl, bicyclo[2.1.1]hexyl, bicyclo[3.1.0]hexyl, bicyclo[2.2.1]heptyl (norbornyl), bicyclo[2.2.2]octyl, adamantyl, diadamantyl, decahydronaphthyl, or decahydroazulyl.

[0160] The “cycloalkylene group” is, for example, a cycloalkylene group having 3 to 24 carbon atoms, preferably a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkylene group having 3 to 16 carbon atoms, a cycloalkylene group having 3 to 14 carbon atoms, a cycloalkylene group having 3 to 12 carbon atoms, a cycloalkylene group having 5 to 10 carbon atoms, a cycloalkylene group having 5 to 8 carbon atoms, a cycloalkylene group having 5 to 6 carbon atoms, or a cycloalkylene group having 5 carbon atoms.

[0161] Specific examples of the "cycloalkylene group" include a structure in which one hydrogen atom is removed from the above-mentioned "cycloalkyl group" (monovalent group) to give a divalent group.

[0162] The "cycloalkenyl group" can be exemplified by a group having a structure in which at least one single bond between two carbon atoms in the "cycloalkyl group" becomes a double bond (e.g., -CH 2 -CH 2 - is substituted with -CH=CH-), and is not equivalent to an aryl group. Specific examples thereof include 1-cyclohexenyl and 1-cyclopentenyl.

[0163] The "alkoxy group" is a group represented by "Alk-O-(Alk is an alkyl group)", and the description of the "alkyl group" can be cited for details of the alkyl group.

[0164] The "aryloxy group" is a group represented by "Ar-O-(Ar is an aryl group)", and the description of the "aryl group" can be cited for details of the aryl group.

[0165] The "arylthio group" is a group represented by "Ar-S-(Ar is an aryl group)", and the description of the "aryl group" can be cited for details of the aryl group.

[0166] The “substituted silyl group” is, for example, a silyl group substituted with at least one of an aryl group, an alkyl group, and a cycloalkyl group, and is preferably a triarylsilyl group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group, or an alkyldicycloalkylsilyl group.

[0167] The "triarylsilyl group" is a silyl group substituted with three aryl groups, and the description of the "aryl group" can be cited for details of the aryl groups.

[0168] Specific examples of the “triarylsilyl group” include triphenylsilyl, diphenylmononaphthylsilyl, monophenyldinaphthylsilyl, and trinaphthylsilyl groups.

[0169] The “trialkylsilyl group” is a silyl group substituted with three alkyl groups, and the description of the “alkyl group” mentioned above can be referred to for details of the alkyl groups.

[0170] Specific examples of “trialkylsilyl” include trimethylsilyl, triethylsilyl, tri-n-propylsilyl, triisopropylsilyl, tri-n-butylsilyl, triisobutylsilyl, tri-sec-butylsilyl, tri-tert-butylsilyl, ethyldimethylsilyl, n-propyldimethylsilyl, isopropyldimethylsilyl, n-butyldimethylsilyl, isobutyldimethylsilyl, sec-butyldimethylsilyl, tert-butyldimethylsilyl, methyldiethylsilyl, n-propyldimethylsilyl, tert-butyldiethylsilyl, methyldi-n-propylsilyl, ethyldi-n-propylsilyl, n-butyldi-n-propylsilyl, sec-butyldi-n-propylsilyl, tert-butyldi-n-propylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, n-butyldiisopropylsilyl, sec-butyldiisopropylsilyl, or tert-butyldiisopropylsilyl.

[0171] The "tricycloalkylsilyl group" is a silyl group substituted with three cycloalkyl groups, and the description of the "cycloalkyl group" mentioned above can be cited for the details of the cycloalkyl group.

[0172] Specific examples of the “tricycloalkylsilyl group” include tricyclopentylsilyl and tricyclohexylsilyl groups.

[0173] The "dialkylcycloalkylsilyl group" is a silyl group substituted with two alkyl groups and one cycloalkyl group, and the description of the "alkyl group" and the "cycloalkyl group" can be cited for details of the alkyl group and the cycloalkyl group.

[0174] The "alkyldicycloalkylsilyl group" is a silyl group substituted with one alkyl group and two cycloalkyl groups, and the description of the "alkyl group" and the "cycloalkyl group" can be cited for details of the alkyl group and the cycloalkyl group.

[0175] The "halogen" is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine, further preferably fluorine.

[0176] When substituted with a cyano group or a halogen, it is also preferred that all or part of the hydrogen atoms in the aryl group or the heteroaryl group in the structure are substituted with a cyano group or a halogen.

[0177] The substituent represented by formula (A30) has the following structure.

[0178] [Chemistry 14]

[0179]

[0180] In formula (A30),

[0181] Ak is hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted cycloalkyl or substituted or unsubstituted cycloalkenyl, at least one of the alkyl, cycloalkyl and cycloalkenyl groups being -CH 2 - may be substituted by -O- or -S-,

[0182] R Ak is a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl or a substituted or unsubstituted cycloalkyl, R Ak It can be bonded to Ak through a linking group or a single bond, and * is the bonding position.

[0183] In formula (A30), Ak is the substituent, and is not conjugated with the non-covalent electron pair on N, so that the non-covalent electron pair can be conjugated with the π electron of the bonding target, and a larger wavelength change can be achieved compared to the case where an aromatic group or the like exists at the same position. In addition, the same is true for the influence on the multiple resonance effect, and a greater improvement in the thermally activated delayed fluorescence (TADF) property can be achieved.

[0184] R Ak Preferred is an aryl group which may be substituted by an alkyl group or a cycloalkyl group, a heteroaryl group which may be substituted by an alkyl group or a cycloalkyl group, an alkyl group or a cycloalkyl group, more preferably an aryl group which may be substituted by an alkyl group, a heteroaryl group which may be substituted by an alkyl group, an alkyl group or a cycloalkyl group, further preferably an aryl group which may be substituted by an alkyl group, and particularly preferably a phenyl group which may be substituted by a methyl group.

[0185] In formula (A30), Ak is preferably an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 3 to 8 carbon atoms, further preferably an alkyl group having 1 to 4 carbon atoms, and particularly preferably a methyl group.

[0186] R Ak It may be the same as or different from Ak, but is preferably different.

[0187] R Ak It can be bonded to Ak via a linking group or a single bond. Examples of the linking group in this case include: >O, >S or >Si(-R) 2 etc. >Si(-R) 2 R is hydrogen, an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 14 carbon atoms. Ak Examples of the structure bonded to Ak via a linking group or a single bond include the following structures.

[0188] [Chemistry 15]

[0189]

[0190] In the above formulas, * represents the bonding position.

[0191] [When two groups bonded to the same atom bond to each other]

[0192] In the present specification, when two groups bonded to the same atom are said to be bonded to each other to form a ring, they may be bonded via a single bond or a linking group (these are also collectively referred to as a linking group). Examples of the linking group include -CH 2 -CH 2 -、-CHR-CHR-、-CR 2 -CR 2 -, -CH=CH-, -CR=CR-, -C≡C-, -N(-R)-, -O-, -S-, -C(-R) 2 -, -C(=O)-, -C(=S)-, -S(=O)-, -S(=O) 2 -, -Se(=O)-, -Se(=O) 2 -, -P(=O)-, -B(-R)-, -Si(-R) 2 - or -Se-, for example, the following structures can be cited. In addition, R, -CR 2 -CR 2 -R, -CR=CR-R, -N(-R)-R, -C(-R) 2 -R, -B(-R)-R and -Si(-R) 2-R are independently hydrogen, aryl which may be substituted by alkyl or cycloalkyl, heteroaryl which may be substituted by alkyl or cycloalkyl, alkyl which may be substituted by cycloalkyl, alkenyl which may be substituted by alkyl or cycloalkyl, alkynyl which may be substituted by alkyl or cycloalkyl, or cycloalkyl which may be substituted by alkyl or cycloalkyl. In addition, two adjacent R may be bonded to each other to form a ring, and may form a cycloalkylene, arylene, or heteroarylene.

[0193] [Chemistry 16]

[0194]

[0195] As the bonding group, a single bond, -CR=CR-, -N(-R)-, -O-, -S-, -C(-R)- as a linking group are preferred. 2 -、-Si(-R) 2 -, and -Se-, more preferably a single bond, -CR=CR-, -N(-R)-, -O-, -S-, and -C(-R)- as a linking group 2 -, more preferably a single bond, -CR=CR-, -N(-R)-, -O-, and -S- as a linking group, and most preferably a single bond.

[0196] The position at which the two Rs are bonded via a bonding group is not particularly limited as long as it is a position at which bonding is possible, but it is preferred that the two Rs are bonded at the most adjacent position. For example, when the two groups are phenyl groups, it is preferred that the two Rs are bonded to each other at the ortho position (position 2) based on the bonding position (position 1) of "C" or "Si" in the phenyl group (refer to the structural formula).

[0197] <Stereoisomers, etc.>

[0198] The polycyclic aromatic compound of the present invention may exist as enantiomers or diastereomers depending on the type of substituents, but any stereoisomer in any pure form, any mixture of stereoisomers, racemates, etc. are all included in the scope of the present invention regardless of the structural formula described.

[0199] 1. Polycyclic aromatic compounds

[0200] <Overall structure>

[0201] Regarding polycyclic aromatic compounds formed by linking aromatic rings using heteroelements such as boron, nitrogen, oxygen, and sulfur, it has been found that they have a large highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap (band gap Eg in the film). The reason is that the aromaticity of the 6-membered ring containing the heteroelement is low, and the reduction of the HOMO-LUMO gap accompanying the expansion of the conjugated system is suppressed. In addition, it was found that the HOMO-LUMO gap can be arbitrarily changed according to the type of heteroelement and the method of connection. It is believed that the reason is that the energy of HOMO and LUMO can be arbitrarily changed according to the spatial expansion and energy of the empty orbital or lone pair of the heteroelement.

[0202] These polycyclic aromatic compounds cause the excited state singly occupied molecular orbital (SOMO) 1 and SOMO 2 to be localized on each atom due to the electronic disturbance of the heteroelement, thereby narrowing the half-value width of the fluorescence emission peak, and thus obtaining high color purity emission when used as a dopant for an organic EL element. S1T1 It becomes smaller and exhibits thermally activated delayed fluorescence, and when used as an emitting dopant in an organic EL element, high efficiency can be obtained.

[0203] Furthermore, by introducing a substituent, the energies of HOMO and LUMO can be arbitrarily changed, and thus the ionization potential and the electron affinity can be optimized according to the surrounding materials.

[0204] In the present invention, it was found that, in particular, polycyclic aromatic compounds having a structure composed of one or more structural units represented by formula (1) containing specific groups, as the polycyclic aromatic compounds, can produce organic electroluminescent elements with longer life and higher luminous efficiency than polycyclic aromatic compounds with similar structures.

[0205] The polycyclic aromatic compound of the present invention corresponds to a polycyclic aromatic compound formed by linking aromatic rings such as a benzene ring using nitrogen and boron. The polycyclic aromatic compound of the present invention has a structure consisting of one or more structural units represented by formula (1), and has a specific substituent. In addition, in this specification, a polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1) is sometimes referred to as a "polycyclic aromatic compound containing a structural unit represented by formula (1)".

[0206] [Chemistry 17]

[0207]

[0208] In formula (1), at least one selected from the group consisting of ring A, ring B and ring C contains at least one group represented by formula (G) as a substituent, and at least one of Ar in the structure composed of one or more structural units represented by formula (1) is a monovalent group represented by formula (Ar).

[0209] [Chemistry 18]

[0210]

[0211] In the present invention, it is found that by having a structure represented by formula (Ar) at a predetermined position of a polycyclic aromatic compound, the efficiency of an organic EL element using the compound is further increased and the life is further prolonged. The reason is believed to be that the interaction with adjacent molecules is suppressed by covering at least one face of the main skeleton with a substituent in an ortho position relative to the bonding position of the monovalent group represented by formula (Ar). In particular, in TADF assisting fluorescence (TAF) elements or phosphor-sensitized fluorescent (PSF) elements, the emitting dopant becomes the lowest excited triplet state (T1 state) due to Dexter-type energy transfer, which becomes a factor of reduced efficiency and shortened life. However, if the molecules are not in contact, Dexter-type energy transfer will not occur, so the reason is believed to be that the T1 state can be avoided by suppressing the interaction between molecules.

[0212] However, the present invention is not particularly limited to these principles.

[0213] The following describes in detail the polycyclic aromatic compound including the structural unit represented by formula (1).

[0214] <Description of Ring Structure in Compound>

[0215] In formula (1), "A", "B", and "C" in the circle are symbols representing the ring structure represented by each circle. The structure represented by formula (1) has a structure in which at least three aromatic rings as the A ring, the B ring, and the C ring are connected by boron and nitrogen to form a ring structure. The formed ring structure is a condensed ring structure composed of at least 5 rings.

[0216] The A ring, the B ring and the C ring are each independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring.

[0217] Ring A forms a trivalent group having a bond on three consecutive atoms (preferably carbon) on the ring of the aryl ring or heteroaryl ring in its structure. Ring A is bonded to two N (nitrogen) and B (boron) through the three bonds. The ring in which the atom having the bond is set as the ring-constituting atom in Ring A is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring. The ring can be further condensed with other rings. Examples of 6-membered rings include: benzene ring, pyridine ring, pyrazine ring, pyrimidine ring, etc. Examples of 6-membered rings further condensed with other rings include: naphthalene ring, quinoline ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, etc. Examples of 5-membered rings include: furan ring, thiophene ring, pyrrole ring, thiazole ring, etc. Examples of 5-membered rings further condensed with other rings include: benzofuran ring, benzothiophene ring, indole ring, etc. In addition, as a condensed ring, an indene ring can also be listed.

[0218] The aryl ring or heteroaryl ring in the A ring is preferably a benzene ring.

[0219] Both the B ring and the C ring form a divalent group with a bond on two atoms (preferably carbon) adjacent to each other on the ring of the aryl ring or heteroaryl ring in its structure. The B ring is bonded to N (nitrogen) and B (boron) through the two bonds, and the C ring is bonded to N (nitrogen) and B (boron) through the two bonds. The ring in which the atoms having the two bonds are set as the ring-constituting atoms in each of the B ring and the C ring is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring. The ring can be further condensed with other rings. As examples of 6-membered rings, benzene rings, pyridine rings, pyrazine rings, pyrimidine rings, etc. can be listed. As examples of 6-membered rings further condensed with other rings, naphthalene rings, quinoline rings, benzofuran rings, benzothiophene rings, indole rings, benzoselenophene rings, dibenzofuran rings, dibenzothiophene rings, carbazole rings, dibenzoselenophene rings, etc. can be listed. Examples of 5-membered rings include furan rings, thiophene rings, pyrrole rings, thiazole rings, selenophene rings, etc. Examples of 5-membered rings condensed with other rings include benzofuran rings, benzothiophene rings, indole rings, benzoselenophene rings, etc. In addition, indene rings may also be included as condensed rings.

[0220] The aryl ring or heteroaryl ring in the B ring or the C ring is preferably a benzene ring, a benzofuran ring, a benzothiophene ring, an indene ring or a benzoselenophene ring, more preferably a benzene ring, a benzofuran ring, an indene ring or a benzothiophene ring, and further preferably a benzene ring or a benzothiophene ring.

[0221] In the substituted or unsubstituted aryl ring or substituted or unsubstituted heteroaryl ring in the A ring, the substituent mentioned when "substituted or unsubstituted (substituted or unsubstituted)" includes the group represented by the formula (G) described below. At least one selected from the group consisting of the A ring, the B ring and the C ring includes at least one group represented by the formula (G) as a substituent. As other substituents, at least one substituent selected from the substituent group Zα can be mentioned. In addition, the substituent may also be a substituted or unsubstituted diarylphosphino group such as a diphenylphosphino group. When there are multiple substituents, the multiple substituents may be the same or different from each other. As a substituent other than the group represented by the formula (G), preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group (excluding the group represented by the formula (G)), or a substituted or unsubstituted diarylamino group, more preferably a tert-butyl group, an adamantyl group, or a substituted or unsubstituted diphenylamino group. As other preferred substituents, reference can be made to the description in <Preferred substituents> described later.

[0222] <Group represented by formula (G)>

[0223] At least one selected from the group consisting of ring A, ring B and ring C contains at least one group represented by formula (G) as a substituent. That is, in the structure consisting of one of the structural units represented by formula (1), at least one selected from the group consisting of one ring A, one ring B and one ring C contains at least one group represented by formula (G) as a substituent. In the structure consisting of two or more of the structural units represented by formula (1), at least one selected from the group consisting of at least one ring A, at least one ring B and at least one ring C contained in the structure contains at least one group represented by formula (G) as a substituent.

[0224] [Chemistry 19]

[0225]

[0226] In formula (G), # represents the bonding position to the aryl ring or heteroaryl ring in ring A, ring B or ring C. That is, the group represented by formula (G) is directly bonded to the aryl ring or heteroaryl ring forming a trivalent group or a divalent group as described above at #.

[0227] In formula (G), ring D and ring E are independently a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring, wherein either of them may be a substituted or unsubstituted cycloalkane ring.

[0228] Both the D ring and the E ring have a bond on two atoms (preferably carbon) adjacent to each other on the aryl ring or heteroaryl ring in its structure. The D ring is bonded to N (nitrogen) and the E ring using the two bonds, and the E ring is bonded to N (nitrogen) and the D ring using the two bonds. In each of the D ring and the E ring, the ring in which the atoms having the two bonds are set as the ring-constituting atoms is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring. The ring can be further condensed with other rings. As examples of 6-membered rings, benzene rings, pyridine rings, pyrazine rings, pyrimidine rings, etc. can be cited. As examples of 6-membered rings further condensed with other rings, naphthalene rings, quinoline rings, benzofuran rings, benzothiophene rings, indole rings (preferably 1-phenyl-1H-indole rings), benzoselenophene rings, dibenzofuran rings, dibenzothiophene rings, carbazole rings (preferably N-phenyl-carbazole rings), dibenzoselenophene rings, etc. Examples of 5-membered rings include furan rings, thiophene rings, pyrrole rings, thiazole rings, selenophene rings, etc. Examples of 5-membered rings condensed with other rings include benzofuran rings, benzothiophene rings, indole rings, benzoselenophene rings, etc. In addition, indene rings may also be included as condensed rings.

[0229] The aryl ring or heteroaryl ring in the D ring and the E ring is preferably a benzene ring, a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring or a naphthalene ring, and more preferably a benzene ring.

[0230] Either of the D ring and the E ring may be a substituted or unsubstituted cycloalkane ring. Examples of the cycloalkane ring include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, and a cyclooctane ring, and a cyclohexane ring is preferred.

[0231] In the substituted or unsubstituted aryl ring, substituted or unsubstituted heteroaryl ring, or substituted or unsubstituted cycloalkane ring in the D ring and the E ring, as the substituent when referring to "substituted or unsubstituted (substituted or unsubstituted)", at least one substituent selected from the substituent group Zα can be listed. In addition, the substituent may also be a substituted or unsubstituted diarylphosphino group such as a diphenylphosphino group. When there are multiple substituents, the multiple substituents may be the same or different from each other. As the substituent, preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, more preferably a methyl group, a tert-butyl group, a phenyl group, or a carbazolyl group. Both the D ring and the E ring are particularly preferably a substituted aryl ring or an unsubstituted heteroaryl ring.

[0232] The group represented by formula (G) is preferably a group represented by formula (G-1).

[0233] [Chemistry 20]

[0234]

[0235] In formula (G-1), Z e are independently -N= or -C(-R 12 )=,R 12 are independently hydrogen or a substituent. e Relative to the four consecutive Z e Preferably, it is one or two, more preferably, it is one. e It is particularly preferred that both are -C(-R 12 )=. As R 12 When it is a substituent, the substituent may be at least one substituent selected from the substituent group Zα. When there are multiple substituents, the multiple substituents may be the same or different from each other. As a substituent, preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, more preferably a methyl group, a tert-butyl group, a phenyl group or a carbazolyl group. In formula (G-1), R 12 -C(-R 12 ) = relative to four consecutive Z e Preferably, it is one or two, and more preferably, it is one. 12 Particularly preferably, both are hydrogen.

[0236] Specific examples of the group represented by formula (G) include any of the following groups.

[0237] [Chemistry 21]

[0238]

[0239] [Chemistry 22]

[0240]

[0241] In the polycyclic aromatic compound containing the structural unit represented by formula (1), the number of the group represented by formula (G) in each structural unit is preferably 1 to 3, more preferably 1 to 2, and even more preferably 2.

[0242] <Ar>

[0243] Ar is independently a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, wherein, in a structure consisting of one or more structural units represented by formula (1), at least one of the Ars is a monovalent group represented by formula (Ar). That is, in a structure consisting of one structural unit represented by formula (1), at least one of the two Ars is a monovalent group represented by formula (Ar), and in a structure consisting of two or more structural units represented by formula (1), at least one of the (three or four or more) Ars in the structure is a monovalent group represented by formula (Ar).

[0244] [Chemistry 23]

[0245]

[0246] In the formula (Ar), * represents the bonding position of the monovalent group represented by the formula (Ar) to the nitrogen atom.

[0247] In the formula (Ar), R g1 ~R g4 are independently hydrogen or a substituent, R g1 ~R g4 The two adjacent groups in the group may be bonded to each other and form a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring together with the benzene ring to which they are bonded. Examples of the aryl ring formed include a naphthalene ring, an indene ring, and a fluorene ring. In addition, examples of the heteroaryl ring formed include a dibenzofuran ring and a dibenzothiophene ring. As the substituent of the aryl ring formed, see R g1 ~R g4 Description of a substituent.

[0248] In addition, R g1 ~R g4 The two adjacent groups in R are bonded to each other and together with the carbon atoms to which they are bonded form a cycloolefin structure. The structure is equivalent to g1 ~R g4 The structure of a cycloalkane condensed on the bonded benzene ring. g2 and R g3 Preferred examples include structures in which the components are bonded to each other to form a partial structure represented by formula (B11) or formula (B12) described later.

[0249] In the formula (Ar), R g1 ~R g4When R is a substituent, the substituent may be at least one substituent selected from the substituent group Zα. When there are multiple substituents, the multiple substituents may be the same or different from each other. As a substituent, preferably, it is a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and more preferably, it is an adamantyl group, a tert-butyl group or a phenyl group. g1 ~R g4 In the formula (R), the substituent may be one or two. g1 ~R g4 All of them can be hydrogen. g1 ~R g4 The molecular weight of the polycyclic aromatic compound containing the structural unit represented by the formula (1) can be adjusted to a range suitable for sublimation purification by adjusting the type and number of the substituents introduced therein.

[0250] In formula (Ar), Z is independently -C(-R Z )=or-N=, at least one set of adjacent as-C(-R Z )=Z can be in R Z They are bonded to each other to form a ring. Z are each independently hydrogen or a substituent.

[0251] In formula (Ar), it is preferred that the following condition A is satisfied.

[0252] (Condition A) At least one Z is R Z -C(-R Z )=, or any set of adjacent Z in R Z They are bonded to each other to form a ring.

[0253] In particular, when the A ring, the B ring and the C ring (especially the B ring and the C ring) are all substituted or unsubstituted aryl rings, it is preferred to satisfy condition A. In the formula (Ar) satisfying condition A, any adjacent -C (-R Z )=Z is not in R Z When the substituents are bonded to each other to form a ring, it is more preferable that R Z When the number of substituents other than hydrogen atoms is 4 or less (preferably 5 or less), at least two Z are R Z -C(-R Z )=, and unlike this, it is more preferable that R as a substituent Z When only unsubstituted alkyl is present, at least two Z are R Z -C(-R Z )=.

[0254] The polycyclic aromatic compound of the present invention has a monovalent group represented by the formula (Ar) as an ortho-substituted phenyl structure, thereby having a structure in which the group at the ortho position relative to the bonding position with nitrogen is more bulky. In addition, the polycyclic aromatic compound of the present invention also has a substituent or a condensed ring structure as R in the formula (Ar) as described above. Z , whereby in formula (Ar), the volume of the base in the ortho position relative to the bonding position with nitrogen becomes larger. Therefore, as described above, the interaction with the adjacent molecules is suppressed, and particularly in the TAF element or the PSF element, the generation of the emitting dopant in the T1 state is suppressed, and in the organic electroluminescent element using the polycyclic aromatic compound containing the structural unit represented by formula (1), the luminous efficiency is improved.

[0255] On the other hand, the polycyclic aromatic compound of the present invention in which any one of the A ring, the B ring, and the C ring is a substituted or unsubstituted heteroaryl ring may have a substituent or a condensed ring structure as R in the formula (Ar) as described above. Z In the case of, high luminous efficiency and the like can also be obtained. From the viewpoint of high color purity (narrow luminous spectrum), it is particularly preferred to include a structure of a heteroaryl ring having a nitrogen atom in the ortho and / or para position relative to the carbon to which the nitrogen in N-Ar is bonded. In addition, from the viewpoint of high color purity (narrow luminous spectrum), it is preferred that the A ring is a substituted or unsubstituted pyridine ring or a substituted or unsubstituted pyrimidine ring, and from the viewpoint of ease of synthesis, it is preferred that the B ring and / or the C ring be a substituted or unsubstituted pyridine ring or a substituted or unsubstituted pyrimidine ring. Furthermore, from the viewpoint of high structural stability and high luminous efficiency, it is preferred that either the B ring or the C ring is a heteroaryl ring (which may have a substituent) containing a 5-membered ring, and more preferably a benzothiophene ring or a benzofuran ring (which may have a substituent).

[0256] In the formula (Ar), the number of Z as -N= is preferably 1 or 2, and more preferably 1. It is particularly preferred that all Zs are -C(-R Z )=. As R Z When Z is a substituent, the substituent may be at least one substituent selected from the substituent group Zα. When there are multiple substituents, the multiple substituents may be the same or different from each other. In formula (Ar), when any adjacent Z is not in R Z When they are bonded to each other to form a ring, R Z -C(-R Z )= is 1 to 3, and the others are preferably hydrogen. Wherein, as described above, when R as a substituent Z When the number of substituents other than hydrogen atoms is 4 or less or when the alkyl group is unsubstituted (particularly when the A ring, the B ring and the C ring are all substituted or unsubstituted aryl rings), RZ -C(-R Z )= is 2 to 3, and the rest is preferably hydrogen.

[0257] Formula (Ar) preferably contains at least one substituent selected from the substituent group ZA1 as R Z , the substituent group ZA1 may be substituted by at least one substituent selected from the substituent group ZB1.

[0258] Substituent group ZA1: aryl, heteroaryl, alkyl, cycloalkyl, arylalkyl, diarylamino, diheteroarylamino, arylheteroarylamino, triarylsilyl, diarylmonoalkylsilyl, monoaryldialkylsilyl, trialkylsilyl, monoarylmonoalkylamino, dialkylamino, diphenylphosphoryl, aryloxy, arylthio and diarylboryl;

[0259] Substituent group ZB1: aryl, heteroaryl, alkyl, cycloalkyl, cyano and halogen.

[0260] The formula (Ar) particularly preferably contains as R at least one substituent selected from the following groups Z :

[0261] Aryl, which may be substituted by at least one substituent selected from the substituent group ZB1;

[0262] Heteroaryl may be substituted with at least one substituent selected from the substituent group ZB1;

[0263] Arylalkyl may be substituted with at least one substituent selected from the substituent group ZB1;

[0264] The diarylamino group may be substituted with at least one substituent selected from the substituent group ZB1;

[0265] The diheteroarylamino group may be substituted with at least one substituent selected from the substituent group ZB1;

[0266] Arylheteroarylamino may be substituted with at least one substituent selected from the substituent group ZB1;

[0267] The triarylsilyl group may be substituted with at least one substituent selected from the substituent group ZB1;

[0268] The aryloxy group may be substituted by at least one substituent selected from the substituent group ZB1;

[0269] An arylthio group may be substituted with at least one substituent selected from the substituent group ZB1; and

[0270] The diarylboryl group may be substituted with at least one substituent selected from the substituent group ZB1.

[0271] The formula (Ar) is particularly preferably a substituent comprising, as R, at least one substituent selected from the group consisting of a phenyl group, an N-carbonyl group, a pyridyl group, a diphenylamino group, a triphenylsilyl group, a phenoxy group, and a phenylthio group. Z These substituents may be substituted by one or two alkyl groups (preferably tert-butyl groups).

[0272] About adjacency as -C(-R Z )=Z in R Z Examples of rings formed by bonding with each other at the positions are as follows: Z )= carbon is a ring-constituting atom) to form a ring, such as a naphthalene ring, an indene ring, a fluorene ring, a dihydronaphthalene ring, a dihydroanthracene ring, a benzofuran ring, a benzothiophene ring, etc. In addition, it is also preferred that two adjacent Zs are in R Z The structure is equivalent to -C(-R Z )= is a structure in which a cycloalkane is condensed on a benzene ring in which the carbon atom in the ring is a ring-constituting atom. In particular, two adjacent -C(-R Z )=Z in R Z A preferred example is a structure in which the ions are bonded to each other at positions to form a partial structure represented by the formula (B11) or the formula (B12) described later.

[0273] Examples of the monovalent group represented by the formula (Ar) include groups represented by any of the following formulae: In the formulae of the following groups, * represents a bonding position to a nitrogen atom, and Cy represents a cyclohexyl group.

[0274] [Chemistry 24]

[0275]

[0276] [Chemistry 25]

[0277]

[0278] [Chemistry 26]

[0279]

[0280] Ar may be a monovalent group represented by formula (Ar) or any one of them may be a monovalent group represented by formula (Ar). When a plurality of Ar are monovalent groups represented by formula (Ar), the monovalent groups represented by the plurality of formula (Ar) may be the same or different, but are preferably the same from the viewpoint of easy synthesis.

[0281] Ar which is not a monovalent group represented by the formula (Ar) is preferably a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, more preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted dibenzofuranyl group, further preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted dibenzofuranyl group, particularly preferably a phenyl group which may be substituted with an alkyl group or a cycloalkyl group, a biphenyl group which may be substituted with an alkyl group or a cycloalkyl group, 4-p-terphenyl group which may be substituted with an alkyl group or a cycloalkyl group, 4′-m-terphenyl group which may be substituted with an alkyl group or a cycloalkyl group, or a substituted or unsubstituted dibenzofuranyl group (particularly 4-dibenzofuranyl group).

[0282] Preferred specific examples of Ar which is not a monovalent group represented by the formula (Ar) are shown below. In addition, * represents a bonding position to a nitrogen atom.

[0283] [Chemistry 27]

[0284]

[0285] Ar which is not a monovalent group represented by the formula (Ar) may be bonded to at least one of the A ring, the B ring, and the C ring via a linking group or a single bond. Examples of the linking group in this case include: -CH 2 -CH 2 -、-CHR-CHR-、-CR 2 -CR 2 -, -CH=CH-, -CR=CR-, -C≡C-, -N(-R)-, -O-, -S-, -C(-R) 2 -, -C(=O)-, -C(=S)-, -S(=O)-, -S(=O) 2 -, -Se(=O)-, -Se(=O) 2 -, -P(=O)-, -B(-R)-, -Si(-R) 2 - or -Se-, etc. Among these, -CH=CH-, -CR=CR-, -N(-R)-, -O-, -S-, and -C(-R) are preferred. 2 -, more preferably -CH=CH-, -CR=CR-, -N(-R)-, -O-, and -S-, and even more preferably -CR=CR-, -N(-R)-, -O-, and -S-. 2 -CR 2 -”, “-CR=CR-”, “-N(-R)-”, “-C(-R) 2-"R, and "-Si(-R) 2 -" are independently hydrogen, aryl which may be substituted by alkyl or cycloalkyl, heteroaryl which may be substituted by alkyl or cycloalkyl, alkyl which may be substituted by alkyl or cycloalkyl, alkenyl which may be substituted by alkyl or cycloalkyl, alkynyl which may be substituted by alkyl or cycloalkyl, or cycloalkyl which may be substituted by alkyl or cycloalkyl. In addition, two R bonded to the same atom may bond to each other to form a ring. Furthermore, two adjacent R may bond to each other to form a cycloalkylene ring, an arylene ring, and a heteroarylene ring. In addition, these rings may also be substituted by alkyl or cycloalkyl.

[0286] Examples of the condensed ring formed by bonding Ar to the benzene ring as an aryl ring in the A ring, the B ring or the C ring include: a carbazole ring (where R is a phenyl group); NX through a single bond), a phenoxazine ring (a phenyl group R NX through -O-bonding), phenothiazine ring (phenyl R NX through -S-bonding) or acridone ring (phenyl R NX through a -C(=O)- bond).

[0287] In addition, the following partial structure (A10) may be formed by the connection as described above.

[0288] [Chemistry 28]

[0289]

[0290] In formula (A10), R A1 ~R A4 are independently hydrogen, alkyl or cycloalkyl, R A1 ~R A4 Any two to four of may be bonded to each other via a linking group or a single bond, and may be bonded to one of the two rings bonded to X at the two * positions, and bonded to the other ring at the ** position. That is, N in formula (A10) is X>NR X When>NR X N. The atoms on the ring that are bonded at the two * positions only need to be adjacent atoms (preferably carbon atoms). The partial structure represented by formula (A10) includes a NC bond with a weak bond dissociation energy (BDE), but the presence of another bond that forms the ring also promotes the reverse reaction (rebonding reaction) when the NC bond breaks, thus becoming a more stable structure. Therefore, in an organic EL element manufactured using a polycyclic aromatic compound having such a structure, it can be expected that the element life will be extended. When the structure represented by formula (A10) is included in the polycyclic aromatic compound, the number thereof can be one or two (preferably one).

[0291] In formula (A10), R A1 ~R A4 Any two to four of may be linked to each other via a linking group or a single bond.

[0292] R A1 ~R A4 Preferably, any two (R A1 and R A4 , R A1 and R A4 and R A2 and R A3 , R A1 and R A2 , R A3 and R A4 , R A1 and R A2 and R A3 and R A4 ) are bonded to each other through a linking group or a single bond, and more preferably R A1 and R A4 The two groups are bonded to each other through a linking group or a single bond. As a divalent group formed by bonding to each other, an alkylene group can be cited. At least one hydrogen in the alkylene group may be substituted by an alkyl group or a cycloalkyl group, and at least one (preferably one) -CH 2 - may be substituted by -O- and -S-. The divalent group formed by mutual bonding is preferably a straight-chain alkylene group having 2 to 5 carbon atoms, more preferably a straight-chain alkylene group having 3 or 4 carbon atoms, and still more preferably a straight-chain alkylene group having 4 carbon atoms (-(CH 2 ) 4 -). A straight-chain alkylene group having 4 carbon atoms (-(CH 2 ) 4 -) is particularly preferably unsubstituted.

[0293] The remaining R that is not involved in the link A1 ~R A4 Preferably, they are each independently hydrogen or an optionally substituted alkyl group, more preferably an optionally substituted alkyl group having 1 to 6 carbon atoms, further preferably an unsubstituted alkyl group having 1 to 6 carbon atoms, and most preferably, they are all methyl groups.

[0294] That is, the partial structure represented by formula (A10) is preferably a structure represented by the following formula (A11).

[0295] [Chemistry 29]

[0296]

[0297] In the formula (A11), the two * positions are bonded to one of the two rings bonded to nitrogen, and the ** position is bonded to the other ring.

[0298] <Structure composed of one or two or more structural units>

[0299] 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). As a polycyclic aromatic compound having a structure composed of one of the structural units, a polycyclic aromatic compound represented by formula (1) can be cited. As a polycyclic aromatic compound having a structure composed of two or more of the structural units represented by formula (1), a compound equivalent to a multimer of the polycyclic aromatic compound represented by the formula described above as the structural unit represented by formula (1) can be cited. The multimer is preferably a dimer to a hexamer, more preferably a dimer to a trimer, and particularly preferably a dimer. The multimer can be any form as long as it has a plurality of the structural units in one compound, and can be a form in which any ring (a ring, b ring or c ring) contained in the structural unit is bonded in a manner that is shared by a plurality of structural units, and can also be a form in which any ring (a ring, b ring or c ring) contained in the structural unit is bonded by condensation with each other. In addition, the structural unit may be bonded to a plurality of groups using a single bond, an alkylene group having 1 to 3 carbon atoms, a phenylene group, a naphthylene group, or the like. Of these, a bonded group in a shared ring is preferred. The two or more structural units in the polycyclic aromatic compound having a structure composed of two or more structural units represented by formula (1) may be the same or different from each other.

[0300] <Polycyclic aromatic compound represented by formula (1-A), formula (1-B), formula (1-C) or formula (1-D)>

[0301] Preferred examples of the polycyclic aromatic compound containing the structural unit represented by formula (1) include polycyclic aromatic compounds represented by formula (1-A), formula (1-B), formula (1-C) or formula (1-D).

[0302] [Chemistry 30]

[0303]

[0304] In formula (1-A), formula (1-B), formula (1-C) and formula (1-D), Z C and Z d are independently -C(-R 11 )=or-N=, any one or more Z d =Z d or Z C =Z C Can be >O, >NR, >C(-R) 2、>Si(-R) 2 , >S or >Se. The >NR, the >C(-R) 2 And the above>Si(-R) 2 R are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and the >C(-R) 2 And the above>Si(-R) 2 The two R's may be bonded to each other to form a ring.

[0305] R 11 are independently hydrogen or a substituent, and a plurality of R 11 Adjacent groups in the group may be bonded to each other and form a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring together with the a ring, the b ring, the c ring, the c1 ring, the a' ring, the b' ring or the b'2 ring.

[0306] In each of formula (1-B) and formula (1-D), X c is >O、>NR NX 、>C(-R CX ) 2 、>Si(-R IX ) 2 , >S or >Se. NX , R CX and R IX are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and the two R CX Can bond to each other to form a ring, two R IX They may bond with each other to form a ring. NX , preferably a substituted or unsubstituted aryl group, more preferably a phenyl group which may be substituted by an alkyl group. CX , preferably methyl or phenyl. IX , preferably methyl or phenyl.

[0307] In each of the formulas (1-A), (1-B), (1-C) and (1-D), Z as -N= d Preferably, there are 1 or 2, more preferably 1, in the same monocyclic ring. d It is particularly preferred that both are -C(-R 11 )=. As R 11 When R is a substituent, at least one substituent selected from the substituent group Zα can be cited. When there are multiple substituents, the multiple substituents may be the same or different from each other. In each of formulas (1-A), (1-B), (1-C) and (1-D), R11 -C(-R 11 )=Z d The number of such moieties is preferably 0 to 2, and more preferably 0 to 1, in the same monocyclic ring.

[0308] In each of the formulas (1-B) and (1-D), Z as -N= C Preferably, it is 1 or 2, and more preferably, it is 1. C It is particularly preferred that both are -C(-R 11 )=. As Z C When R is a substituent, at least one substituent selected from the substituent group Zα can be cited. When there are multiple substituents, the multiple substituents may be the same or different from each other. In each of formulas (1-B) and (1-D), R 11 -C(-R 11 )=Z C Preferably, it is 0 to 2, and more preferably, it is 0 to 1.

[0309] In each of formula (1-B) and formula (1-D), X c Preferably >O, >C(-CH 3 ) 2 or >S, more preferably >S.

[0310] In each of formula (1-A), formula (1-B), formula (1-C) and formula (1-D), Ar has the same meaning as A in formula (1), and the preferred range is also the same. In each of formula (1-A), formula (1-B), formula (1-C) and formula (1-D), at least one of Ar is a monovalent group represented by formula (Ar).

[0311] <Preferred substituents>

[0312] In the polycyclic aromatic compounds used as emissive dopants (and in the compounds used as dopants), as a substituent containing an "alkyl group", a tertiary alkyl group represented by the following formula (tR) is one of the particularly preferred groups. The reason is that by such a bulky substituent, the intermolecular distance increases, and thus the luminescence quantum yield (photoluminescence quantum yield (PLQY)) is improved. In addition, it is also preferred that the tertiary alkyl group represented by the formula (tR) is substituted as a second substituent on other substituents. Specifically, a diarylamino group substituted with a tertiary alkyl group represented by the formula (tR), a carbazolyl group substituted with a tertiary alkyl group represented by the formula (tR) (preferably an N-carbazolyl group) or a benzocarbazolyl group substituted with a tertiary alkyl group represented by the formula (tR) (preferably an N-benzocarbazolyl group) can be listed. Examples of substitution forms of the group of formula (tR) for the diarylamino group, carbazolyl group and benzocarbazolyl group include a case where a part or all of the hydrogen atoms of the aryl ring or benzene ring in these groups are substituted with the group of formula (tR).

[0313] [Chemistry 31]

[0314]

[0315] In the formula (tR), R a , R b and R c Each independently represents an alkyl group having 1 to 24 carbon atoms, or one or two or more non-adjacent alkyl groups having 1 to 24 carbon atoms that are not terminal CH 3 -CH 2 - A group substituted with -O-. In the group represented by the formula (tR), * is the bonding position.

[0316] As R a , R b and R c The "alkyl group having 1 to 24 carbon atoms" may be any of a straight chain and a branched chain, and examples thereof include a straight chain alkyl group having 1 to 24 carbon atoms or a branched chain alkyl group having 3 to 24 carbon atoms, an alkyl group having 1 to 18 carbon atoms (a branched chain alkyl group having 3 to 18 carbon atoms), an alkyl group having 1 to 12 carbon atoms (a branched chain alkyl group having 3 to 12 carbon atoms), an alkyl group having 1 to 6 carbon atoms (a branched chain alkyl group having 3 to 6 carbon atoms), and an alkyl group having 1 to 4 carbon atoms (a branched chain alkyl group having 3 to 4 carbon atoms).

[0317] R in the formula (tR) a , R b and R c The total number of carbon atoms in the moiety is preferably 3 to 20, particularly preferably 3 to 10.

[0318] As R a , R b and Rc Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, tert-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, and n-icosyl.

[0319] Examples of the group represented by the formula (tR) include a tert-butyl group, a tert-amyl group, a 1-ethyl-1-methylpropyl group, a 1,1-diethylpropyl group, a 1,1-dimethylbutyl group, a 1-ethyl-1-methylbutyl group, a 1,1,3,3-tetramethylbutyl group, a 1,1,4-trimethylpentyl group, a 1,1,2-trimethylpropyl group, a 1,1-dimethyloctyl group, a 1,1-dimethylpentyl group, a 1,1-dimethylheptyl group, a 1,1,5-trimethylhexyl group, 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, tert-butyl and tert-pentyl are preferred.

[0320] As the substituent, a substituent represented by formula (A30) is also preferred.

[0321] The emission wavelength can be adjusted by the steric hindrance, electron donating property, and electron withdrawing property of the structure of the substituent possessed by the compound used as a dopant (assisting dopant or emitting dopant). The group represented by the following structural formula is preferred, and a methyl group, a tert-butyl group, a tert-amyl group, a tert-octyl group, a neopentyl group, an adamantyl group, a phenyl group, an o-tolyl group, a p-tolyl group, a 2,4-xylyl group, a 2,5-xylyl group, a 2,6-xylyl group, a 2,4,6-mesityl group, a diphenylamino group, a di-p-tolylamino group, a bis(p-(tert-butyl)phenyl)amino group, a carbazolyl group, a 3,6-dimethylcarbazolyl group, a 3,6-di-tert-butylcarbazolyl group, and a phenoxy group are more preferred. A methyl group, a tert-butyl group, a tert-amyl group, a tert-octyl group, a neopentyl group, an adamantyl group, a phenyl group, an o-tolyl group, a 2,6-xylyl group, a 2,4,6-mesityl group, a diphenylamino group, a di-p-tolylamino group, a bis(p-(tert-butyl)phenyl)amino group, a carbazolyl group, a 3,6-dimethylcarbazolyl group, a 3,6-di-tert-butylcarbazolyl group, and a tribenzazepinyl group are further preferred. From the viewpoint of ease of synthesis, a group with large steric hindrance is preferred because selective synthesis can be performed. Specifically, a tert-butyl group, a tert-amyl group, a tert-octyl group, an adamantyl group, an o-tolyl group, a p-tolyl group, a 2,4-xylyl group, a 2,5-xylyl group, a 2,6-xylyl group, a 2,4,6-mesityl group, a di-p-tolylamino group, a bis(p-(tert-butyl)phenyl)amino group, a 3,6-dimethylcarbazolyl group, and a 3,6-di-tert-butylcarbazolyl group are preferred.

[0322] In the following structural formulas, * indicates a bonding position.

[0323] [Chemistry 32]

[0324]

[0325] [Chemistry 33]

[0326]

[0327] [Chemistry 34]

[0328]

[0329] [Chemistry 35]

[0330]

[0331] [Chemistry 36]

[0332]

[0333] [Chemistry 37]

[0334]

[0335] [Chemistry 38]

[0336]

[0337] [Chemistry 39]

[0338]

[0339] [Chemistry 40]

[0340]

[0341] [Chemistry 41]

[0342]

[0343] [Chemistry 42]

[0344]

[0345] [Chemistry 43]

[0346]

[0347] [Chemistry 44]

[0348]

[0349] [Chemistry 45]

[0350]

[0351] The polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1) is preferably a structure comprising at least one tertiary alkyl group (tert-butyl or tert-amyl, etc.), neopentyl or adamantyl represented by the formula (tR), and more preferably a tertiary alkyl group (tert-butyl or tert-amyl, etc.) represented by the formula (tR). The reason is that the intermolecular distance is increased by such a bulky substituent, so the luminescence quantum yield (PLQY) is improved. In addition, as a substituent, a diarylamino group is also preferred. Furthermore, a diarylamino group substituted by a base of formula (tR), a carbazolyl group substituted by a base of formula (tR) (preferably N-carbazolyl) or a benzocarbazolyl group substituted by a base of formula (tR) (preferably N-benzocarbazolyl) is also preferred. As a substitution form of the base of formula (tR) for diarylamino, carbazolyl and benzocarbazolyl, examples of hydrogen substitution of part or all of the hydrogen of the aryl ring or benzene ring in these groups by the base of formula (tR) can be cited.

[0352] In the structure composed of one or more structural units represented by formula (1), the substituent of the aryl ring or heteroaryl ring may be a substituent represented by the following formula (A20).

[0353] [Chemistry 46]

[0354]

[0355] The substituent represented by formula (A20) is bonded to two adjacent atoms on the aryl ring or heteroaryl ring at two * positions. In formula (A20), L is >NR, >O, >Si(-R) 2 or>S, wherein R of the>NR is a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl, or a substituted or unsubstituted cycloalkyl, and the>Si(-R) 2 R is hydrogen, aryl which may be substituted, alkyl which may be substituted, or cycloalkyl which may be substituted, and may be bonded to each other via a linking group. In addition, the >NR and the >Si(-R) 2 At least one of the R's may be bonded to the aryl ring or heteroaryl ring via a linking group or a single bond,

[0356] r is an integer from 1 to 4,

[0357] R A are independently hydrogen, substituted or unsubstituted alkyl or substituted or unsubstituted cycloalkyl, any R A Can be connected to any other R through a linking group or a single bond A Mutually bonded.

[0358] Examples of the substituent include substituents represented by any of the following.

[0359] [Chemistry 47]

[0360]

[0361] In each formula, the * only needs to be bonded to two or three consecutive (adjacent) atoms on any aryl ring or heteroaryl ring.

[0362] <Cycloalkane condensation>

[0363] In the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1), at least one selected from the group consisting of an aryl ring and a heteroaryl ring may be condensed with at least one cycloalkane. The same is true for the polycyclic aromatic compound represented by formula (1-A), formula (1-B), formula (1-C) or formula (1-D), and the following description is also applicable to the polycyclic aromatic compound represented by formula (1-A), formula (1-B), formula (1-C) or formula (1-D).

[0364] The cycloalkane may be a cycloalkane having 3 to 24 carbon atoms. At least one hydrogen atom in the cycloalkane may be substituted by an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, an alkyl group having 1 to 24 carbon atoms, or a cycloalkyl group having 3 to 24 carbon atoms. 2 - may be substituted by -O-.

[0365] The cycloalkane is preferably a cycloalkane having 3 to 20 carbon atoms, wherein at least one hydrogen in the cycloalkane may be substituted by an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 22 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 16 carbon atoms.

[0366] Examples of the “cycloalkane” include cycloalkanes having 3 to 24 carbon atoms, cycloalkanes having 3 to 20 carbon atoms, cycloalkanes having 3 to 16 carbon atoms, cycloalkanes having 3 to 14 carbon atoms, cycloalkanes having 5 to 10 carbon atoms, cycloalkanes having 5 to 8 carbon atoms, cycloalkanes having 5 to 6 carbon atoms, and cycloalkanes having 5 carbon atoms.

[0367] Specific examples of cycloalkanes include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornane (bicyclo[2.2.1]heptane), bicyclo[1.1.0]butane, bicyclo[1.1.1]pentane, bicyclo[2.1.0]pentane, bicyclo[2.1.1]hexane, bicyclo[3.1.0]hexane, bicyclo[2.2.2]octane, adamantane, diadamantane, decahydronaphthalene and decahydroazulene, and alkyl (especially methyl)-substituted, halogen (especially fluorine)-substituted and deuterium-substituted products thereof having 1 to 5 carbon atoms.

[0368] Among the examples, a structure having at least one substituent on the carbon at the α position of the cycloalkane (a carbon adjacent to the carbon at the condensation site in the cycloalkane condensed to an aryl ring or a heteroaryl ring) such as shown in the following structural formula is preferred, a structure having two substituents on the carbon at the α position is more preferred, and a structure having two substituents on both carbons at the α position is further preferred (having a total of four substituents). As the substituent, alkyl groups (especially methyl) having 1 to 5 carbon atoms, halogens (especially fluorine) and deuterium are listed. Particularly preferred is a structure in which a partial structure represented by the following formula (B11) or the following formula (B12) is bonded to adjacent carbon atoms in an aryl ring or a heteroaryl ring, and more preferred is a structure in which a partial structure represented by the following formula (B11) is bonded to adjacent carbon atoms in an aryl ring or a heteroaryl ring.

[0369] [Chemistry 48]

[0370]

[0371] In each of formula (B11) and formula (B12), * represents a bonding position.

[0372] The number of cycloalkanes condensed on one aryl ring or heteroaryl ring is preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. For example, the following shows an example in which one or more cycloalkanes are condensed on a benzene ring (phenyl). * represents the bonding position, which can be any of the carbons that constitute the benzene ring and do not constitute the cycloalkane. The cycloalkanes condensed as in formula (Cy-1-4) and formula (Cy-2-4) can also be condensed with each other. This is true whether the condensed ring (base) is an aryl ring or heteroaryl ring other than the benzene ring (phenyl), or whether the condensed cycloalkane is a cycloalkane other than cyclopentane or cyclohexane.

[0373] [Chemistry 49]

[0374]

[0375] At least one -CH 2 - may be substituted by -O-. For example, the following shows one or more -CH in a cycloalkane condensed on a benzene ring (phenyl): 2 The same applies whether the ring (group) to be condensed is an aryl ring or a heteroaryl ring other than the benzene ring (phenyl), or whether the cycloalkane to be condensed is a cycloalkane other than cyclopentane or cyclohexane.

[0376] [Chemistry 50]

[0377]

[0378] The cycloalkane may be substituted with at least one substituent, and as the substituent, any substituent selected from the substituent group Z can be cited. Among these substituents, alkyl groups (e.g., alkyl groups having 1 to 6 carbon atoms) and cycloalkyl groups (e.g., cycloalkyl groups having 3 to 14 carbon atoms) are preferred. In addition, it is also preferred that any hydrogen group is substituted with a halogen (e.g., fluorine) or deuterium. In addition, when a cycloalkyl group is substituted, it may be a substitution form that forms a spiro ring structure. For example, the following shows an example in which a spiro ring structure is formed in a cycloalkane condensed on a benzene ring (phenyl). Regarding the * in each structural formula, in the case of a benzene ring, it refers to a benzene ring contained in the skeletal structure of the compound, and in the case of a phenyl group, it refers to a bond that is substituted in the skeletal structure of the compound.

[0379] [Chemistry 51]

[0380]

[0381] Examples of the cycloalkane condensation include: a form in which an aryl ring or heteroaryl ring in the A ring, B ring, C ring, D ring, or E ring of a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) is condensed with a cycloalkane; a form in which an aryl ring or heteroaryl ring in Ar (a monovalent group represented by formula (Ar) or the like) is condensed with a cycloalkane; and a form in which an aryl ring or heteroaryl ring is condensed with a cycloalkane when any of the other substituents is a group containing an aryl ring or a heteroaryl ring.

[0382] In addition, by introducing a cycloalkane structure into a polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1), a further reduction in the melting point or sublimation temperature can be expected. The situation means that in the sublimation purification, which is almost indispensable as a purification method for organic devices such as organic EL elements requiring high purity, since the purification can be carried out at a lower temperature, the thermal decomposition of the material can be avoided. In addition, the situation is also the same for the vacuum evaporation process, which is a powerful means for making organic devices such as organic EL elements. The process can be implemented at a lower temperature, so the thermal decomposition of the material can be avoided, and a high-performance organic device can be obtained as a result. In addition, since the solubility in the organic solvent is improved by introducing the cycloalkane structure, it can also be applied to the production of components using a coating process. Among them, the present invention is not particularly limited to these principles.

[0383] <Substitution with heavy stable isotopes>

[0384] Each element in the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) is an element containing multiple naturally occurring isotopes in a naturally occurring ratio unless otherwise specified. Among them, all or part of the elements in each structural formula may also contain a heavy stable isotope exceeding the naturally occurring ratio (for example, 90 atomic % (atom %) or more in boron-11 (11B)). In this specification, it is simply referred to as "substituted with" or "heavy stable isotope". More specifically, at least one hydrogen can be substituted with deuterium, at least one nitrogen can be substituted with nitrogen-15 (15N), at least one sulfur can be substituted with sulfur-33 (33S), sulfur-34 (34S) or sulfur-36 (36S), at least one oxygen can be substituted with oxygen-17 (17O) or oxygen-18 (18O), at least one carbon can be substituted with carbon-13 (13C), and at least one boron can be substituted with boron-11 (11B). The same is true for the polycyclic aromatic compounds represented by formula (1-A), formula (1-B), formula (1-C) or formula (1-D), and this description is also applicable to these polycyclic aromatic compounds. By replacing at least a part of the elements with heavy stable isotopes, especially by replacing at least one boron with boron-11 (11B), the life of an organic electroluminescent element using a polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) can be extended.

[0385] <Substitution using deuterium>

[0386] Regarding the hydrogen in the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1), all or part of them may be deuterium. The same is true for the polycyclic aromatic compounds represented by formula (1-A), formula (1-B), formula (1-C) or formula (1-D), and the following description is also applicable to these polycyclic aromatic compounds.

[0387] For example, hydrogen in any of the A ring, B ring, C ring, D ring, E ring, and Ar in the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) may be substituted with deuterium, and among these, all or part of the hydrogen in the aryl or heteroaryl group may be substituted with deuterium. In addition, from the viewpoint of durability, it is also preferred that all or part of the hydrogen in the polycyclic aromatic compound having a structure composed of one or more structural units represented by formula (1) is deuterated.

[0388] <Specific examples of polycyclic aromatic compounds>

[0389] Specific examples of the polycyclic aromatic compound having a structure composed of one or two or more structural units represented by formula (1) include any of the following compounds.

[0390] [Chemistry 52]

[0391]

[0392] [Chemistry 53]

[0393]

[0394] [Chemistry 54]

[0395]

[0396] [Chemistry 55]

[0397]

[0398] [Chemistry 56]

[0399]

[0400] [Chemistry 57]

[0401]

[0402] [Chemistry 58]

[0403]

[0404] [Chemistry 59]

[0405]

[0406] [Chemistry 60]

[0407]

[0408] [Chemistry 61]

[0409]

[0410] [Chemistry 62]

[0411]

[0412] [Chemistry 63]

[0413]

[0414] [Chemistry 64]

[0415]

[0416] [Chemistry 65]

[0417]

[0418] [Chemistry 66]

[0419]

[0420] [Chemistry 67]

[0421]

[0422] [Chemistry 68]

[0423]

[0424] [Chemistry 69]

[0425]

[0426] [Chemistry 70]

[0427]

[0428] [Chemistry 71]

[0429]

[0430] [Chemistry 72]

[0431]

[0432] [Chemistry 73]

[0433]

[0434] [Chemistry 74]

[0435]

[0436] [Chemistry 75]

[0437]

[0438] [Chemistry 76]

[0439]

[0440] [Chemistry 77]

[0441]

[0442] [Chemistry 78]

[0443]

[0444] [Chemistry 79]

[0445]

[0446] [Chemistry 80]

[0447]

[0448] [Chemistry 81]

[0449]

[0450] [Chemistry 82]

[0451]

[0452] [Chemistry 83]

[0453]

[0454] [Chemistry 84]

[0455]

[0456] [Chemistry 85]

[0457]

[0458] [Chemistry 86]

[0459]

[0460] [Chemistry 87]

[0461]

[0462] [Chemistry 88]

[0463]

[0464] [Chemistry 89]

[0465]

[0466] [Chemistry 90]

[0467]

[0468] [Chemistry 91]

[0469]

[0470] [Chemistry 92]

[0471]

[0472] [Chemistry 93]

[0473]

[0474] [Chemistry 94]

[0475]

[0476] [Chemistry 95]

[0477]

[0478] [Chemistry 96]

[0479]

[0480] [Chemistry 97]

[0481]

[0482] [Chemistry 98]

[0483]

[0484] [Chemistry 99]

[0485]

[0486] [Chemical 100]

[0487]

[0488] [Chemistry 101]

[0489]

[0490] [Chemistry 102]

[0491]

[0492] [Chemistry 103]

[0493]

[0494] [Chemistry 104]

[0495]

[0496] [Chemistry 105]

[0497]

[0498] [Chemistry 106]

[0499]

[0500] [Chemistry 107]

[0501]

[0502] [Chemistry 108]

[0503]

[0504] [Chemistry 109]

[0505]

[0506] [Chemistry 110]

[0507]

[0508] [Chemistry 111]

[0509]

[0510] [Chemistry 112]

[0511]

[0512] [Chemistry 113]

[0513]

[0514] [Chemistry 114]

[0515]

[0516] [Chemistry 115]

[0517]

[0518] [Chemistry 116]

[0519]

[0520] [Chemistry 117]

[0521]

[0522] [Chemistry 118]

[0523]

[0524] [Chemistry 119]

[0525]

[0526] [Chemistry 120]

[0527]

[0528] [Chemistry 121]

[0529]

[0530] [Chemistry 122]

[0531]

[0532] [Chemistry 123]

[0533]

[0534] [Chemistry 124]

[0535]

[0536] [Chemistry 125]

[0537]

[0538] [Chemistry 126]

[0539]

[0540] [Chemistry 127]

[0541]

[0542] <Application of polycyclic aromatic compounds in polymers>

[0543] The polycyclic aromatic compound of the present invention can also be used in materials for organic devices, such as materials for organic electroluminescent elements, materials for organic field effect transistors, materials for organic thin-film solar cells, or wavelength conversion filters, as the following polymer compound (the monomer used to obtain the polymer compound has a polymerizable substituent), or a polymer crosslinked body (the polymer compound used to obtain the polymer crosslinked body has a crosslinkable substituent), or the following pendant polymer compound (the reactive compound used to obtain the pendant polymer compound has a reactive substituent), or a pendant polymer crosslinked body (the pendant polymer compound used to obtain the pendant polymer crosslinked body has a crosslinkable substituent), wherein the polymer compound is obtained by polymerizing the reactive compound substituted with a reactive substituent in the polycyclic aromatic compound of the present invention as a monomer, the polymer crosslinked body is obtained by further crosslinking the polymer compound, the pendant polymer compound is obtained by reacting a main chain polymer with the reactive compound, and the pendant polymer crosslinked body is obtained by further crosslinking the pendant polymer compound.

[0544] The reactive substituent (including the polymerizable substituent, the cross-linkable substituent, and the reactive substituent for obtaining the pendant type polymer, hereinafter also referred to as "reactive substituent") is not particularly limited as long as it is a substituent that can make the polycyclic aromatic compound high molecular weight, a substituent that can further cross-link the polymer compound obtained in this way, and a substituent that can undergo a pendant reaction in the main chain type polymer, but preferably a substituent of the following structure. * in each structural formula represents a bonding position.

[0545] [Chemistry 128]

[0546]

[0547] Z is independently a single bond, -O-, -S-, >C=O, -OC(=O)-, an alkylene group having 1 to 12 carbon atoms, an oxyalkylene group having 1 to 12 carbon atoms, and a polyoxyalkylene group having 1 to 12 carbon atoms. Among the substituents, a group represented by formula (XLS-1), formula (XLS-2), formula (XLS-3), formula (XLS-9), formula (XLS-10), or formula (XLS-17) is preferred, and a group represented by formula (XLS-1), formula (XLS-3), or formula (XLS-17) is more preferred.

[0548] Such polymer compounds, polymer crosslinked bodies, pendant polymer compounds, and pendant polymer crosslinked bodies may contain, in addition to the repeating units of the polycyclic aromatic compounds of the present invention, at least one compound selected from the group consisting of substituted or unsubstituted triarylamines, substituted or unsubstituted fluorenes, substituted or unsubstituted anthracenes, substituted or unsubstituted tetracene, substituted or unsubstituted triazines, substituted or unsubstituted carbazoles, substituted or unsubstituted tetraphenylsilanes, substituted or unsubstituted spirofluorenes, substituted or unsubstituted triphenylphosphine, substituted or unsubstituted dibenzothiophene, and substituted or unsubstituted dibenzofurans as repeating units.

[0549] As the substituent in these repeating units, for example, at least one substituent selected from the substituent group Z can be mentioned.

[0550] <Method for producing polycyclic aromatic compounds>

[0551] The polycyclic aromatic compound having a structure composed of one or more of the structural units represented by formula (1) is basically firstly bonded by a bonding group (nitrogen) to ring A (a ring), ring B (b ring) and ring C (c ring), thereby producing an intermediate (first reaction), and then, by bonding ring A (a ring), ring B (b ring) and ring C (c ring) to ring B (b ring), thereby producing a final product (second reaction). In the first reaction, for example, if it is an etherification reaction, general reactions such as nucleophilic substitution reaction and Ullmann reaction can be used, and if it is an amination reaction, general reactions such as Buchwald-Hartwig reaction, nucleophilic substitution reaction and Goldberg amination can be used. In addition, in the second reaction, a tandem hetero-Friedel-Crafts reaction (continuous aromatic electrophilic substitution reaction, the same below) can be used. The target compound can be produced by using a raw material having a desired fused ring at a certain point in the reaction process or by adding a step of condensing the ring.

[0552] [Production method via intermediate 1]

[0553] 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 of International Publication No. 2015 / 102118.

[0554] The following is a reaction including the following reaction steps: synthesizing the following intermediate 1 from a halogenated precursor, reacting X in the following intermediate 1 with an organic base compound, 1 With X 2 and metallizing the halogen atom (Hal) between the metal and the boron; and exchanging the metal with the boron using a reagent selected from the group consisting of boron halides, boron amide halides, boron alkoxides, and boron aryloxides; and using a Brünster base to bond the b ring to the c ring by using the boron through a continuous aromatic electrophilic substitution reaction. The halogen atom (Hal) in the formula can be any one of F, Cl, Br, and I, and can be appropriately selected in consideration of the reactivity of the substrate.

[0555] [Chemistry 129]

[0556]

[0557] In addition, the above scheme (1) mainly shows the method for producing the polycyclic aromatic compound represented by the formula (1-A), but the compound represented by the formula (1-B) can also be produced in the same manner.

[0558] Examples of the metallating reagent used in the halogen-metal exchange reaction in the process described so far include alkyl lithiums such as methyl lithium, n-butyl lithium, sec-butyl lithium, and tert-butyl lithium, isopropyl magnesium chloride, isopropyl magnesium bromide, phenyl magnesium chloride, phenyl magnesium bromide, and a lithium chloride complex of isopropyl magnesium chloride known as Turbo Grignard reagent.

[0559] In addition, as the metallating reagent used in the ortho-metal exchange reaction in the process described so far, in addition to the above reagents, organic base compounds such as lithium diisopropylamide, lithium tetramethylpiperidinide, lithium hexamethyldisilazide, potassium hexamethyldisilazide, lithium chloride tetramethylpiperidinyl magnesium-lithium chloride complex, and tri-n-butyl lithium magnesiumate can also be listed.

[0560] Furthermore, examples of additives that promote the reaction when using alkyl lithium as the metallizing agent include N,N,N',N'-tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, and N,N-dimethylpropyleneurea.

[0561] In addition, examples of the Lewis acid used in the process described so far include: AlCl 3 , AlBr 3 , AlF 3 , BF 3 ·OEt 2 , BCl 3 , BBr 3 , BI 3 、GaCl 3 , GaBr 3 、InCl 3 、InBr 3 、In(OTf) 3 SnCl 4 SnBr 4 、AgOTf、ScCl 3 Sc(OTf) 3 、ZnCl 2 、ZnBr 2 、Zn(OTf) 2 MgCl 2 MgBr 2 、Mg(OTf) 2 、LiOTf、NaOTf、KOTf、Me 3 SiOTf, Cu(OTf) 2 , CuCl 2 , YCl 3 、Y(OTf) 3 、TiCl 4 、TiBr 4、ZrCl 4 , ZrBr 4 、FeCl 3 , FeBr 3 、CoCl 3 ,CoBr 3 Etc. In addition, those in which these Lewis acids are supported on a solid can also be used in the same manner.

[0562] In addition, examples of the Brønsted acid used in the process described so far include p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, fluorosulfonic acid, carboxylic acid, trifluoroacetic acid, (trifluoromethanesulfonyl)imide, tris(trifluoromethanesulfonyl)methane, hydrogen chloride, hydrogen bromide, hydrogen fluoride, etc. In addition, examples of solid Brønsted acid include Amberlist (trade name: Dow Chemical), Nafion (trade name: Dupont), zeolite, Taycacure (trade name: Tayca Co., Ltd.), etc.

[0563] In addition, examples of amines that can be added in the processes described above include diisopropylethylamine, triethylamine, tributylamine, 1,4-diazabicyclo[2.2.2]octane, N,N-dimethyl-p-toluidine, N,N-dimethylaniline, pyridine, 2,6-lutidine, and 2,6-di-tert-butylamine.

[0564] In addition, examples of the solvent used in the processes described so far include o-dichlorobenzene, chlorobenzene, toluene, benzene, dichloromethane, chloroform, dichloroethylene, benzotrifluoride, decahydronaphthalene, cyclohexane, hexane, heptane, 1,2,4-trimethylbenzene, xylene, diphenyl ether, anisole, cyclopentyl methyl ether, tetrahydrofuran, dioxane, and methyl-tert-butyl ether.

[0565] Here, Y is recorded 1 For example, Y can be synthesized by appropriately changing the raw materials. 1 It is a compound of P, P=O, P=S, Al, Ga, As, Si-R or Ge-R.

[0566] In the process, in order to promote the tandem hetero Friedel-Crafts reaction, a Brünster base or a Lewis acid may also be used. 1 trifluoride, Y 1 trichloride, Y 1 tribromide, Y 1 Triiodide, etc. 1In the case of halides, as the aromatic electrophilic substitution reaction proceeds, acids such as hydrogen fluoride, hydrogen chloride, hydrogen bromide, and hydrogen iodide are generated, so it is effective to use a Brünster base to capture the acid. 1 Amine halide, Y 1 In the case of alkoxylates, amines and alcohols are generated as the aromatic electrophilic substitution reaction proceeds, so in many cases, it is not necessary to use a Brünster base. However, since the amino group or alkoxy group has low ability to leave, it is effective to use a Lewis acid that promotes its leaving.

[0567] The polycyclic aromatic compound of the present invention also includes compounds in which at least a portion of hydrogen is substituted with deuterium or with various substituents, and such compounds can be synthesized in the same manner as above by using raw materials deuterated or derivatized at desired positions.

[0568] 2. Organic devices

[0569] The polycyclic aromatic compound of the present invention can be used as a material for organic devices. Examples of organic devices include organic electroluminescent elements, organic field effect transistors, and organic thin-film solar cells. 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 element.

[0570] 2-1. Organic electroluminescent element

[0571] 2-1-1. Structure of organic electroluminescent element

[0572] Figure 1 This is a schematic cross-sectional view showing an example of an organic EL element.

[0573] Figure 1 The organic EL element 100 shown includes: a substrate 101, an anode 102 arranged on the substrate 101, a hole injection layer 103 arranged on the anode 102, a hole transport layer 104 arranged on the hole injection layer 103, a light-emitting layer 105 arranged on the hole transport layer 104, an electron transport layer 106 arranged on the light-emitting layer 105, an electron injection layer 107 arranged on the electron transport layer 106, and a cathode 108 arranged on the electron injection layer 107.

[0574] In addition, the organic EL element 100 can also reverse the production order to form a structure such as the following, which includes: a substrate 101, a cathode 108 disposed on the substrate 101, an electron injection layer 107 disposed on the cathode 108, an electron transport layer 106 disposed on the electron injection layer 107, a light-emitting layer 105 disposed on the electron transport layer 106, a hole transport layer 104 disposed on the light-emitting layer 105, a hole injection layer 103 disposed on the hole transport layer 104, and an anode 102 disposed on the hole injection layer 103.

[0575] The above-mentioned layers are not all indispensable layers, and the minimum structural unit is set to a structure including 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 layers that can be arbitrarily provided. In addition, the above-mentioned layers may each include a single layer or a plurality of layers.

[0576] The morphology of the layers constituting the organic EL element may be, in addition to the structural morphology of “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / luminescent layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / luminescent layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron injection layer / cathode”. The structural morphology of the 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 injection layer / cathode", "substrate / anode / hole injection 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", and "substrate / anode / light-emitting layer / electron injection layer / cathode".

[0577] The organic EL element may further have any one or both selected from an electron blocking layer (electron blocking layer) and a hole blocking layer (hole blocking layer). The electron blocking layer has a LUMO that is shallower than the light-emitting layer and a HOMO that is close to the light-emitting layer or the hole transport layer, and is arranged between the light-emitting layer and the hole transport layer. Since the electrons are retained in the light-emitting layer and do not leak out to the hole transport layer, the shortening of the life caused by the degradation of the hole transport layer and the reduction in efficiency caused by the reduction in recombination efficiency can be prevented. The hole blocking layer has a HOMO that is deeper than the light-emitting layer and a LUMO that is close to the light-emitting layer or the hole transport layer, and is arranged between the light-emitting layer and the electron transport layer. Since the holes are retained in the light-emitting layer and do not leak out to the electron transport layer, the shortening of the life caused by the degradation of the electron transport layer and the reduction in efficiency caused by the reduction in recombination efficiency can be prevented. The hole injection / transport layer may also serve as an electron blocking layer. The electron injection / transport layer may also serve as a hole blocking layer.

[0578] The organic EL element may further have a high T1 layer. The high T1 layer has a higher T1 than the main compound, auxiliary dopant compound or emission dopant compound used in the light-emitting layer, and is arranged between the light-emitting layer and the hole transport layer and / or between the light-emitting layer and the electron blocking layer. The value of T1 energy varies depending on the light-emitting mechanism of the element, but has a higher T1 than the compound used in the main body. By having a high T1 layer around the light-emitting layer, triplet energy can be enclosed, and the triplet energy that is usually unrelated to light emission in the fluorescent molecules can be converted into singlet energy, thereby obtaining high efficiency. The hole injection / transport layer or the electron blocking layer can also serve as the high T1 layer. The electron injection / transport layer or the hole blocking layer can also serve as the high T1 layer.

[0579] The polycyclic aromatic compound of the present invention is preferably used as a material for forming a light-emitting layer or a material for forming an electron transport layer, and is more preferably used as a material for forming a light-emitting layer.

[0580] 2-1-2. Substrate in organic electroluminescent element

[0581] The substrate 101 is a support of the organic EL element 100, and quartz, glass, metal, plastic, etc. can be generally used. The substrate 101 is formed into a plate, film, or sheet according to the purpose, for example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, etc. can be used. Among them, glass plates and plates made of transparent synthetic resins such as polyester, polymethacrylate, polycarbonate, and polysulfone are preferred. If it is a glass substrate, soda-lime glass or alkali-free glass can be used, and the thickness can be sufficient to maintain mechanical strength. For example, it only needs to be 0.2 mm or more. As the upper limit of the thickness, for example, it is less than 2 mm, preferably less than 1 mm. Regarding the material of the glass, since the dissolved ions from the glass are preferably small, alkali-free glass is preferred. Since SiO 2Soda lime glass with a barrier coat such as , is also commercially available, so the soda lime glass can be used. In addition, in order to improve the gas barrier property, a gas barrier film such as a fine silicon oxide film can also be provided on at least one side of the substrate 101. When a plate, film or sheet made of a synthetic resin with low gas barrier property is used as the substrate 101, it is particularly preferred to provide a gas barrier film.

[0582] 2-1-3. Anode in organic electroluminescent element

[0583] The anode 102 plays a role of injecting holes into the light-emitting layer 105. When at least one of the hole injection layer 103 and the hole transport layer 104 is provided between the anode 102 and the light-emitting layer 105, holes are injected into the light-emitting layer 105 through these layers.

[0584] As materials for forming the anode 102, inorganic compounds and organic compounds can be cited. As inorganic compounds, for example, metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (Indium Tin Oxide, ITO), indium-zinc oxide (Indium Zinc Oxide, IZO), etc.), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass or Nesa glass, etc. As organic compounds, for example, polythiophenes such as poly(3-methylthiophene), conductive polymers such as polypyrrole and polyaniline, etc. can be cited. In addition, it can be appropriately selected from the substances used as the anode of the organic EL element for use.

[0585] 2-1-4. Hole injection layer and hole transport layer in organic electroluminescent element

[0586] The hole injection layer 103 plays a role of efficiently injecting holes migrated from the anode 102 into the light-emitting layer 105 or the hole transport layer 104. The hole transport layer 104 plays a role of efficiently transporting holes injected from the anode 102 or holes injected from the anode 102 via the hole injection layer 103 to the light-emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are formed by stacking or mixing one or more hole injection / transport materials. In addition, an inorganic salt such as iron (III) chloride can be added to the hole injection / transport material to form a layer.

[0587] As a hole injection / transport material, it is necessary to efficiently inject / transmit holes from the positive electrode between electrodes to which an electric field is applied, and it is ideal that the hole injection efficiency is high and the injected holes are efficiently transmitted. Therefore, it is preferred that the material has a small ionization potential, a large hole mobility, and excellent stability, and is not prone to produce impurities that become traps during manufacture and use.

[0588] As materials for forming the hole injection layer 103 and the hole transport layer 104, any compound can be selected from compounds conventionally used as charge transport materials for holes in photoconductive materials, and known compounds used in hole injection layers and hole transport layers of p-type semiconductors and organic EL elements. Specific examples thereof include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis(N-arylcarbazole) or bis(N-alkylcarbazole), triarylamine derivatives (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-carbazole-3-yl)-[1,1'-biphenyl]-4,4'-diamine, N 4 ,N 4 ,N 4 ',N 4 '-tetrakis([1,1'-biphenyl]-4-yl-[1,1'-biphenyl]-4,4'-diamine, 4,4',4"-tris(3-methylphenyl(phenyl)amino)triphenylamine and other triphenylamine derivatives, starburst amine derivatives, etc.), stilbene derivatives, phthalocyanine derivatives (metal-free, copper phthalocyanine, etc.), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives or 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. Among polymer systems, polycarbonate or styrene derivatives, polyvinylcarbazole and polysilane having the above monomers on the side chain are preferred, but there is no particular limitation as long as it is a compound that can form a thin film required for the production of a light-emitting element and can inject holes from the anode and then transport holes.

[0589] In addition, it is also known that the conductivity of organic semiconductors is strongly affected by their doping. Such organic semiconductor matrix materials contain compounds with good electron donating properties or compounds with good electron accepting properties. In order to dope electron donating materials, strong electron acceptors such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinonedimethane (F4TCNQ) are known (for example, refer to the literature "M. Pfeiffer, A. Bayer, T. Fritz, K. Leo (M. Pfeiffer , A. Beyer, T. Fritz, K. Leo), "Applied Physics Letters (Appl. Phys. Lett.)", 73(22), 3202-3204 (1998)" and the reference "J. Blochwitz, M. Pfeiffer, T. Fritz, K. Leo (J. Blochwitz, M. Pfeiffer, T. Fritz, K. Leo), "Applied Physics Letters (Appl. Phys. Lett.)", 73(6), 729-731 (1998)"). These so-called holes are generated through the electron migration process of the electron-donating basic material (hole transport material). The conductivity of the basic material varies greatly depending on the number and mobility of the holes. As a host material having hole transport properties, for example, benzidine derivatives (N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)benzidine (N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)benzidine, TPD), starburst amine derivatives (4,4',4"-tris(N,N-diphenylamino)triphenylamine (4,4',4"-tris(N,N-diphenylamino)triphenylamine, TDATA), or specific metal phthalocyanines (especially zinc phthalocyanine (ZnPc), etc.) are known (Japanese Patent Publication No. 2005-167175).

[0590] The hole injection layer material and the hole transport layer material can also be used in the hole layer material as the following polymer compound or its polymer cross-linked product, or the following pendant polymer compound or its pendant polymer cross-linked product, wherein the polymer compound is obtained by polymerizing a reactive compound substituted with a reactive substituent in the hole injection layer material and the hole transport layer material as a monomer, and the pendant polymer compound is obtained by reacting a main chain polymer with the reactive compound.

[0591] 2-1-5. Light-emitting layer in organic electroluminescent element

[0592] The polycyclic aromatic compound of the present invention is preferably used as a material for forming one or more organic layers in an organic electroluminescent element, and is more preferably used as a material for forming a light-emitting layer.

[0593] The light-emitting layer 105 is a layer that emits light by allowing holes injected from the anode 102 to recombine with electrons injected from the cathode 108 between electrodes to which an electric field is applied. The material forming the light-emitting layer 105 can be any compound (luminescent compound) that emits light by being excited by the recombination of holes and electrons, and preferably a compound that can form a stable thin film shape and exhibits strong luminescence (fluorescence) efficiency in a solid state.

[0594] The light-emitting layer may be a single layer or may include multiple layers, either of which are acceptable and are each formed of a light-emitting layer material. When the light-emitting layer includes multiple layers, preferably any one layer includes the polycyclic aromatic compound of the present invention. The light-emitting layer is preferably a single layer.

[0595] The light-emitting layer is formed by materials for the light-emitting layer (main material, dopant material). The main material and the dopant material may be one kind or a combination of multiple kinds, either of which is acceptable. For example, as dopant materials, emitting dopants and auxiliary dopants can be used. In addition, the light-emitting layer is also preferably composed of an emitting dopant and at least two selected from the group consisting of a hole-transporting main material, an electron-transporting main material and an auxiliary dopant material. The dopant material may be contained in the main material as a whole or in part of the main material, either of which is acceptable. As a doping method, it can be formed by co-evaporation with the main material, or it can be pre-mixed with the main material and evaporated simultaneously. In addition, the light-emitting layer can also be formed by a wet film-forming method using a light-emitting layer-forming composition prepared by dissolving a material in an organic solvent.

[0596] The amount of the host material used varies depending on the type of the host material, and can be determined by matching the characteristics of the host material. The basis for the amount of the host material used is preferably 50% to 99.999% by mass of the total mass of the material for the light-emitting layer, more preferably 80% to 99.95% by mass, and further preferably 90% to 99.9% by mass. In the case where the host material is a combination of a hole-transporting host material and an electron-transporting host material, the amount of the host material used is the mass of the hole-transporting host material and the electron-transporting host material added together. The ratio of the amount of the hole-transporting host material to the electron-transporting host material used can be 1:9 to 9:1 in terms of mass ratio, preferably 4:6 to 6:4, and more preferably approximately 1:1.

[0597] The amount of the emission dopant material used varies depending on the type of the emission dopant, and can be determined by matching its characteristics. The basis for the amount of the emission dopant material used is preferably 0.001% to 50% by mass of the total mass of the light-emitting layer material, more preferably 0.05% to 20% by mass, and further preferably 0.1% to 10% by mass. If it is within the above range, it is preferred, for example, in terms of preventing concentration quenching.

[0598] In an organic electroluminescent element that uses an auxiliary dopant (thermally active delayed phosphor or phosphorescent material) in addition to an emitting dopant, it is preferred that the emitting dopant material be used in a low concentration in order to prevent concentration quenching. In terms of the efficiency of energy migration, it is preferred that the auxiliary dopant material be used in a high concentration. In terms of the efficiency of the thermally active delayed fluorescence mechanism, it is preferred that the auxiliary dopant material be used in a high concentration. In an organic electroluminescent element that uses a thermally active delayed phosphor as an auxiliary dopant, it is preferred that the emitting dopant material be used in a low concentration compared to the amount of the auxiliary dopant material in terms of the efficiency of the thermally active delayed fluorescence mechanism of the auxiliary dopant.

[0599] When using auxiliary dopant materials, the base usage amounts of the main material, auxiliary dopant material and emission dopant material are 40% to 99% by mass, 59% to 1% by mass and 20% to 0.001% by mass, respectively, relative to the total mass of the materials for the light-emitting layer, preferably 60% to 95% by mass, 39% to 5% by mass and 10% to 0.01% by mass, respectively, and more preferably 70% to 90% by mass, 29% to 10% by mass and 5% to 0.05% by mass, respectively.

[0600] The polycyclic aromatic compound containing the structural unit represented by formula (1) is preferably used as a material for forming the light-emitting layer, more preferably used as a dopant, and particularly preferably used as an emissive dopant.

[0601] The polycyclic aromatic compound including the structural unit represented by the formula (1) can be used as an emitting dopant for a TTF device utilizing a phenomenon in which a singlet exciton is generated from a plurality of triplet excitons (Triplet-Triplet Fusion (TTF)).

[0602] In addition, a polycyclic aromatic compound containing a structural unit represented by formula (1) can be used as an emitting dopant of a TADF element as a "thermally active delayed phosphor". In a "thermally active delayed phosphor", by reducing the energy difference between the lowest excited singlet state and the lowest excited triplet state, an inverse intersystem crossing from the lowest excited triplet state to the lowest excited singlet state, which usually has a low transition probability, is efficiently generated, thereby showing luminescence from the singlet state (thermally active delayed fluorescence, TADF). In normal fluorescent luminescence, 75% of the triplet excitons generated by current excitation pass through the thermal deactivation path and therefore cannot be extracted as fluorescence. On the other hand, in TADF, all excitons can be used for fluorescent luminescence, which can achieve a highly efficient organic EL element.

[0603] It is generally believed that the case of fast delayed fluorescence has excellent TADF properties. Specifically, when a light-emitting material with a delayed fluorescence lifetime of 100 μsec or less is used as an emission dopant in a light-emitting element, high element efficiency and long element lifetime can be provided. The delayed fluorescence lifetime is preferably 20 μsec or less, more preferably less than 20 μsec, further preferably 10 μsec or less, and most preferably 5 μsec or less.

[0604] In addition, generally speaking, ΔE S1T1 The smaller the value of, the better the TADF property. S1T1 is the lowest excited singlet energy level (E S1 ) and the lowest excited triplet energy level (E T1 ) energy difference. Specifically, ΔE S1T1 The value of is preferably 0.20 eV or less, more preferably 0.15 eV or less, and particularly preferably 0.10 eV or less.

[0605] <Main material>

[0606] Examples of the host material include condensed ring derivatives of anthracene or pyrene, which have been known as luminescent materials in the past, bistyryl derivatives such as bistyryl anthracene derivatives and distyryl benzene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, fluorene derivatives, benzofluorene derivatives, N-phenylcarbazole derivatives, carbazole nitrile derivatives, dibenzo[pi] Derivatives, etc. In addition, from the viewpoint of durability, it is also preferred that part or all of the hydrogen atoms of the host material are deuterated. Furthermore, it is also preferred that a host compound in which part or all of the hydrogen atoms are deuterated is combined with a dopant compound in which part or all of the hydrogen atoms are deuterated to form a light-emitting layer.

[0607] The host material may be one kind or a combination of two or more kinds. In the case of a combination of two or more kinds, a combination of a hole-transporting host material and an electron-transporting host material is preferred.

[0608] [Anthracene compounds]

[0609] Examples of the main anthracene compound include compounds represented by formula (3-H) and compounds represented by formula (3-H2).

[0610] [Chemistry 130]

[0611]

[0612] In formula (3-H),

[0613] X and Ar 4 are each independently hydrogen or selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diarylamino, optionally substituted diheteroarylamino, substituted or unsubstituted arylheteroarylamino, substituted or unsubstituted alkyl, optionally substituted cycloalkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted arylthio or substituted silyl, all of X and Ar 4 It will not become hydrogen at the same time.

[0614] At least one hydrogen in the compound represented by formula (3-H) may be substituted by a halogen, a cyano group, a deuterium group or an optionally substituted heteroaryl group.

[0615] In addition, the structure represented by formula (3-H) can also be used as a unit structure to form a polymer (preferably a dimer). In the above case, for example, the unit structures represented by formula (3-H) are bonded to each other via X, and as the X, a single bond, an arylene group (phenylene, biphenylene and naphthylene, etc.) and a heteroarylene group (pyridine ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, benzocarbazole ring and phenyl-substituted carbazole ring, etc., having a divalent bonding valence) can be listed.

[0616] The details of each group in the compound represented by formula (3-H) can be referred to the description of formula (1) above, and will be further described in the following preferred embodiment.

[0617] Preferred embodiments of the anthracene compound are described below. The definitions of the symbols in the following structures are the same as those described above.

[0618] [Chemistry 131]

[0619]

[0620] In formula (3-H), 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 are not simultaneously represented by formula (3-X3). More preferably, two Xs are not simultaneously represented by formula (3-X2).

[0621] In addition, the structure represented by formula (3-H) can also be used as a unit structure to form a polymer (preferably a dimer). In the above case, for example, the unit structures represented by formula (3-H) are bonded to each other via X, and as the X, a single bond, an arylene group (phenylene, biphenylene and naphthylene, etc.) and a heteroarylene group (pyridine ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, benzocarbazole ring and phenyl-substituted carbazole ring, etc., having a divalent bonding valence) can be listed.

[0622] The naphthylene moiety in formula (3-X1) and formula (3-X2) can be condensed with one benzene ring. The structure formed by condensation in this manner is shown below.

[0623] [Chemistry 132]

[0624]

[0625] Ar 1 and Ar 2 are independently hydrogen, phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, phenyl, triphenylene, pyrene, or a group represented by formula (A) (including carbazolyl, benzocarbazolyl, and phenyl-substituted carbazolyl). 1 or Ar 2 In the case of a group represented by formula (A), the group represented by formula (A) is bonded to the naphthalene ring in formula (3-X1) or formula (3-X2) at the *.

[0626] Ar 3 is phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, phenyl, triphenylene, pyrene, or a group represented by formula (A) (including carbazolyl, benzocarbazolyl, and phenyl-substituted carbazolyl). 3 In the case of a group represented by formula (A), the group represented by formula (A) is bonded to the single bond represented by the straight line in formula (3-X3) at the *. That is, the anthracene ring of formula (3-H) is directly bonded to the group represented by formula (A).

[0627] In addition, Ar 3 It may have a substituent, Ar 3At least one hydrogen in the alkyl group may be replaced by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthrenyl group, a fluorenyl group, substituted with a phenyl group, a triphenylene group, a pyrene group, or a group represented by formula (A) (including a carbazolyl group and a phenyl-substituted carbazolyl group). 3 When the substituent is a group represented by formula (A), the group represented by formula (A) is in the position * and Ar in formula (3-X3) 3 Bond.

[0628] Ar 4 Each independently represents hydrogen, phenyl, biphenyl, terphenyl, naphthyl, or a silyl group substituted with an alkyl group having 1 to 4 carbon atoms (such as methyl, ethyl, and tert-butyl) and / or a cycloalkyl group having 5 to 10 carbon atoms.

[0629] Examples of the alkyl group having 1 to 4 carbon atoms substituting in the silyl group include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, and cyclobutyl. Three hydrogen atoms in the silyl group are independently substituted with these alkyl groups.

[0630] Specific examples of the “silyl group substituted with an alkyl group having 1 to 4 carbon atoms” include trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, tri-sec-butylsilyl, tri-tert-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, tert-butyldimethylsilyl, methyldiethylsilyl, propyldiethylsilyl, isopropyldiethylsilyl, butyldiethylsilyl, sec-butyldiethylsilyl, tert-butyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, tert-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, and tert-butyldiisopropylsilyl.

[0631] Examples of the cycloalkyl group having 5 to 10 carbon atoms which substitutes in the silyl group include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, bicyclo[1.1.1]pentyl, bicyclo[2.1.0]pentyl, bicyclo[2.1.1]hexyl, bicyclo[3.1.0]hexyl, bicyclo[2.2.1]heptyl (norbornyl), bicyclo[2.2.2]octyl, adamantyl, decahydronaphthyl, decahydroazulenyl, and the like, and the three hydrogen atoms in the silyl group are independently substituted by these cycloalkyl groups.

[0632] Specific examples of the "silyl group substituted with a cycloalkyl group having 5 to 10 carbon atoms" include a tricyclopentylsilyl group and a tricyclohexylsilyl group.

[0633] The substituted silyl group includes a dialkylcycloalkylsilyl group substituted with two alkyl groups and one cycloalkyl group, and an alkyldicycloalkylsilyl group substituted with one alkyl group and two cycloalkyl groups. Specific examples of the substituted alkyl group and cycloalkyl group include the groups described above.

[0634] In addition, the hydrogen in the chemical structure of the anthracene compound represented by formula (3-H) may also be replaced by a group represented by formula (A). In the case of replacement by a group represented by formula (A), the group represented by formula (A) replaces at least one hydrogen in the compound represented by formula (3-H) at the *.

[0635] The group represented by formula (A) is one of substituents that the anthracene compound represented by formula (3-H) may have.

[0636] [Chemistry 133]

[0637]

[0638] In formula (A), Y is -O-, -S- or >NR 29 , R 21 ~R 28 are each independently hydrogen, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted aryl group, an optionally substituted heteroaryl group, an optionally substituted alkoxy group, an optionally substituted aryloxy group, an optionally substituted arylthio group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group, an alkyldicycloalkylsilyl group, an optionally substituted amino group, a halogen group, a hydroxyl group or a cyano group, and R 21 ~R 28 The adjacent groups in the group may be bonded to each other to form a hydrocarbon ring, an aromatic ring or a heteroaromatic ring. 29 is hydrogen or an aryl group which may be substituted.

[0639] Y in formula (A) is preferably -O-.

[0640] R 21 ~R 28 The adjacent groups in can be bonded to each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring. The case where a ring is not formed is a group represented by the following formula (A-1). As the case where a ring is formed, for example, the groups represented by the following formulas (A-2) to (A-14) can be listed. In addition, at least one hydrogen in the group represented by any one of formulas (A-1) to (A-14) can be substituted by an alkyl, cycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, arylthio, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, diaryl (two aryl groups can be bonded to each other via a linking group) substituted amino, diheteroaryl substituted amino, arylheteroaryl substituted amino, halogen, hydroxyl or cyano.

[0641] [Chemistry 134]

[0642]

[0643] Examples of the ring formed by mutually bonding adjacent groups include a hydrocarbon ring such as a cyclohexane ring, and examples of the aryl ring or heteroaryl ring include the above R 21 ~R 28 The ring structure described in the "aryl" or "heteroaryl" in formula (A-1) is formed by condensing with one or two benzene rings.

[0644] The group represented by formula (A) is a group obtained by removing a hydrogen atom at any position of formula (A), and * represents the position. That is, the group represented by formula (A) can be bonded at any position. For example, it can be bonded to any carbon atom on the two benzene rings in the structure of formula (A), R 21 ~R 28 The atoms on any ring formed by bonding the adjacent groups in the formula (A) to each other, or the ">NR" as Y in the structure of the formula (A) 29 "R 29 Any position in or ">NR 29 "N(R 29 The same applies to the group represented by any one of the formulae (A-1) to (A-14).

[0645] As the group represented by formula (A), for example, a group represented by any one of formulas (A-1) to (A-14) can be listed, preferably a group represented by any one of formulas (A-1) to (A-5) and (A-12) to (A-14), more preferably a group represented by any one of formulas (A-1) to (A-4), further preferably a group represented by any one of formulas (A-1), (A-3) and (A-4), and particularly preferably a group represented by formula (A-1).

[0646] Examples of the group represented by formula (A) include the following groups: Y and * in the formula have the same meanings as described above.

[0647] [Chemistry 135]

[0648]

[0649] [Chemistry 136]

[0650]

[0651] In the compound represented by formula (3-H), the group represented by formula (A) is preferably in a naphthalene ring in formula (3-X1) or formula (3-X2), a single bond in formula (3-X3) and Ar in formula (3-X3).3 The form of any bond in .

[0652] In addition, all or part of the hydrogen atoms in the chemical structure of the anthracene compound represented by the formula (3-H) may be deuterium atoms.

[0653] The anthracene compound serving as a host may be, for example, a compound represented by the following formula (3-H2).

[0654] [Chemistry 137]

[0655]

[0656] In formula (3-H2), Ar c is an aryl group which may be substituted or a heteroaryl group which may be substituted, R c is hydrogen, alkyl, or cycloalkyl, Ar 11 ,Ar 12 ,Ar 13 ,Ar 14 ,Ar 15 , A 16 ,Ar 17 and Ar 18 Each of the above groups is independently hydrogen, a substitutable aryl, a substitutable heteroaryl, a substitutable diarylamino, a substitutable diheteroarylamino, a substitutable arylheteroarylamino, a substitutable alkyl, a substitutable cycloalkyl, a substitutable alkenyl, a substitutable alkoxy, a substitutable aryloxy, a substitutable arylthio, or a substitutable silanyl group, and at least one hydrogen in the compound represented by formula (3-H2) may be substituted by halogen, cyano, or deuterium.

[0657] The definitions of “substitutable aryl”, “substitutable heteroaryl”, “substitutable diarylamino”, “substitutable diheteroarylamino”, “substitutable arylheteroarylamino”, “substitutable alkyl”, “substitutable cycloalkyl”, “substitutable alkenyl”, “substitutable alkoxy”, “substitutable aryloxy”, “substitutable arylthio”, or “substitutable silyl” in formula (3-H2) are the same as those shown in formula (3-H), and the description in formula (3-H) can be cited.

[0658] The "aryl group which may be substituted" is preferably a group represented by any one of the following formulas (3-H2-X1) to (3-H2-X8).

[0659] [Chemistry 138]

[0660]

[0661] In formula (3-H2-X1) to formula (3-H2-X8), * represents a bonding position. In formula (3-H2-X1) to formula (3-H2-X3), Ar 21 ,Ar 22 and Ar 23 are independently hydrogen, phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, In the description of formula (3-H2), the group represented by formula (A) is the same as the group described in the anthracene compound represented by formula (3-H).

[0662] In formula (3-H2-X4) to formula (3-H2-X8), Ar 24 ,Ar 25 ,Ar 26 ,Ar 27 ,Ar 28 ,Ar 29 , and Ar 30 are independently hydrogen, phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, In addition, any one or two or more hydrogen atoms in each of the groups represented by formula (3-H2-X1) to formula (3-H2-X8) may be substituted by an alkyl group having 1 to 6 carbon atoms (preferably a methyl group or a tert-butyl group).

[0663] Furthermore, preferred examples of the "aryl group which may be substituted" include phenyl, biphenyl, terphenyl, naphthyl, phenanthrenyl, fluorenyl, A terphenyl group (particularly m-terphenyl-5′-group) substituted with one or more substituents selected from the group consisting of a terphenyl group, a triphenylene group, a pyrene group, and a group represented by formula (A).

[0664] Examples of the "optionally substituted heteroaryl group" include groups represented by formula (A). In addition, specific examples of the "optionally substituted aryl group" and the "optionally substituted heteroaryl group" include dibenzofuranyl, naphthobenzofuranyl, and phenyl-substituted dibenzofuranyl.

[0665] At least one hydrogen in the compound represented by formula (3-H2) may be substituted by halogen, cyano or deuterium. Examples of the "halogen" in the above case include fluorine, chlorine, bromine, and iodine. Particularly preferred are compounds in which all hydrogens in the compound represented by formula (3-H2) are substituted by deuterium.

[0666] In formula (3-H2), R c It is hydrogen, alkyl or cycloalkyl, preferably hydrogen, methyl or tert-butyl, more preferably hydrogen.

[0667] In the formula (3-H2), Ar is preferably 11 ~Ar 18 At least two of them are substituted aryl groups or substituted heteroaryl groups. 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 substituted aryl groups and substituted heteroaryl groups are bonded to the anthracene ring.

[0668] Among the anthracene compounds represented by formula (3-H2), Ar 11 ~Ar 18 Two of the anthracene compounds are substituted aryl groups or substituted heteroaryl groups, and the other six are hydrogen, substituted alkyl groups, substituted cycloalkyl groups, substituted alkenyl groups or substituted alkoxy groups. That is, the anthracene compound represented by formula (3-H2) is more preferably a structure having three substituents selected from the group consisting of substituted aryl groups and substituted heteroaryl groups bonded to the anthracene ring.

[0669] Among the anthracene compounds represented by formula (3-H2), Ar 11 ~Ar 18 Any two of them are aryl or heteroaryl, and the other six are hydrogen, methyl or tert-butyl.

[0670] Furthermore, in the formula (3-H2), preferably R c is hydrogen, and Ar 11 ~Ar 18 Any six of them are hydrogen.

[0671] The anthracene compound represented by formula (3-H2) is preferably an anthracene compound represented by the following formula (3-H2-A), formula (3-H2-B), formula (3-H2-C), formula (3-H2-D), or formula (3-H2-E).

[0672] [Chemistry 139]

[0673]

[0674] In formula (3-H2-A), formula (3-H2-B), formula (3-H2-C), formula (3-H2-D) or formula (3-H2-E), Ar c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ' and Ar 18 'are independently phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, phenyl, triphenylene, pyrenyl, or a group represented by formula (A), at least one hydrogen in these groups may be replaced by phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, Here, when the hydrogen atoms of the methylene groups in the fluorenyl group and the benzofluorenyl group are substituted by phenyl groups, these phenyl groups may be bonded to each other via single bonds. c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ' and Ar 18 The carbon atom of the anthracene ring of ' may be bonded with a methyl group or a tert-butyl group in place of hydrogen.

[0675] When Ar c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ' and Ar 18 When ' and ' are respectively substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl, they are preferably a group represented by any one of the formulas (3-H2-X1) to (3-H2-X8).

[0676] Ar c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ' and Ar 18 'More preferably, they are independently phenyl, biphenyl (especially biphenyl-2-yl or biphenyl-4-yl), terphenyl (especially m-terphenyl-5'-yl), naphthyl, phenanthrenyl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4). In this case, at least one hydrogen in these groups may be substituted by a phenyl, biphenyl, naphthyl, phenanthrenyl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4).

[0677] In addition, at least one hydrogen in the compound represented by Formula (3-H2-A), Formula (3-H2-B), Formula (3-H2-C), Formula (3-H2-D) or Formula (3-H2-E) may be substituted by halogen, cyano, or deuterium. In addition, a deuterated form is preferred, and a form in which all anthracene rings are deuterated, or a form in which all hydrogen atoms are deuterated is preferred.

[0678] Particularly preferred anthracene compounds represented by the formula (3-H2) include anthracene compounds represented by the following formula (3-H2-Aa).

[0679] [Chemistry 140]

[0680]

[0681] In the formula (3-H2-Aa), Ar c '、Ar 14 ' and Ar 15 'are independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, A group represented by any one of the formulae (A-1) to (A-11), wherein at least one hydrogen in these groups may be replaced by a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, a benzofluorenyl group, Here, when the hydrogen atoms of the methylene groups in the fluorenyl group and the benzofluorenyl group are substituted by phenyl groups, these phenyl groups may be bonded to each other via single bonds. c '、Ar 14 ' and Ar 15 The carbon atom of the anthracene ring of ' may be substituted with a methyl group or a tert-butyl group instead of hydrogen. At least one hydrogen in the compound represented by formula (3-H2-Aa) may be substituted with a halogen or a cyano group, and at least one hydrogen in the compound represented by formula (3-H2-Aa) may be substituted with deuterium.

[0682] In the formula (3-H2-Aa), Ar c '、Ar 14 ' and Ar 15 'Preferably, they are independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4), and at least one hydrogen in these groups may be substituted by a phenyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4).

[0683] In the compound represented by the formula (3-H2-Aa), it is preferred that the carbon atom bonded to at least the 10-position of the anthracene ring (Ar c The hydrogen at the carbon to which the bond is attached is substituted with deuterium. That is, the compound represented by the formula (3-H2-Aa) is preferably a compound represented by the following formula (3-H2-Ab). In the formula (3-H2-Ab), D is deuterium, Ar c '、Ar 14 ' and Ar 15' is the same as the definition in formula (3-H2-Aa). D in formula (3-H2-Ab) means that at least the position is deuterated, and any one or more other hydrogens in formula (3-H2-Ab) may be deuterated at the same time, and it is also preferred that all hydrogens in formula (3-H2-Ab) are deuterated.

[0684] [Chemistry 141]

[0685]

[0686] Specific examples of anthracene compounds include compounds represented by formula (3-131-Y) to (3-182-Y), formula (3-183-N), formula (3-184-Y) to (3-284-Y), and compounds represented by formula (3-500) to (3-557), and formula (3-600) to (3-605), and formula (3-606-Y) to (3-626-Y). The hydrogen atoms in these formulas may be partially or completely substituted with deuterium, but particularly preferred forms of deuterium substitution are listed separately. Y in the formula may be -O-, -S-, >NR 29 (R 29 The definition is the same as above) or>C(-R 30 ) 2 (R 30 is any one of an aryl group or an alkyl group that can be linked, R 29 For example, phenyl, R 30 For example, methyl group. Regarding the formula number, for example, when Y is O, the formula (3-131-Y) is the formula (3-131-O), and when Y is -S- or >NR 29 In the case of, set it to formula (3-131-S) or formula (3-131-N) respectively.

[0687] [Chemistry 142]

[0688]

[0689] [Chemistry 143]

[0690]

[0691] [Chemistry 144]

[0692]

[0693] [Chemistry 145]

[0694]

[0695] [Chemistry 146]

[0696]

[0697] [Chemistry 147]

[0698]

[0699] [Chemistry 148]

[0700]

[0701] [Chemistry 149]

[0702]

[0703] [Chemistry 150]

[0704]

[0705] [Chemistry 151]

[0706]

[0707] [Chemistry 152]

[0708]

[0709] [Chemistry 153]

[0710]

[0711] [Chemistry 154]

[0712]

[0713] [Chemistry 155]

[0714]

[0715] [Chemistry 156]

[0716]

[0717] [Chemistry 157]

[0718]

[0719] [Chemistry 158]

[0720]

[0721] [Chemistry 159]

[0722]

[0723] [Chemistry 160]

[0724]

[0725] [Chemistry 161]

[0726]

[0727] In the above formula, D is deuterium.

[0728] Among these compounds, preferred are compounds of formula (3-131-Y) to (3-134-Y), formula (3-138-Y), formula (3-140-Y) to (3-143-Y), formula (3-150-Y), formula (3-153-Y) to (3-156-Y), formula (3-166-Y), formula (3-168-Y), formula (3-173-Y), formula (3-177-Y), formula (3-180-Y) to (3-183-N), formula (3-185-Y), formula (3-190-Y), formula (3-223-Y), formula (3-224-Y), -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). In addition, Y is preferably -O- or >NR 29 , more preferably -O-. In addition, a deuterium-substituted form is also preferred.

[0729] The anthracene compound may be a compound having a reactive group at a desired position of the anthracene skeleton, and in the case of an anthracene compound represented by formula (3-H), a compound having a reactive group at a desired position of the anthracene skeleton, 4 and a compound having a reactive group in a partial structure such as the structure of formula (A) as a starting material, and applying Suzuki coupling, Negishi coupling, or other known coupling reactions to manufacture. As the reactive group of the reactive compound, halogen or boric acid can be cited. As a specific manufacturing method, for example, reference can be made to the synthesis method of paragraphs

[0089] to

[0175] of International Publication No. 2014 / 141725.

[0730] [Fluorene compounds]

[0731] The compound represented by formula (4-H) basically functions as a main body.

[0732] [Chemistry 162]

[0733]

[0734] In formula (4-H),

[0735] R 1 To R 10 are independently hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the fluorene skeleton in formula (4-H) via a single bond or a linking group), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, at least one hydrogen in these groups may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group, and R 1 With R 2 , R 2 With R 3 , R 3 With R 4 , R 5 With R 6 , R 6 With R 7 , R 7 With R 8 or R 9 With R 10 They may be independently bonded to form a condensed ring or a spiro ring, at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group (the heteroaryl group may be bonded to the formed ring via a single bond or a linking group), a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group or an aryloxy group, at least one hydrogen in these may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group, and at least one hydrogen in the compound represented by formula (4-H) may be substituted by a halogen, a cyano group or a deuterium.

[0736] The details of each group in the definition of formula (4-H) can be referred to the description of the above-mentioned formula (1).

[0737] As R 1 To R 10 The alkenyl group in the alkylene group may be, for example, an alkenyl group having 2 to 30 carbon atoms, preferably an alkenyl group having 2 to 20 carbon atoms, more preferably an alkenyl group having 2 to 10 carbon atoms, further preferably an alkenyl group having 2 to 6 carbon atoms, and particularly preferably an alkenyl group having 2 to 4 carbon atoms. Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

[0738] In addition, specific examples of heteroaryl groups include monovalent groups represented by removing any one hydrogen atom from the compounds of the following formula (4-Ar1), formula (4-Ar2), formula (4-Ar3), formula (4-Ar4) or formula (4-Ar5).

[0739] [Chemistry 163]

[0740]

[0741] In Formula (4-Ar1) to Formula (4-Ar5), Y 1 are independently O, S or NR, R is phenyl, biphenyl, naphthyl, anthracenyl or hydrogen, and at least one hydrogen in the structures of Formula (4-Ar1) to (4-Ar5) may be substituted by phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, methyl, ethyl, propyl, or butyl.

[0742] These heteroaryl groups may be bonded to the fluorene skeleton in formula (4-H) via a single bond or a linking group. That is, the fluorene skeleton in formula (4-H) may be bonded to the heteroaryl group not only directly, but also via a linking group. Examples of the linking group include phenylene, biphenylene, naphthylene, anthracene, methylene, ethylene, -OCH 2 CH 2 -、-CH 2 CH 2 O-, or -OCH 2 CH 2 O-etc.

[0743] In addition, R in formula (4-H) 1 With R 2 , R 2 With R 3 , R 3 With R 4 , R 5 With R 6 , R 6 With R 7 or R 7 With R 8 can independently bond and form a condensed ring, R 9 With R 10 Can bond and form a spiro ring. 1 To R 8 The condensed ring formed is a ring condensed on the benzene ring in formula (4-H), and is an aliphatic ring or an aromatic ring. An aromatic ring is preferred, and examples of the structure containing the benzene ring in formula (4-H) include a naphthalene ring and a phenanthrene ring. 9 With R 10 The spiro ring formed is a ring spiro-bonded to the 5-membered ring in formula (4-H), and is an aliphatic ring or an aromatic ring. An aromatic ring is preferred, and examples thereof include a fluorene ring.

[0744] 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 R in formula (4-H) is 1 With R 2The compound formed by condensation of the benzene ring formed by bonding, R in formula (4-H) 3 With R 4 The compound formed by condensation of the benzene ring formed by bonding, in formula (4-H) R 1 To R 8 A compound in which neither of is bonded.

[0745] [Chemistry 164]

[0746]

[0747] R in formula (4-H-1), formula (4-H-2) and formula (4-H-3) 1 To R 10 The definition of is the same as that of R in formula (4-H) 1 To R 10 The same, R in formula (4-H-1) and formula (4-H-2) 11 To R 14 The definition of is also the same as R in formula (4) 1 To R 10 same.

[0748] The compound represented by formula (4-H) is preferably a compound represented by the following formula (4-H-1A), formula (4-H-2A) or formula (4-H-3A), and R in formula (4-H-1), formula (4-H-2) or formula (4-H-3) is 9 With R 10 A compound that is bonded to form a spiro-fluorene ring.

[0749] [Chemistry 165]

[0750]

[0751] R in formula (4-H-1A), formula (4-H-2A) and formula (4-H-3A) 2 To R 7 The definition is the same as that of R in formula (4-H-1), formula (4-H-2) and formula (4-H-3) 2 To R 7 The same, and R in formula (4-H-1A) and formula (4-H-2A) 11 To R 14 The definition of is also the same as R in formula (4-H-1) and formula (4-H-2) 11 To R 14 same.

[0752] In addition, all or part of hydrogen in the compound represented by formula (4-H) may be substituted by halogen, cyano or deuterium.

[0753] More specific examples of the main fluorene compound include compounds represented by the following structural formulas.

[0754] [Chemistry 166]

[0755]

[0756] [Dibenzo Compound]

[0757] As the main The compound is, for example, a compound represented by the following formula (5-H).

[0758] [Chemistry 167]

[0759]

[0760] In formula (5-H), R 1 To R 16 are independently hydrogen, aryl, heteroaryl (the heteroaryl may be connected to the dibenzoylmethane in formula (5-H) via a single bond or a linking group skeleton bond), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, at least one hydrogen in these groups may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group, and R 1 To R 16 The adjacent groups in the formula (5-H) may be bonded to each other to form a condensed ring, and at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group (the heteroaryl group may be bonded to the formed ring via a single bond or a linking group), a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group or an aryloxy group, and at least one hydrogen in these groups may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group, and at least one hydrogen in the compound represented by the formula (5-H) may be substituted by a halogen, a cyano group or a deuterium group.

[0761] The details of each group in the definition of formula (5-H) can be referred to the description of the above-mentioned formula (1).

[0762] Examples of the alkenyl group in the definition of formula (5-H) include alkenyl groups having 2 to 30 carbon atoms, preferably alkenyl groups having 2 to 20 carbon atoms, more preferably alkenyl groups having 2 to 10 carbon atoms, further preferably alkenyl groups having 2 to 6 carbon atoms, and particularly preferably alkenyl groups having 2 to 4 carbon atoms. Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

[0763] In addition, specific examples of heteroaryl groups 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).

[0764] [Chemistry 168]

[0765]

[0766] In formula (5-Ar1) to formula (5-Ar5), Y 1 are independently O, S or NR, R is phenyl, biphenyl, naphthyl, anthracenyl or hydrogen, and at least one hydrogen in the structures of Formula (5-Ar1) to (5-Ar5) may be substituted by phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, methyl, ethyl, propyl, or butyl.

[0767] These heteroaryl groups may be linked to the dibenzoylmethane in formula (5-H) via a single bond or a linking group. That is, the dibenzo The skeleton and the heteroaryl group may be bonded not only directly but also via a linking group. Examples of the linking group include phenylene, biphenylene, naphthylene, anthracene, methylene, ethylene, -OCH 2 CH 2 -、-CH 2 CH 2 O-, or -OCH 2 CH 2 O-etc.

[0768] The compound represented by formula (5-H) is preferably 1 , R 4 , R 5 , R 8 , R 9 , R 12 , R 13 and R 16 In the above case, R in formula (5-H) 2 , R 3 , R 6 , R 7 , R 10 , R 11 , R 14 and R 15 Preferably, each of them is independently hydrogen, phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, a monovalent group having a structure of formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5) (a monovalent group having the above structure may be substituted by a phenylene group, a biphenylene group, a naphthylene group, anthracenyl group, a methylene group, an ethylene group, -OCH2 CH 2 -、-CH 2 CH 2 O-, or -OCH 2 CH 2 O- and dibenzo backbone bond), methyl, ethyl, propyl, or butyl.

[0769] The compound represented by formula (5-H) is more preferably 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 In the above case, R in formula (5-H) 3 , R 6 , R 11 , R 14 At least one (preferably one or two, more preferably one) of the following is a phenylene, biphenylene, naphthylene, anthracene, methylene, ethylene, -OCH 2 CH 2 -、-CH 2 CH 2 O- or -OCH 2 CH 2 O- is a monovalent group of the structure of formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5), at least one of which (i.e., other than the position replaced by the monovalent group having the structure) is hydrogen, phenyl, biphenyl, naphthyl, anthracenyl, methyl, ethyl, propyl or butyl, and at least one of the hydrogens can be replaced by phenyl, biphenyl, naphthyl, anthracenyl, methyl, ethyl, propyl or butyl.

[0770] In addition, as R in the formula (5-H) 2 , R 3 , R 6 , R 7 , R 10 , R 11 , R 14 and R 15 In the case of selecting a monovalent group having a structure represented by formula (5-Ar1) to formula (5-Ar5), at least one hydrogen in the structure can react with R in formula (5-H) 1 To R 16to form a single bond.

[0771] As the main More specific examples of the compound include compounds represented by the following structural formulas.

[0772] [Chemistry 169]

[0773]

[0774] [Chemistry 170]

[0775]

[0776] [Compound represented by any one of formula (H1), formula (H2) and formula (H3)]

[0777] As the host material, for example, a compound represented by any of the following formula (H1), formula (H2), and formula (H3) can be used.

[0778] [Chemistry 171]

[0779]

[0780] In formula (H1), formula (H2) and formula (H3), L 1 is a single bond, or a divalent group containing at least an arylene group or a heteroarylene group. 1 is a single bond, or is an arylene group having 6 to 24 carbon atoms, a heteroarylene group having 2 to 24 carbon atoms, a heteroarylenearylene group having 6 to 24 carbon atoms, or an aryleneheteroarylenearylene group having 6 to 24 carbon atoms, or any two of these groups are replaced by -O-, -S-, -CH 2 -、-Si(-Arx) 2 -(Arx is an aryl group) or a cycloalkylene group to form a divalent group. 1 The arylene group in is preferably an arylene group having 6 to 16 carbon atoms, more preferably an arylene group having 6 to 12 carbon atoms, and particularly preferably an arylene group having 6 to 10 carbon atoms. Specifically, divalent groups such as a benzene ring, a biphenyl ring, a terphenyl ring, and a fluorene ring can be mentioned. 1The heteroarylene group in the formula (I) is preferably a heteroarylene group having 2 to 24 carbon atoms, more preferably a heteroarylene group having 2 to 20 carbon atoms, further preferably a heteroarylene group having 2 to 15 carbon atoms, and particularly preferably a heteroarylene group having 2 to 10 carbon atoms. Specifically, examples thereof include a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring (such as a furazan ring), a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, divalent groups such as 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, phenoxathiol ring, phenoxazine ring, phenothiazine ring, phenazine ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, and thianthrene ring. At least one hydrogen in the compounds represented by the above formulae may be substituted with at least one group selected from the substituent group Z or deuterium, for example, alkyl having 1 to 6 carbon atoms, cyano, halogen or deuterium.

[0781] As preferred specific examples, compounds represented by any of the following structural formulas can be cited. In addition, in the following structural formulas, at least one hydrogen can be substituted by halogen, cyano, alkyl having 1 to 4 carbon atoms (such as methyl or tert-butyl), phenyl or naphthyl.

[0782] [Chemistry 172]

[0783]

[0784] [Chemistry 173]

[0785]

[0786] [Chemistry 174]

[0787]

[0788] [Chemistry 175]

[0789]

[0790] [Hole-transporting host material (HH) and electron-transporting host material (EH)]

[0791] The hole transporting host material (HH) and the electron transporting host material (EH) satisfy the following relationship with respect to the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO).

[0792] The HOMO of the hole-transporting host material (HH) is shallower than the HOMO of the electron-transporting host material (EH), and the LUMO of the electron-transporting host material (EH) is deeper than the LUMO of the hole-transporting host material (HH).

[0793] In addition, it is preferred that the HOMO of the emissive dopant is shallower than the HOMO of the hole-transporting host material (HH), or the LUMO of the emissive dopant is deeper than the LUMO of the electron-transporting host material (EH).

[0794] In addition, from the viewpoint of promoting rather than inhibiting the generation of TADF in the light-emitting layer, the lowest excited triplet level (E T1 ) is higher than the highest E T1 E of the emission dopant or auxiliary dopant T1 Specifically, the E of the main material T1 Preferably, the E of the emitting dopant or the auxiliary dopant is T1 It is higher by 0.01 eV or more, more preferably higher by 0.03 eV or more, and even more preferably higher by 0.1 eV or more. T1 It is preferably 2.47 eV or more, more preferably 2.49 eV or more, and further preferably 2.56 eV or more.

[0795] In addition, it is also preferred to use a hole transporting host material in the hole transport layer adjacent to the light-emitting layer, and to use an electron transporting host material in the electron transport layer adjacent to the light-emitting layer. This is because it is not easy to cause carrier leakage and energy leakage from the light-emitting layer to the adjacent layer, and a high-efficiency organic EL element can be obtained. The host material (hole transporting host material) in the light-emitting layer may be the same as or different from the hole transport layer material. In addition, the host material (electron transporting host material) in the light-emitting layer may be the same as or different from the material of the electron transport layer.

[0796] Examples of preferred hole transport host materials (HH) include compounds represented by formula (HH-1), or compounds having a partial structure represented by formula (HH-1) and having a structure containing at least three rings selected from the group consisting of an aryl ring and a heteroaryl ring. The compounds preferably do not contain an imine structure (-N=C-; partial structure containing a heteroaryl ring), boron (>B-), and a cyano group (CN).

[0797] [Chemistry 176]

[0798]

[0799] In formula (HH-1),

[0800] Q is >O, >S or >NA H ,

[0801] One carbon atom adjacent to the carbon atom bonded to Q in each of the two phenyl groups in formula (HH-1) may be bonded to each other via L.

[0802] L is a single bond, >O, >S or >C(-A H ) 2 ,

[0803] A H is hydrogen, aryl or heteroaryl, and >C(-A H ) 2 Two A's H Can bond to each other.

[0804] When the hole transport host material includes the structure represented by formula (HH-1) as a partial structure, it may include one of the partial structures, but it is also preferred to include two or more. In the case of including two or more, the two or more partial structures may be the same as or different from each other. The two or more partial structures may be bonded to each other through a single bond, or they may be bonded in a manner that any ring contained in the partial structure is shared, or they may be bonded in a manner that any ring contained in the partial structure is condensed with each other. The partial structure may further have a substituent selected from an aryl group, a heteroaryl group, a diarylamino group, or an aryloxy group.

[0805] The compound represented by the formula (HH-1) or the compound having the partial structure represented by the formula (HH-1) has a structure containing at least three rings selected from the group consisting of aryl rings and heteroaryl rings. The number of rings contained is preferably 6 or more, more preferably 8 or more. In addition, it is preferably 20 or less, more preferably 15 or less, and further preferably 10 or less. The number of rings refers to the number of single rings, and with respect to condensed rings, it is the number obtained by counting the single rings constituting the condensed rings.

[0806] The hole transport host material is preferably a compound comprising one or more partial structures selected from the group consisting of a triarylamine structure, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, and a condensed polycyclic ring containing phenoxazine or phenothiazine. The hole transport host material may contain one such partial structure, but preferably contains two or more. In the case of containing two or more, the two or more partial structures may be the same or different from each other.

[0807] Specific examples of the hole-transporting host material include the following compounds.

[0808] [Chemistry 177]

[0809]

[0810] [Chemistry 178]

[0811]

[0812] [Chemistry 179]

[0813]

[0814] [Chemistry 180]

[0815]

[0816] [Chemistry 181]

[0817]

[0818] [Chemistry 182]

[0819]

[0820] [Chemistry 183]

[0821]

[0822] [Chemistry 184]

[0823]

[0824] [Chemistry 185]

[0825]

[0826] [Chemistry 186]

[0827]

[0828] [Chemistry 187]

[0829]

[0830] [Chemistry 188]

[0831]

[0832] [Chemistry 189]

[0833]

[0834] Among the above, preferred are HH-1-1, HH-1-2, HH-1-4 to HH-1-12, HH-1-17, HH-1-18, HH-1-20 to HH-1-24, and HH-1 -82, HH-1-84~HH-1-89, HH-1-91, HH-1-92, HH-1-106~HH-1-108, and HH-1-109~HH-1-115.

[0835] Examples of electron transport host materials (EH) include compounds represented by formula (EH-1A) to (EH-1D), or compounds having partial structures represented by formula (EH-1A) to (EH-1D) and having a structure comprising at least three rings selected from the group consisting of aryl rings and heteroaryl rings.

[0836] [Chemistry 190]

[0837]

[0838] In Formula (EH-1A) to Formula (EH-1D),

[0839] Ar is a heteroaryl ring containing N═C as a partial structure constituting the ring,

[0840] Z is a single bond, -O-, -S-, or -N(-A E )-,

[0841] The carbon atoms adjacent to the carbon atom bonded to Z and the A atom bonded to Z E Can bond to each other through L,

[0842] L is a single bond, >O, >S or >C(-A E ) 2 ,

[0843] A E is an aryl group, a heteroaryl group or a triarylsilyl group. In formula (EH-1C), any one of A E It can be a diarylamino group, with two A groups bonded to the same atom E They can bond with each other using L.

[0844] X is C, P or S,

[0845] When X is C, n=2, m=1,

[0846] When X is P, n=3, m=1,

[0847] When X is S, n=2, m=1-2.

[0848] The compounds represented by the formula (EH-1A) to the formula (EH-1D), or the compounds having the partial structures represented by the formula (EH-1A) to the formula (EH-1D), have a structure containing at least three rings selected from the group consisting of aryl rings and heteroaryl rings. The number of rings contained is preferably 4 or more, more preferably 6 or more, and further preferably 8 or more. In addition, it is preferably 20 or less, more preferably 15 or less, and further preferably 10 or less. The number of rings refers to the number as a single ring, and with respect to a condensed ring, it is set to the number obtained by counting the single rings constituting the condensed ring.

[0849] When the electron transport host material includes the structure represented by formula (EH-1A) to formula (EH-1D) as a partial structure, it may include one of the partial structures, but it is also preferred to include two or more. In the case of including two or more, the two or more partial structures may be the same as or different from each other. The two or more partial structures may be bonded to each other by a single bond, or they may be bonded in a manner that any ring contained in the partial structure is shared, or they may be bonded in a manner that any ring contained in the partial structure is condensed with each other. The partial structure may further have a substituent selected from an aryl group, a heteroaryl group, a diarylamino group, or an aryloxy group.

[0850] Specific examples of the electron transporting host material include the following compounds.

[0851] [Chemistry 191]

[0852]

[0853] [Chemistry 192]

[0854]

[0855] [Chemistry 193]

[0856]

[0857] [Chemistry 194]

[0858]

[0859] [Chemistry 195]

[0860]

[0861] [Chemistry 196]

[0862]

[0863] [Chemistry 197]

[0864]

[0865] [Chemistry 198]

[0866]

[0867] [Chemistry 199]

[0868]

[0869] Other preferred examples of electron transport host materials (compounds having a partial structure represented by formula (EH-1)) include polycyclic aromatic compounds represented by the following formula (EH-1b) or polymers of polycyclic aromatic compounds having multiple structures represented by the following formula (EH-1b).

[0870] [Chemistry 200]

[0871]

[0872] In formula (EH-1b),

[0873] R 1 , R 2 , R 3 , R 4 and R 5 (hereinafter also referred to as “R 1 ", etc.) are each independently hydrogen or a substituent. The substituent only needs to be a substituent selected from the substituent group Z.

[0874] In formula (EH-1b), X 1 and X 2 are independently >NR (amine nitrogen), >O, >C (-R) 2 , >S or >Se, X 1 and X 2 Different at the same time: >C(-R) 2 ,

[0875] The >NR and >C(-R) 2 R in each independently represents hydrogen or a substituent selected from the substituent group Z, which may be further substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group (the above being the second substituent), and the >NR and >C(-R) 2 The R in the above-mentioned may be independently bonded to at least one of the a ring, b ring and c ring via a linking group or a single bond.

[0876] Y 1 , Y 2 , Y 3 , Y 4 , Y 5 and Y 6 (hereinafter also referred to as "Y 1", etc.) are independently =C(-R)- or =N-(pyridinic nitrogen), at least one of which is =N-(pyridinic nitrogen),

[0877] The R in the ═C(—R)— is independently hydrogen or a substituent selected from the substituent group Z.

[0878] The R 1 , R 2 , R 3 , R 4 and R 5 , and as the Y 1 ~Y 6 Adjacent groups in R of =C(-R)- may bond to each other and form an aryl ring or a heteroaryl ring together with at least one of the a ring, b ring and c ring, and at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group, a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, a diarylboryl group (two aryl groups may be bonded via a single bond or a linking group), an alkyl group, a cycloalkyl group, an alkoxy group or an aryloxy group (the above are the first substituents), and at least one hydrogen in these groups may be further substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group (the above are the second substituents).

[0879] At least one hydrogen in the compound and structure represented by formula (EH-1b) may be substituted by cyano, halogen or deuterium.

[0880] In formula (EH-1b), R 1 , R 2 , R 3 , R 4 and R 5 are hydrogen, or R 3 and R 4 are hydrogen and are selected from R 1 , R 2 and R 5 Any one or more of the group is a substituent other than hydrogen, and the others are hydrogen. As a substituent, an alkyl group, an aryl group that may be substituted by an alkyl group or a heteroaryl group, a heteroaryl group that may be substituted by an alkyl group or an aryl group, or a diarylamino group that may be substituted by an alkyl group or an aryl group is preferred. At this time, as an alkyl group, an alkyl group having 1 to 6 carbon atoms (methyl, tert-butyl, etc.) is preferred, as an aryl group, a phenyl group or a biphenyl group is preferred, and as a heteroaryl group, a triazine group, a carbazolyl group (2-carbazolyl, 3-carbazolyl, 9-carbazolyl, etc.), a pyrimidinyl group, a pyridyl group, a dibenzofuranyl group or a dibenzothienyl group is preferred. As specific examples, phenyl, biphenyl, diphenyltriazine group, carbazolyltriazine group, monophenylpyrimidinyl group, diphenylpyrimidinyl group, carbazolyltriazine group, pyridyl group, dibenzofuranyl group and dibenzothienyl group can be cited.

[0881] Y 1etc. are independently =C(-R)- or =N-, and at least one is =N-. 1 ~Y 6 Any of may be =N-. Preferably Y 1 and Y 6 =N-(ring a is a pyrimidine ring), Y 1 or Y 6 =N-(ring a is a pyridine ring), Y 2 and Y 5 =N- (ring b and ring c are pyridine rings), Y 3 and Y 4 =N- (ring b and ring c are pyridine rings), Y 2 ~Y 5 =N- (ring b and ring c are pyrimidine rings), Y 1 , Y 3 , Y 4 and Y 6 =N- (ring a is a pyrimidine ring, ring b and ring c are pyridine rings), Y 1 , Y 2 , Y 5 and Y 6 =N- (ring a is a pyrimidine ring, ring b and ring c are pyridine rings), Y 1 ~Y 6 =N- (ring a, ring b and ring c are pyrimidine rings), Y 2 or Y 5 =N- (the b ring or the c ring is a pyridine ring).

[0882] In addition to the above arrangement relationship of =N-, it is preferred that X 1 and X 2 is >0, and is preferably a polycyclic aromatic compound including a partial structure represented by any of the following formulae.

[0883] [Chemistry 201]

[0884]

[0885] In particular, polycyclic aromatic compounds containing a partial structure represented by formula (EH-1b-N1) have a higher E S1 , high E T1 , small ΔE S1T1 .

[0886] Specific examples of the polycyclic aromatic compound represented by formula (EH-1b) are shown below.

[0887] [Chemistry 202]

[0888]

[0889] [Chemistry 203]

[0890]

[0891] [Chemistry 204]

[0892]

[0893] [Chemistry 205]

[0894]

[0895] [Chemistry 206]

[0896]

[0897] [Chemistry 207]

[0898]

[0899] Among the above, preferred are EH-1-1 to EH-1-4, EH-1-10, EH-1-21 to EH-1-25, EH-1-32, EH-1-33, EH-1-51 to EH-1-59, EH-1-61, EH-1-66, EH-1-68, EH-1-71, and EH-1-7. 2. EH-1-90, EH-1-94~EH-1-99, EH-1-100, EH-1-101, EH-1-104, EH-1- 115. EH-1-117, EH-1-120, EH-1-122, EH-1-123, EH-1-127~EH-1-130.

[0900] [Combination of hole-transporting host material and electron-transporting host material]

[0901] The combination of the hole transporting host material and the electron transporting host material is determined by the HOMO, LUMO and the lowest excited triplet energy level (E T1 ) to select.

[0902] Regarding HOMO and LUMO, a combination is selected in which the HOMO (HH) of the hole-transporting host material is shallower than the HOMO (EH) of the electron-transporting host material, and the LUMO (EH) of the electron-transporting host material is deeper than the LUMO (HH) of the hole-transporting host material. More specifically, a combination in which HOMO (HH) is at least 0.10 eV shallower than HOMO (EH), and LUMO (HH) is at least 0.10 eV deeper than HOMO (EH) is preferably selected, a combination in which HOMO (HH) is at least 0.20 eV shallower than HOMO (EH), and LUMO (HH) is at least 0.20 eV deeper than HOMO (EH) is more preferably selected, and a combination in which HOMO (HH) is at least 0.25 eV shallower than HOMO (EH), and LUMO (HH) is at least 0.25 eV deeper than HOMO (EH) is further preferably selected.

[0903] The hole transporting host material and the electron transporting host material may be a combination of an association body called an exciplex. It is generally known that an exciplex is easily formed between a material having a relatively deep LUMO level and a material having a shallow HOMO level. Regarding the interaction between the hole transporting host material and the electron transporting host material, specifically whether an exciplex is formed, it can be judged in the following manner: a monolayer film containing only the hole transporting host material and the electron transporting host material is formed in the same manner as the formation conditions of the light-emitting layer, and the luminescence spectrum (fluorescence, phosphorescence spectrum) is measured. For the obtained luminescence spectrum, it is compared with the luminescence spectrum displayed by each of the hole transporting host material and the electron transporting host material separately. It can be judged in the following manner: the spectrum of the mixed film containing the hole transporting host material and the electron transporting host material shows a different luminescence wavelength from the spectrum of the film of the hole transporting host material and the spectrum of the film of the electron transporting host material. Specifically, as long as the peak wavelength of the spectrum differs by more than 10nm, it can be used as an indicator.

[0904] As specific examples of the combination of a hole transporting host material and an electron transporting host material that do not form an exciplex, the following combinations can be cited. T1The physical property values ​​of, in the hole transport host material, preferably a compound having carbazole, dibenzofuran, dibenzothiophene, triarylamine, indolecarbazole and benzoxazinephenoxazine as a partial structure, more preferably a compound having carbazole, dibenzofuran and dibenzothiophene as a partial structure, and further preferably a compound having carbazole as a partial structure. Similarly, in the electron transport host material, preferably a compound having pyridine, triazine, phosphine oxide, benzofuranopyridine and dibenzooxasiloline as a partial structure, more preferably a compound having triazine, phosphine oxide, benzofuranopyridine and dibenzooxasiloline as a partial structure, and further preferably a compound having triazine.

[0905] More specifically, the hole transport host material is preferably selected from the group consisting of HH-1-1, HH-1-2, HH-1-4 to HH-1-12, HH-1-17, HH-1-18, HH-1-20 to HH-1-24, HH-1-82, HH-1-84 to HH-1-89, HH-1-91, HH-1-92 and HH-1-106 to HH-1-108, and the electron transport host material is preferably selected from the group consisting of EH-1-1 to EH-1-4, EH-1-10, EH-1-21~EH-1-25, EH-1-32, EH-1-33, EH-1-51~EH-1-59, EH-1-61, EH-1-71, EH-1-72, EH-1-90, In the group consisting of EH-1-100, EH-1-101, EH-1-104, EH-1-117, EH-1-120, EH-1-122, EH-1-123, and EH-1-127~EH-1-130. Preferred examples of combinations include compound HH-1-1 and compound EH-1-22, compound HH-1-1 and compound EH-1-23, compound HH-1-1 and compound EH-1-24, compound HH-1-2 and compound EH-1-22, compound HH-1-2 and compound EH-1-23, compound HH-1-2 and compound EH-1-24, or compound HH-1-1 and compound EH-1-128.

[0906] As specific examples of the combination of a hole transporting host material and an electron transporting host material that form an exciplex, the following combinations can be cited. T1The physical property values ​​of, in the hole transport host material, preferably a compound having carbazole, triarylamine, indolecarbazole and benzoxazine-phenoxazine as a partial structure, more preferably a compound having triarylamine, indolecarbazole and benzoxazine-phenoxazine as a partial structure, and further preferably a compound having triarylamine as a partial structure. Similarly, in the electron transport host material, preferably a compound having pyridine, triazine, phosphine oxide and benzofuranopyridine as a partial structure, more preferably a compound having triazine, phosphine oxide, benzofuranopyridine and dibenzooxasiloline as a partial structure, and further preferably a compound having phosphine oxide and triazine.

[0907] More specifically, the hole transport host material is preferably selected from the group consisting of HH-1-1, HH-1-2, HH-1-11, HH-1-12, HH-1-17, HH-1-18, HH-1-23, HH-1-24, and HH-1-115, and the electron transport host material is preferably selected from the group consisting of EH-1-1 to EH-1-4, EH-1-21 to EH-1-25, EH-1 -51~EH-1-57, EH-1-59, EH-1-66, EH-1-68, EH-1-90, EH-1-94, EH-1-99, EH-1-100, EH-1-101, EH-1-104, EH-1-117, EH-1-120, EH-1-122, EH-1-123, and the group consisting of EH-1-127~EH-1-130. Preferred examples of combinations include compound HH-1-1 and compound EH-1-21, compound HH-1-2 and compound EH-1-21, compound HH-1-12 and compound EH-1-94, compound HH-1-12 and compound EH-1-117, compound HH-1-1 and compound EH-1-130, compound HH-1-33 and compound EH-1-117, compound HH-1-48 and compound EH-1-117 or compound HH-1-49 and compound EH-1-117, and compound HH-1-115 and compound EH-1-99.

[0908] In addition, for specific combinations of hole-transporting host materials and electron-transporting host materials, see:

[0909] Organic Electronics (66 (2019) 227-24), Advanced Functional Materials (25 (2015) 361-366.), Advanced Materials (26 (2014) 4730-4734.), ACS Applied Materials and Interfaces (8 (2016) 32984-32991.), ACS Applied Materials and Interfaces (2016, 8, 9806-9810), ACS Applied Materials and Interfaces (2016, 8, 32984-32991), Journal of Materials Chemistry (C, 2018, 6, 8784-8792), Angewandte Chemie (2018, 6, 8784-8792), International Edition.) (2018, 57, 12380-12384), Advanced Functional Materials (24, 2014, 3970), Advanced Materials (26, 2014, 5684), Synthetic Metals (201, 2015, 49), Nature Photonics (16, 212-218 (2022)), etc.

[0910] <Assisted dopant (thermally activated delayed phosphor or phosphorescent material)>

[0911] The light-emitting layer also preferably contains an emitting dopant, a host material, and an auxiliary dopant. The auxiliary dopant is preferably a thermally activated delayed fluorescent substance or a phosphorescent material.

[0912] As described above, the polycyclic aromatic compound including the structural unit represented by the formula (1) has its interaction with adjacent molecules suppressed, and can be preferably used as an emitting dopant for a TAF device or a PSF device.

[0913] In the present embodiment, as the main compound, a known compound can be used, for example, a compound having at least one of a carbazole ring and a furan ring can be listed, wherein it is preferably a compound formed by bonding at least one of a furanyl group and a carbazole group to at least one of an arylene group and a heteroarylene group. As a specific example, compounds represented by any one of formula (H1), formula (H2) and formula (H3), in particular mCP or mCBP, compound HH-1-115 and compound EH-1-99, etc. can be listed. In addition, TADF-active compounds can also be used in the main compound. In the present embodiment, it is also preferred to use a combination of a hole transporting main material and an electron transporting main material as the main body.

[0914] From the viewpoint of promoting rather than hindering the generation of TADF in the light-emitting layer, the lowest excited triplet energy level E(1, T, Sh) of the main compound obtained from the shoulder peak on the short-wavelength side of the peak of the phosphorescence spectrum is preferably higher than the lowest excited triplet energy levels E(2, T, Sh) and E(3, T, Sh) of the emitting dopant or auxiliary dopant having the highest lowest excited triplet energy level in the light-emitting layer. Specifically, compared with E(2, T, Sh) and E(3, T, Sh), the lowest excited triplet energy level E(1, T, Sh) of the main compound is preferably 0.01 eV or more higher, more preferably 0.03 eV or more higher, and further preferably 0.1 eV or more higher.

[0915] [Thermally activated delayed phosphor]

[0916] The so-called "thermally activated delayed fluorescence" refers to a compound that absorbs thermal energy and undergoes reverse intersystem crossing from the lowest excited triplet state to the lowest excited singlet state, and is radiatively deactivated from the lowest excited singlet state, thereby emitting delayed fluorescence. The so-called "thermally activated delayed fluorescence" also includes the case where a higher-order triplet state is passed during the excitation process from the lowest excited triplet state to the lowest excited singlet state. For example, there are the papers published by Monkman et al. of Durham University (Nature Communications (7: 13680, digital object identifier (DOI) : 10.1038 / ncomms13680)), the papers published by Hosokai et al. of the National Institute of Advanced Industrial Science and Technology (Hosokai et al., Science Advances (Sci. Adv.) (2017; 3: e1603282)), and the papers published by Sato et al. of Kyoto University (Scientific Reports (2017)). 4820, DOI: 10.1038 / s41598-017-05007-7)), and a society paper by Sato et al. of Kyoto University (98th Spring Annual Meeting of the Chemical Society of Japan, publication number: 2I4-15, "Mechanism of high-efficiency luminescence in organic electroluminescence using diazaboranaphthoanthracene (DABNA) as a luminescent molecule," Journal of the Graduate School of Engineering, Kyoto University The present invention relates to a sample containing a target compound, and the target compound is determined to be a "thermally activated delayed fluorescent substance" by observing a slow fluorescent component when the fluorescence lifetime is measured at 300K. Here, the so-called slow fluorescent component refers to a component with a fluorescence lifetime of 0.1 μsec or more. The fluorescence lifetime can be measured, for example, using a fluorescence lifetime measuring apparatus (manufactured by Hamamatsu Photonics Co., Ltd., C11367-01).

[0917] In the light-emitting layer further including a "thermally active delayed phosphor" as an auxiliary dopant, the polycyclic aromatic compound of the present invention can function as an emitting dopant. That is, the "thermally active delayed phosphor" can function as an auxiliary dopant that assists the light emission of the polycyclic aromatic compound of the present invention.

[0918] In this specification, an organic electroluminescent element using a thermally activated delayed phosphor as an assisting dopant may be referred to as a "TAF element" (TADF Assisting Fluorescence element).

[0919] The so-called "host compound" in the TAF element refers to a compound whose lowest excited singlet energy level obtained from the shoulder peak on the short-wavelength side of the peak of the fluorescence spectrum is higher than the lowest excited singlet energy level of the thermally active delayed phosphor as an auxiliary dopant and the emitting dopant.

[0920] The thermally active delayed phosphor (TADF compound) used in the TAF element is preferably the following donor-acceptor type thermally active delayed phosphor (DA-type TADF compound): it is designed to use an electron-donating substituent called a donor and an electron-accepting substituent called an acceptor to localize the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in the molecule to produce efficient reverse intersystem crossing.

[0921] Here, in this specification, the so-called "electron donating substituent" (donor) refers to the substituent and partial structure locally present at HOMO in the thermally active delayed phosphor molecule, and the so-called "electron accepting substituent" (acceptor) refers to the substituent and partial structure locally present at LUMO in the thermally active delayed phosphor molecule.

[0922] Generally speaking, due to the structure of the thermally activated delayed fluorescent material using donors or acceptors, the spin orbit coupling (SOC) is large, and the exchange interaction between HOMO and LUMO is small, so ΔE S1T1Small, so a very fast reverse intersystem crossing speed can be obtained. By using the polycyclic aromatic compound of the present invention as an emitting dopant and using a thermally active delayed phosphor (TADF material) as an auxiliary dopant, an element that satisfies any one or all of high efficiency, high color purity and long life can be provided. The thermally active delayed phosphor can be any compound whose luminescence spectrum overlaps at least partially with the absorption spectrum of the polycyclic aromatic compound of the present invention. The polycyclic aromatic compound and the thermally active delayed phosphor of the present invention may be both contained in the same layer, or in adjacent layers or other adjacent layers.

[0923] As the thermally active 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 active delayed phosphor of the present invention, for example, the structure 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, benzothiophenocarbazole, phenyldihydroindolecarbazole, phenylbicarbazole, bicarbazole, tercarbazole, diphenylcarbazole-based amine, tetraphenylcarbazole-based diamine, phenoxazine, dihydrophenazine, phenothiazine, dimethyldihydroacridine, diphenylamine, bis(tert-butylphenyl)amine, N1-(4-(diphenylamino)phenyl)-N4,N4-diphenylbenzene-1,4-diamine, dimethyltetraphenyldihydroacridine diamine, tetramethyl-dihydro-indenoacridine and diphenyl-dihydrodibenzazasilin, etc. Examples of the acceptor structure include sulfonyldiphenyl, benzophenone, phenylenebis(phenyl ketone), benzonitrile, isonicotinonitrile, phthalonitrile, isophthalonitrile, terephthalonitrile, benzenetricarbonitrile, triazole, oxazole, thiadiazole, benzothiazole, benzobis(thiazole), benzoxazole, benzobis(oxazole), quinoline, benzimidazole, dibenzoquinoxaline, heptaazaphenalene, thioxanthone dioxide, dimethylanthrone, anthracene dione, 5H-cycloheptyl[1,2-b:5,4-b′]bipyridine, fluorene dicarbonitrile, triphenyltriazine, pyrazine dicarbonitrile, pyrimidine, phenylpyrimidine, methylpyrimidine, pyridine dicarbonitrile, dibenzoquinoxaline dicarbonitrile, bis(phenylsulfonyl)benzene, dimethylthioxanthene dioxide, thianthracene tetraoxide, and tri(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.

[0924] The compound used as an auxiliary dopant of the light-emitting layer in the TAF device is preferably a thermally activated delayed phosphor, and its emission spectrum at least partially overlaps with the absorption peak of the emitting dopant.

[0925] [Phosphorescent materials (auxiliary dopants)]

[0926] In the light-emitting layer, a phosphorescent material can be used as an auxiliary dopant. In this specification, an organic electroluminescent element using a phosphorescent material as an auxiliary dopant is sometimes referred to as a phosphorescent auxiliary element: a phosphor-sensitized fluorescent element, a PSF element. Phosphorescent materials utilize the intramolecular spin-orbit interaction (heavy atom effect) caused by metal atoms to obtain light emission from an excited triplet state. As such a phosphorescent material, for example, a luminescent metal complex can be used. As the luminescent metal complex, for example, compounds represented by the following formula (B-1) and the following formula (B-2) can be listed.

[0927] [Chemistry 208]

[0928]

[0929] In formula (B-1), M is at least one selected from the group consisting of Ir, Pt, Au, Eu, Ru, Re, Ag and Cu, n is an integer of 1 to 3, and "XY" are each independently a bidentate ligand.

[0930] In formula (B-2), M is at least one selected from the group consisting of Pt, Re and Cu, and "WXYZ" is a tetradentate ligand.

[0931] In formula (B-1), M is preferably Ir and n is preferably 3 from the viewpoint of efficiency and life.

[0932] In formula (B-2), M is preferably Pt from the viewpoint of efficiency and life.

[0933] The ligand (XY) in formula (B-1) has at least one ligand selected from the group consisting of: The ligand (WXYZ) in formula (B-2) has at least one ligand selected from the group consisting of: as a part thereof.

[0934] [Chemistry 209]

[0935]

[0936] In the formula,

[0937] It is bonded to the central metal M at ---,

[0938] Y is independently BRe NR e , PR e ,O,S,Se,C=O,S=O,SO 2 , CR e R f 、SiR e R f , or GeR e R f ,

[0939] The aromatic carbon CH in the ring can be substituted with N independently.

[0940] R e and R f Can be condensed or bonded to form a ring,

[0941] R a , R b , R c and R d Each independently is unsubstituted or substituted to a range from 1 to the maximum number of substitutions possible,

[0942] R a , R b , R c , R d , R e , and R f are independently hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silanyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, thiol or a combination thereof,

[0943] Among them, R a , R b , R c , and R d Any two adjacent substituents in the group may be condensed or bonded to form a ring, or may form a multidentate ligand.

[0944] Examples of the compound represented by formula (B-1) include Ir(ppy) 3 、Ir(ppy) 2 (acac), Ir(mppy) 3 、Ir(PPy) 2 (m-bppy), BtpIr(acac), Ir(btp) 2 (acac), Ir(2-phq) 3 、Hex-Ir(phq) 3 、Ir(fbi) 2(acac), fac-Tris(2-(3-p-xylyl)phenyl)pyridine iridium(III)(fac-Tris(2-(3-p-xylyl)phenyl)pyridine iridium(III)), Eu(dbm) 3 (Phen), Ir(piq) 3 、Ir(piq) 2 (acac), Ir(Fliq) 2 (acac), Ir(Flq) 2 (acac), Ru(dtb-bpy) 3 ·2(PF 6 )、Ir(2-phq) 3 、Ir(BT) 2 (acac), Ir(DMP) 3 、Ir(Mphq) 3 IR(phq) 2 tpy、fac-Ir(ppy) 2 Pc、Ir(dp)PQ 2 、Ir(Dpm)(Piq) 2 、Hex-Ir(piq) 2 (acac), Hex-Ir(piq) 3 、Ir(dmpq) 3 、Ir(dmpq) 2 (acac), FPQIrpic, etc.

[0945] Examples of the compound represented by formula (B-1) include the following compounds in addition to the above.

[0946] [Chemistry 210]

[0947]

[0948] [Chemistry 211]

[0949]

[0950] [Chemistry 212]

[0951]

[0952] In addition, iridium complexes described in Japanese Patent Laid-Open No. 2006-089398, Japanese Patent Laid-Open No. 2006-080419, Japanese Patent Laid-Open No. 2005-298483, Japanese Patent Laid-Open No. 2005-097263, and Japanese Patent Laid-Open No. 2004-111379, U.S. Patent Application Publication No. 2019 / 0051845, or Advanced Materials (26: 7116-7121), Nature Asia Materials (NPG Asia Materials) (13, 53 (2021)), Applied Physics Letters (Applied Physics Letters) (117, 253301 (2020)), Light-Emitting Diode-An Outlook On the Empirical Features and Its Recent Technological Progress Outlook (Light-Emitting Diode-An Outlook On the Empirical Features and Its Recent Technological Progress Outlook) can also be used. The platinum complex described in "Technological Advances" (Chapter 5).

[0953] <Other dopant materials>

[0954] The polycyclic aromatic compound containing the structural unit represented by formula (1) can be used in combination with other dopant materials. Among them, in one light-emitting layer, the other dopant materials are preferably less than 100% by mass, more preferably 50% by mass or less, further preferably 30% by mass or less, and particularly preferably 10% by mass or less, relative to the total mass of the polycyclic aromatic compound containing the structural unit represented by formula (1). As other dopant materials, known compounds can be used, and they can be selected from various materials according to the desired luminescent color. Specifically, for example, phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopyrene, dibenzopyrene, rubrene and Condensed ring derivatives such as benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, benzotriazole derivatives, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, imidazole derivatives, thiadiazole derivatives, triazole derivatives, pyrazoline derivatives, stilbene derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives or stilbenebenzene derivatives such as bisstyrylanthracene derivatives (Japanese Patent Laid-Open No. 1-245087), bisstyrylarylene derivatives (Japanese Patent Laid-Open No. 2-247278), diazabenzodiindene derivatives, furan derivatives, benzofuran derivatives, phenylisobenzofuran, dimesitylisobenzofuran, di(2-methylphenyl)isobenzofuran, di(2-trifluoromethylphenyl)isobenzofuran, isobenzofuran derivatives such as phenylisobenzofuran, dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7- Coumarin derivatives such as piperidinyl coumarin derivatives, 7-hydroxycoumarin derivatives, 7-methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolyl coumarin derivatives, 3-benzimidazolyl coumarin derivatives, 3-benzoxazolyl coumarin derivatives, dicyanomethylene pyran derivatives, dicyanomethylene thiopyran derivatives, polymethine derivatives, cyanine derivatives, oxybenzanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein Derivatives, pyrylium derivatives, quinolone derivatives, acridine derivatives, oxazine derivatives, phenyl ether derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, furanopyridine derivatives, 1,2,5-thiadiazolopyrene derivatives, pyrromethene derivatives, purple ring ketone derivatives, pyrrolopyrrole derivatives, squarylium salt derivatives, purple anthrone derivatives, phenazine derivatives, acridone derivatives, deazotflavin derivatives, fluorene derivatives and benzofluorene derivatives, etc.

[0955] As other dopant materials, it is also preferable to use a polycyclic aromatic compound containing boron described in International Publication No. 2015 / 102118, International Publication No. 2020 / 162600, paragraphs 0097 to 0269 of Japanese Patent Application Laid-Open No. 2021-077890, and the like.

[0956] 2-1-6. Electron injection layer and electron transport layer in organic electroluminescent element

[0957] The electron injection layer 107 plays a role of efficiently injecting electrons migrated from the cathode 108 into the light-emitting layer 105 or the electron transport layer 106. The electron transport layer 106 plays a role of efficiently transporting electrons injected from the cathode 108 or electrons injected from the cathode 108 via the electron injection layer 107 to the light-emitting layer 105. The electron transport layer 106 and the electron injection layer 107 are respectively formed by stacking or mixing one or more electron transport / injection materials, or are formed by a mixture of an electron transport / injection material and a polymer binder.

[0958] The so-called electron injection / transport layer is a layer responsible for injecting electrons from the cathode and then transmitting electrons, and it is desirable that the electron injection efficiency is high and the injected electrons are transmitted efficiently. Therefore, it is preferably a material with large electron affinity, large electron mobility, excellent stability, and impurities that are not easy to produce when manufacturing and using it. However, considering the transmission balance of holes and electrons, in the case of mainly playing the role of efficiently preventing the holes from the anode from being recombined and flowing to the cathode side, even if the electron transmission ability is not so high, it has the effect of improving luminous efficiency equally with the material with high electron transmission ability. Therefore, the electron injection / transport layer in the present embodiment may also include the function of the layer that can efficiently prevent the migration of holes.

[0959] The material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107 can be arbitrarily selected from compounds conventionally used as electron transfer compounds in photoconductive materials and known compounds used in electron injection layers and electron transport layers of organic EL elements.

[0960] As the material used in the electron transport layer or the electron injection layer, it is preferably containing at least one selected from the following compounds: a compound containing an aromatic ring or heteroaromatic ring containing one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon and phosphorus; a pyrrole derivative and its condensed ring derivative; and a metal complex with electron-accepting nitrogen. Specifically, it can be listed: condensed ring aromatic ring derivatives such as naphthalene and anthracene, styrene aromatic ring derivatives represented by 4,4'-bis(diphenylvinyl)biphenyl, purple ring ketone derivatives, coumarin derivatives, naphthalene dicarboximide derivatives, quinone derivatives such as anthraquinone or diphenoquinone, phosphine oxide derivatives, aryl nitrile derivatives and indole derivatives. As a metal complex with electron-accepting nitrogen, for example, hydroxyl azole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes and benzoquinoline metal complexes can be listed. These materials can be used alone or mixed with different materials.

[0961] In addition, specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, anthracene derivatives, phenanthroline derivatives, perirone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives (1,3-bis[(4-tert-butylphenyl)1,3,4-oxadiazolyl]phenylene, etc.), thiophene derivatives, triazole derivatives (N-naphthyl-2,5-diphenyl-1,3,4-triazole, etc.), thiadiazole derivatives, metal complexes of 8-hydroxyquinoline derivatives, hydroxyquinoline metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzoazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, Biologicals, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives (2,2'-bis(benzo[h]quinolin-2-yl)-9,9'-spirobifluorene, etc.), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (tris(N-phenylbenzimidazol-2-yl)benzene, etc.), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives, terpyridine derivatives (1,3-bis(2,2':6',2"-terpyridine-4'-yl)benzene, etc.), naphthyridine derivatives (bis(1-naphthyl)-4-(1,8-naphthyridin-2-yl)phenylphosphine oxide, etc.), aldazine derivatives, carbazole derivatives, indole derivatives, phosphine oxide derivatives, bisphenylvinyl derivatives, etc.

[0962] In addition, metal complexes having electron-accepting nitrogen can also be used, examples of which include hydroxyquinoline metal complexes, hydroxyoxazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes.

[0963] The materials can be used alone or in combination with different materials.

[0964] Among the above materials, preferred are borane derivatives, pyridine derivatives, fluoranthene derivatives, BO derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, aromatic nitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives, and hydroxyquinoline metal complexes.

[0965] The electron transport layer or the electron injection layer may further contain a substance that can reduce the material forming the electron transport layer or the electron injection layer. The reducing substance may be a variety of substances as long as it has a certain reducing property, for example, at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, alkali metal oxides, alkali metal halides, alkaline earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes, and rare earth metal organic complexes can be preferably used.

[0966] As preferred reducing substances, alkali metals such as Na (work function 2.36eV), K (work function 2.28eV), Rb (work function 2.16eV) or Cs (work function 1.95eV) or alkaline earth metals such as Ca (work function 2.9eV), Sr (work function 2.0eV~2.5eV) or Ba (work function 2.52eV) can be listed, and substances with a work function of 2.9eV or less are particularly preferred. Among these, the more preferred reducing substances are alkali metals of K, Rb or Cs, and more preferably Rb or Cs, and most preferably Cs. The reducing ability of these alkali metals is particularly high. By adding a relatively small amount of the alkali metal to the material forming the electron transport layer or the electron injection layer, the luminous brightness in the organic EL element can be improved or the life can be prolonged. In addition, as the reducing substance having a work function of 2.9 eV or less, a combination of two or more of these alkali metals is also preferred, and a combination containing Cs is particularly preferred, such as a combination of Cs and Na, Cs and K, Cs and Rb, or Cs and Na and K. By including Cs, the reducing ability can be efficiently exerted, and by adding it to the material forming the electron transport layer or the electron injection layer, the luminance of the light emission in the organic EL element can be improved or the life can be prolonged.

[0967] 2-1-7. Cathode in organic electroluminescent element

[0968] The cathode 108 plays a role of injecting electrons into the light-emitting layer 105 via the electron injection layer 107 and the electron transport layer 106 .

[0969] As the material forming the cathode 108, if it is a substance that can efficiently inject electrons into the organic layer, it is not particularly limited, and the same material as the material forming the anode 102 can be used. Among them, preferably metals such as tin, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium and magnesium or their alloys (magnesium-silver alloy, magnesium-indium alloy, aluminum-lithium alloy such as lithium fluoride / aluminum, etc.) and the like. In order to improve the efficiency of electron injection to improve the characteristics of the element, lithium, sodium, potassium, cesium, calcium, magnesium or alloys containing these low work function metals are effective. However, generally speaking, these low work function metals are unstable in the atmosphere in most cases. In order to improve this point, it is known that there is a method of doping a trace amount of lithium, cesium or magnesium into the organic layer and using an electrode with high stability. As other dopants, inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide and cesium oxide can also be used. Among them, it is not limited to these.

[0970] Furthermore, the following are preferred examples: in order to protect the electrode, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, or alloys of these metals, inorganic substances such as silicon dioxide, titanium dioxide and silicon nitride, polyvinyl alcohol, vinyl chloride, hydrocarbon polymer compounds, etc. are stacked. The method for making these electrodes is not particularly limited as long as it is a method that can achieve conduction such as resistance heating, electron beam evaporation, sputtering, ion plating and coating.

[0971] 2-1-8. Method for producing organic electroluminescent element

[0972] Each layer constituting the organic EL element can be formed by making the material to constitute each layer into a thin film using a method such as vapor deposition, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular stacking, printing, spin coating, casting, coating, etc. The film thickness of each layer formed in the above manner is not particularly limited and can be appropriately set according to the properties of the material, but is generally in the range of 2nm to 5000nm. The film thickness can generally be measured using a quartz oscillation film thickness measuring device or the like. When using the vapor deposition method for thin film formation, the vapor deposition conditions vary depending on the type of material, the target crystal structure and association structure of the film, etc. The vapor deposition conditions are generally preferably a boat heating temperature of +50°C to +400°C and a vacuum degree of 10 -6 Pa~10 -3 Pa, the vapor deposition rate is 0.01 nm / sec to 50 nm / sec, the substrate temperature is -150°C to +300°C, and the film thickness is appropriately set within the range of 2 nm to 5 μm.

[0973] When a direct current voltage is applied to the organic EL element obtained in the above manner, it can be applied with the anode as + polarity and the cathode as - polarity. If a voltage of about 2V to 40V is applied, light emission can be observed from the transparent or translucent electrode side (anode or cathode, or both). In addition, the organic EL element also emits light when a pulse current or an alternating current is applied. In addition, the waveform of the applied alternating current can be arbitrary.

[0974] Next, as an example of a method for producing an organic EL element, a method for producing an organic EL element including anode / hole injection layer / hole transport layer / light-emitting layer including a host material and a dopant material / electron transport layer / electron injection layer / cathode is described.

[0975] <Evaporation method>

[0976] On a suitable substrate, a thin film of an anode material is formed by a vapor deposition method to make an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. The main material and the dopant material are co-evaporated on the thin film to form a thin film as a light-emitting layer, and an electron transport layer and an electron injection layer are formed on the light-emitting layer, and then a thin film containing a cathode material is formed by a vapor deposition method as a cathode, thereby obtaining a target organic EL element. In addition, in the production of the organic EL element, the production order can also be reversed, and the cathode, electron injection layer, electron transport layer, light-emitting layer, hole transport layer, hole injection layer, anode are produced in the order of cathode, electron injection layer, electron transport layer, light-emitting layer, hole transport layer, hole injection layer, anode.

[0977] <Wet film forming method>

[0978] A low molecular weight compound capable of forming each organic layer of an organic EL element is prepared as a liquid organic layer-forming composition, and the composition is used to perform a wet film-forming method. In the absence of an appropriate organic solvent for dissolving the low molecular weight compound, the organic layer-forming composition may be prepared from a high molecular weight compound or the like, wherein the high molecular weight compound is polymerized together with other monomers or main chain polymers having a solubility function as a reactive compound substituted with a reactive substituent in the low molecular weight compound.

[0979] The wet film forming method generally forms a coating film by passing through the following process, wherein the process is a coating process of applying an organic layer forming composition on a substrate and a drying process of removing a solvent from the coated organic layer forming composition. In the case where the polymer compound has a cross-linking substituent (also referred to as a cross-linking polymer compound), the drying process is further cross-linked to form a polymer cross-linked body. Depending on the coating process, the method using a spin coater is called a spin coating method, the method using a slit coater is called a slit coating method, the method using a plate is called a gravure, lithography, reverse lithography, flexographic printing method, the method using an inkjet printer is called an inkjet method, and the method of blowing with a mist is called a spray method. There are methods such as air drying, heating, and reduced pressure drying in the drying process. The drying process can be performed only once, or it can be performed multiple times using different methods or conditions. In addition, for example, different methods can also be used, such as calcination under reduced pressure.

[0980] The wet film forming method refers to a film forming method using a solution, such as a partial printing method (inkjet method), a spin coating method or a casting method, a coating method, etc. The wet film forming method is different from the vacuum evaporation method in that it does not require the use of an expensive vacuum evaporation device and can be formed under atmospheric pressure. In addition, the wet film forming method can be large-scale or continuously produced, thereby reducing manufacturing costs.

[0981] On the other hand, compared with the vacuum evaporation method, the wet film forming method is sometimes difficult to laminate. When using the wet film forming method to make a laminated film, it is necessary to prevent the dissolution of the lower layer caused by the composition of the upper layer, and use a composition with controlled solubility, crosslinking of the lower layer, and an orthogonal solvent (orthogonal solvent, mutually insoluble solvent) etc. However, there are cases where it is difficult to use the wet film forming method for coating all films even if these technologies are used.

[0982] Therefore, a method is generally adopted in which only some layers are formed by a wet film-forming method and the remaining layers are formed by a vacuum deposition method to produce an organic EL element.

[0983] For example, the following shows a part of the procedure for manufacturing an organic EL element by applying the wet film formation method.

[0984] (Procedure 1) Anode film formation by vacuum deposition method

[0985] (Procedure 2) Film formation of a hole injection layer-forming composition containing a hole injection layer material by a wet film formation method

[0986] (Procedure 3) Film formation of a hole transport layer-forming composition containing a hole transport layer material by a wet film formation method

[0987] (Procedure 4) Film formation of a composition for forming a light-emitting layer containing a host material and a dopant material by a wet film formation method

[0988] (Procedure 5) Film formation of electron transport layer by vacuum deposition method

[0989] (Procedure 6) Film formation of electron injection layer by vacuum deposition method

[0990] (Procedure 7) Cathode film formation by vacuum deposition method

[0991] By going through the above process, an organic EL element including anode / hole injection layer / hole transport layer / light-emitting layer including a host material and a dopant material / electron transport layer / electron injection layer / cathode can be obtained.

[0992] Of course, for the electron transport layer and the electron injection layer, a layer-forming composition containing an electron transport layer material and an electron injection layer material can also be used to form a film by a wet film-forming method. In this case, it is preferred to use a method that prevents the lower light-emitting layer from dissolving, or a method of forming a film from the cathode side in the opposite manner to the above procedure.

[0993] <Other film forming methods>

[0994] Laser heating drawing method (Laser Induced Thermal Imaging (LITI)) can be used for film formation of the organic layer-forming composition. LITI refers to a method of heating and evaporating a compound attached to a substrate using a laser, and the organic layer-forming composition can be used in the material coated on the substrate.

[0995] <Optional process>

[0996] Before and after each film forming step, appropriate treatment steps, cleaning steps and drying steps may be appropriately added. Examples of treatment steps include exposure treatment, plasma surface treatment, ultrasonic treatment, ozone treatment, cleaning treatment using an appropriate solvent and heating treatment. Furthermore, a series of steps for making a bank may be mentioned.

[0997] Photolithography can be used in the production of the bank. As the bank material that can be photolithographically processed, positive resist materials and negative resist materials can be used. In addition, printing methods that can be patterned, such as inkjet printing, gravure lithography, reverse lithography, and screen printing, can also be used. At this time, a permanent resist material can also be used.

[0998] <Organic layer forming composition used in wet film forming method>

[0999] The composition for forming an organic layer is obtained by dissolving a low molecular compound that can form each organic layer of an organic EL element, or a high molecular compound obtained by polymerizing the low molecular compound, in an organic solvent. For example, the composition for forming a luminescent layer contains at least one dopant material, i.e., a polycyclic aromatic compound (or its high molecular compound) as a first component, at least one main material as a second component, and at least one organic solvent as a third component. The first component functions as a dopant component of the luminescent layer obtained from the composition, and the second component functions as a main component of the luminescent layer. The third component functions as a solvent that dissolves the first component and the second component in the composition, and provides a smooth and uniform surface shape by using the controlled evaporation rate of the third component itself during coating.

[1000] <Organic solvent>

[1001] The organic layer forming composition comprises at least one organic solvent. By controlling the evaporation rate of the organic solvent during film formation, the film forming property and the presence or absence of defects, surface roughness, and smoothness of the coating film can be controlled and improved. In addition, when using the inkjet method for film formation, the stability of the meniscus at the pinhole of the inkjet head can be controlled, and the ejection property can be controlled / improved. In addition, by controlling the drying rate of the film and the orientation of the derivative molecules, the electrical properties, luminescent properties, efficiency, and life of the organic EL element having the organic layer obtained by the organic layer forming composition can be improved.

[1002] The organic solvent is removed from the coating by drying processes such as vacuum, decompression, heating, etc. after film formation. When heating, from the perspective of improving the coating film-forming property, it is preferably carried out below the glass transition temperature (Tg) of at least one of the solutes + 30 ° C. In addition, from the perspective of reducing the residual solvent, it is preferably heated above the glass transition temperature (Tg) of at least one of the solutes -30 ° C. Even if the heating temperature is lower than the boiling point of the organic solvent, the organic solvent is also fully removed because the film is thin. In addition, it can be dried multiple times at different temperatures, and a variety of drying methods can also be used in combination.

[1003] (2) Specific examples of organic solvents

[1004] As the organic solvent used in the composition for forming the organic layer, alkylbenzene solvents, phenyl ether solvents, alkyl ether solvents, cyclic ketone solvents, aliphatic ketone solvents, monocyclic ketone solvents, solvents having a diester skeleton, and fluorine-containing solvents can be cited, but are not limited thereto. In addition, the solvents can be used alone or in combination.

[1005] <Optional ingredients>

[1006] The composition for forming an organic layer may contain an optional component within a range that does not impair its properties. Examples of the optional component include a binder and a surfactant.

[1007] <Composition and physical properties of the organic layer-forming composition>

[1008] The content of each component in the organic layer forming composition is determined from the viewpoints of good solubility, storage stability and film-forming properties of each component in the organic layer forming composition, high-quality film quality of the coating obtained from the organic layer forming composition, good ejection properties when using an inkjet method, and good electrical properties, luminescent properties, efficiency and life of an organic EL element having an organic layer made using the composition.

[1009] The composition for forming an organic layer can be prepared by appropriately selecting the components and stirring, mixing, heating, cooling, dissolving, dispersing, etc. by known methods. In addition, filtering, degassing (also called degassing), ion exchange treatment, and inert gas replacement / sealing treatment can also be appropriately selected after preparation.

[1010] 2-1-9. Application examples of organic electroluminescent elements

[1011] The present invention can also be applied to a display device including an organic EL element, a lighting device including an organic EL element, or the like.

[1012] A display device or lighting device including an organic EL element can be manufactured by a known method such as connecting the organic EL element of this embodiment to a known driving device, and can be driven using a known driving method such as DC driving, pulse driving, AC driving, etc. as appropriate.

[1013] As display devices, for example, panel displays such as color flat panel displays, flexible displays such as flexible color organic electroluminescent (EL) displays, etc. (for example, refer to Japanese Patent Laid-Open No. 10-335066, Japanese Patent Laid-Open No. 2003-321546, Japanese Patent Laid-Open No. 2004-281086, etc.). In addition, as display modes of displays, for example, matrix modes and segment modes can be listed. In addition, matrix display and segment display can coexist in the same panel.

[1014] In a matrix, pixels for display are arranged two-dimensionally in a grid or mosaic shape, etc., so that text or images are displayed by a collection of pixels. The shape or size of a pixel is determined according to the purpose. For example, in the image and text display of personal computers, monitors, and televisions, quadrilateral pixels with a side of less than 300 μm are usually used. In addition, in the case of large displays such as display screens, pixels with a side of mm are used. In the case of monochrome display, it is sufficient to arrange pixels of the same color. In the case of color display, red, green, and blue pixels are displayed in parallel. In the case, typical ones are triangular and stripe types. Moreover, as a driving method of the matrix, it can be either a line-sequential driving method or an active matrix. Line-sequential driving has the advantage of simple structure, but in the case of considering the operating characteristics, active matrix is ​​sometimes more excellent, so the driving method also needs to be used according to the purpose.

[1015] In the segmented method (type), a pattern is formed in a manner to display predetermined information, and the determined area is illuminated. Examples include: time or temperature display in a digital clock or thermometer, operating status display of audio equipment or induction cookers, and panel display of a car.

[1016] As lighting devices, for example, lighting devices such as indoor lighting, backlight sources of liquid crystal display devices, etc. can be listed (for example, refer to Japanese Patent Publication No. 2003-257621, Japanese Patent Publication No. 2003-277741, Japanese Patent Publication No. 2004-119211, etc.). Backlight sources are mainly used to improve the visibility of display devices that do not emit light by themselves, and are used for liquid crystal display devices, clocks, audio devices, automobile panels, display boards, and logos. In particular, as a backlight source for personal computers where thinning is becoming a problem in liquid crystal display devices, if it is considered that the existing methods are difficult to be thinned due to the inclusion of fluorescent lamps or light guide plates, the backlight source using the light-emitting element of this embodiment has the characteristics of being thin and lightweight.

[1017] 2-2. Other organic devices

[1018] The polycyclic aromatic compound of the present invention can be used not only in the organic electroluminescent element, but also in the preparation of organic field effect transistors or organic thin film solar cells.

[1019] An organic field effect transistor is a transistor that uses an electric field generated by voltage input to control current. In addition to a source electrode and a drain electrode, a gate electrode is also provided. An organic field effect transistor is a transistor in which an electric field is generated when a voltage is applied to the gate electrode, and the flow of electrons (or holes) flowing between the source electrode and the drain electrode can be arbitrarily blocked to control the current. Compared with a single transistor (bipolar transistor), a field effect transistor is easy to miniaturize and is often used as a component constituting an integrated circuit, etc.

[1020] Regarding the structure of an organic field effect transistor, generally, a source electrode and a drain electrode are provided in contact with an organic semiconductor active layer formed using the polycyclic aromatic compound of the present invention, and a gate electrode is provided via an insulating layer (dielectric layer) in contact with the organic semiconductor active layer. As an example of its element structure, the following structure can be cited.

[1021] (1) Substrate / gate electrode / insulator layer / source electrode, drain electrode / organic semiconductor active layer

[1022] (2) Substrate / gate electrode / insulator layer / organic semiconductor active layer / source electrode, drain electrode

[1023] (3) Substrate / organic semiconductor active layer / source electrode, drain electrode / insulator layer / gate electrode

[1024] (4) Substrate / source electrode, drain electrode / organic semiconductor active layer / insulator layer / gate electrode

[1025] The organic field effect transistor configured in this way can be used as a pixel driving switch element of an active matrix driving liquid crystal display or an organic electroluminescent display, etc.

[1026] Organic thin film solar cells have a structure in which an anode, a hole transport layer, a photoelectric conversion layer, an electron transport layer, and a cathode of ITO or the like are stacked on a transparent substrate such as glass. The photoelectric conversion layer has a p-type semiconductor layer on the anode side and an n-type semiconductor layer on the cathode side. The polycyclic aromatic compounds of the present invention can be used as materials for hole transport layers, p-type semiconductor layers, n-type semiconductor layers, and electron transport layers according to their physical properties. In organic thin film solar cells, the polycyclic aromatic compounds of the present invention can function as hole transport materials or electron transport materials. In addition to the above layers, organic thin film solar cells may also appropriately include a hole blocking layer, an electron blocking layer, an electron injection layer, a hole injection layer, a smoothing layer, and the like. In organic thin film solar cells, known materials used for organic thin film solar cells can be appropriately selected for use in combination.

[1027] 3. Wavelength conversion materials

[1028] The polycyclic aromatic compound of the present invention can be used as a wavelength conversion material. Currently, the application of multicolorization technology based on color conversion to liquid crystal displays or organic EL displays, lighting, etc. is being actively studied. The so-called color conversion is to convert the light emitted from the light source into light with a longer wavelength, for example, ultraviolet light or blue light is converted into green light or red light. The wavelength conversion material having the color conversion function is filmed, for example, combined with a blue light source, thereby being able to extract the three primary colors of blue, green, and red from the blue light source, that is, to extract white light. This white light source formed by combining the blue light source with the wavelength conversion film having the color conversion function is used as a light source unit, and combined with a liquid crystal drive part and a color filter, thereby being able to produce a full-color display. In addition, if there is no liquid crystal drive part, it can be directly used as a white light source, for example, it can be used as a white light source for light-emitting diode (LED) lighting, etc. In addition, a blue organic EL element is used as a light source, and is used in combination with a wavelength conversion film that converts blue light into green light and red light, thereby being able 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 into green light and red light, a low-cost full-color micro LED display can be produced.

[1029] The polycyclic aromatic compound of the present invention can be used as the wavelength conversion material. The wavelength conversion material containing the polycyclic aromatic compound of the present invention can be used to convert ultraviolet light or light from a light source or light-emitting element that generates blue light with a shorter wavelength into blue light or green light with high color purity suitable for use in a display device (a display device or a liquid crystal display device using an organic EL element). The adjustment of the converted color can be carried out by appropriately selecting the substituent of the polycyclic aromatic compound of the present invention, the binder resin used in the wavelength conversion composition described later, etc. The wavelength conversion material is prepared as a wavelength conversion composition containing the polycyclic aromatic compound of the present invention. In addition, the wavelength conversion composition can also be used to form a wavelength conversion film.

[1030] The wavelength conversion composition may contain a binder resin, other additives, and a solvent in addition to the polycyclic aromatic compound of the present invention. As the binder resin, for example, the resins described in paragraphs 0173 to 0176 of International Publication No. 2016 / 190283 may be used. As other additives, the compounds described in paragraphs 0177 to 0181 of International Publication No. 2016 / 190283 may be used. As the solvent, the description of the solvent contained in the light-emitting layer forming composition may be referred to.

[1031] The wavelength conversion film includes a wavelength conversion layer formed by curing the wavelength conversion composition. As a method for making a wavelength conversion layer from a wavelength conversion composition, reference can be made to a known film formation method. The wavelength conversion film may include only a wavelength conversion layer formed by a composition comprising a 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). Furthermore, the wavelength conversion film may also include a substrate layer, or a barrier layer for preventing the color conversion layer from deteriorating due to oxygen, moisture, or heat.

[1032] [Example]

[1033] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[1034] In the examples, APCI-MS (atmospheric pressure chemical ionization-mass spectrometry) refers to atmospheric pressure chemical ionization mass spectrometry.

[1035] <<Synthesis example>>

[1036] <Synthesis Example (1): Synthesis of Compound (1-1)>

[1037] Under nitrogen atmosphere, 1.60M tert-butyl lithium pentane solution (15.6 ml) was added to a flask containing the intermediate (Int-1-1) (12.3 g) and tert-butylbenzene (70 ml) at 0°C. After the addition was completed, the temperature was raised to 70°C and stirred for 0.5 hours, and the components with a boiling point lower than that of tert-butylbenzene were removed by reduced pressure distillation. The mixture was cooled to -50°C and added with boron tribromide (6.3 g), and the temperature was raised to room temperature and stirred for 0.5 hours. After that, the mixture was cooled to 0°C again and N,N-diisopropylethylamine (4.3 mL) was added, and the mixture was stirred at room temperature until the heat stopped, and then the temperature was raised to 100°C and heated and stirred for 1 hour. The reaction solution was cooled to room temperature, and an aqueous sodium acetate solution cooled by an ice bath was added, followed by ethyl acetate for separation. The organic layer was concentrated and purified using a silica gel short-path column (eluent: toluene / heptane = 1 / 1 (volume ratio)). The obtained crude product was recrystallized from toluene, thereby obtaining Compound (1-1) (1.8 g, yield 15%).

[1038] [Chemistry 213]

[1039]

[1040] The target product was confirmed by APCI-MS with m / z (M+H) = 1207.49.

[1041] <Synthesis Example (2): Synthesis of Compound (1-2)>

[1042] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-2) (1.5 g, yield 11%).

[1043] [Chemistry 214]

[1044]

[1045] The target product was confirmed by APCI-MS with m / z (M+H) = 1359.55.

[1046] <Synthesis Example (3): Synthesis of Compound (1-3)>

[1047] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-3) (1.3 g, yield 9%).

[1048] [Chemistry 215]

[1049]

[1050] The target product was confirmed by APCI-MS with m / z (M+H) = 1419.54.

[1051] <Synthesis Example (4): Synthesis of Compound (1-20)>

[1052] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-20) (1.6 g, yield 13%).

[1053] [Chemistry 216]

[1054]

[1055] The target product was confirmed by APCI-MS with m / z (M+H) = 1227.65.

[1056] <Synthesis Example (5): Synthesis of Compound (1-37)>

[1057] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-37) (1.3 g, yield 10%).

[1058] [Chemistry 217]

[1059]

[1060] The target product was confirmed by APCI-MS with m / z (M+H) = 1295.81.

[1061] <Synthesis Example (6): Synthesis of Compound (1-41)>

[1062] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-41) (2.1 g, yield 17%).

[1063] [Chemistry 218]

[1064]

[1065] The target product was confirmed by APCI-MS with m / z (M+H) = 1251.60.

[1066] <Synthesis Example (7): Synthesis of Compound (1-77)>

[1067] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-77) (1.1 g, yield 8%).

[1068] [Chemistry 219]

[1069]

[1070] The target product was confirmed by APCI-MS with m / z (M+H) = 1374.57.

[1071] <Synthesis Example (8): Synthesis of Compound (1-118)>

[1072] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-118) (2.1 g, yield 18%).

[1073] [Chemistry 220]

[1074]

[1075] The target product was confirmed by APCI-MS with m / z (M+H) = 1175.62.

[1076] <Synthesis Example (9): Synthesis of Compound (1-158)>

[1077] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-158) (1.2 g, yield 11%).

[1078] [Chemistry 221]

[1079]

[1080] The target product was confirmed by APCI-MS to be m / z (M+H) = 1072.46.

[1081] <Synthesis Example (10): Synthesis of Compound (1-231)>

[1082] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-231) (1.3 g, yield 9%).

[1083] [Chemistry 222]

[1084]

[1085] The target product was confirmed by APCI-MS with m / z (M+H) = 1435.64.

[1086] <Synthesis Example (11): Synthesis of Compound (1-338)>

[1087] In the same manner as in Synthesis Example (1), compound (1-338) (1.4 g, yield 10%) was obtained.

[1088] [Chemistry 223]

[1089]

[1090] The target product was confirmed by APCI-MS with m / z (M+H) = 1407.61.

[1091] <Synthesis Example (12): Synthesis of Compound (1-446)>

[1092] Under nitrogen atmosphere, 1.60M tert-butyllithium pentane solution (31.2ml) was added to a flask containing the intermediate (Int-1-446) (13.9g) and tert-butylbenzene (70ml) at 0°C. After the addition was completed, the temperature was raised to 70°C and stirred for 0.5 hours, and the components with a boiling point lower than that of tert-butylbenzene were distilled off under reduced pressure. The mixture was cooled to -50°C and added with boron tribromide (12.6g), and the temperature was raised to room temperature and stirred for 0.5 hours. Thereafter, the mixture was cooled to 0°C again and N,N-diisopropylethylamine (8.6mL) was added, and the mixture was stirred at room temperature until the heat subsided, and then the temperature was raised to 100°C and heated and stirred for 1 hour. The reaction solution was cooled to room temperature, and an aqueous sodium acetate solution cooled by an ice bath was added, followed by toluene for separation. After the organic layer was concentrated, it was purified using a silica gel short column (eluent: toluene / heptane = 2 / 1 (volume ratio)). The obtained crude product was recrystallized from toluene, thereby obtaining Compound (1-446) (0.7 g, yield 5%).

[1093] [Chemistry 224]

[1094]

[1095] The target product was confirmed by APCI-MS with m / z (M+H) = 1338.56.

[1096] <Synthesis Example (13): Synthesis of Compound (1-456)>

[1097] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-456) (1.2 g, yield 10%).

[1098] [Chemistry 225]

[1099]

[1100] The target product was confirmed by APCI-MS with m / z (M+H) = 1243.67.

[1101] <Synthesis Example (14): Synthesis of Compound (1-463)>

[1102] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-463) (1.3 g, yield 10%).

[1103] [Chemistry 226]

[1104]

[1105] The target product was confirmed by APCI-MS with m / z (M+H) = 1321.62.

[1106] <Synthesis Example (15): Synthesis of Compound (1-476)>

[1107] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-476) (1.8 g, yield 14%).

[1108] [Chemistry 227]

[1109]

[1110] The target product was confirmed by APCI-MS with m / z (M+H) = 1305.55.

[1111] <Synthesis Example (16): Synthesis of Compound (1-516)>

[1112] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-516) (1.1 g, yield 10%).

[1113] [Chemistry 228]

[1114]

[1115] The target product was confirmed by APCI-MS with m / z (M+H) = 1114.68.

[1116] <Synthesis Example (17): Synthesis of Compound (1-528)>

[1117] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-528) (1.4 g, yield 11%).

[1118] [Chemistry 229]

[1119]

[1120] The target product was confirmed by APCI-MS to be m / z (M+H) = 1294.60.

[1121] <Synthesis Example (18): Synthesis of Compound (1-531)>

[1122] The same procedure as in Synthesis Example (1) was carried out to obtain Compound (1-531) (1.3 g, yield 10%).

[1123] [Chemistry 230]

[1124]

[1125] The target product was confirmed by APCI-MS with m / z (M+H) = 1291.77.

[1126] The following comparative compounds (Ref-1-1) to (Ref-1-6) were synthesized according to the method described in Korean Patent Publication No. 2022-0069866, International Publication No. 2020 / 200884, or International Publication No. 2020 / 022770.

[1127] [Chemistry 231]

[1128]

[1129] Comparative compound (Ref-1-5) and compounds (1-547) to (1-556) and comparative compound (Ref-1-6) were synthesized according to Synthesis Example (17), and (1-722) to (1-731) were synthesized according to Synthesis Example (16). The synthesized compounds were confirmed to be the target compounds based on the m / z (M+) observed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (Table 1).

[1130] [Table 1]

[1131] Compound m / z Comparative compounds (Ref-1-5) 756.46 Comparative compounds (Ref-1-6) 740.49 Compound (1-547) 1129.7 Compound (1-548) 1241.8 Compound (1-549) 1237.7 Compound (1-550) 1341.8 Compound (1-551) 1235.6 Compound (1-552) 1001.4 Compound (1-553) 1169.6 Compound (1-554) 1258.6 Compound (1-555) 1238.6 Compound (1-556) 1238.6 Compound (1-722) 1222.7 Compound (1-723) 1262.6 Compound (1-724) 1334.8 Compound (1-725) 1330.8 Compound (1-726) 1374.7 Compound (1-727) 1328.7 Compound (1-728) 1446.9 Compound (1-729) 1242.6 Compound (1-730) 1298.7 Compound (1-731) 1354.8

[1132] <<Manufacturing and evaluation of organic EL elements>>

[1133] Using the synthesized compounds of the present invention and comparative compounds, organic EL devices of TTF, TAF, and PSF were produced.

[1134] <TTF structure: Example 1-1-1 to Example 1-1-18 and Comparative Example 1-1-1 to Comparative Example 1-1-4>

[1135] ITO (120 nm) / HI (40 nm) / HAT-CN (5 nm) / HT-1 (45 nm) / HT-2 (10 nm) / BH: each compound listed in Table 2 (97: 3) (25 nm) / ET-1 (5 nm) / ET-2: Liq (1: 1) (25 nm) / LiF (1 nm) / Al (100 nm)

[1136] The chemical structures of the compounds used in the production of the element are shown below.

[1137] [Chemistry 232]

[1138]

[1139] A 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Opto Science Co., Ltd.) on which ITO film having a thickness of 180 nm formed by sputtering was polished to 120 nm was used as a transparent support substrate. The transparent support substrate was fixed on a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing HI, HAT-CN, HT-1, HT-2, BH, each compound described in Table 2, ET-1 and ET-2, and an aluminum nitride vapor deposition boat containing Liq, LiF and aluminum were installed.

[1140] The following layers were formed in sequence on the ITO film of the transparent supporting substrate. The vacuum chamber was depressurized to 5×10 -4Pa, first, HI is heated and evaporated in a manner to make the film thickness 40nm, then HAT-CN is heated and evaporated in a manner to make the film thickness 5nm, then HT-1 is heated and evaporated in a manner to make the film thickness 45nm, then HT-2 is heated and evaporated in a manner to make the film thickness 10nm, to form a hole layer containing four layers. Then, BH and each compound described in Table 2 are heated simultaneously, and evaporated in a manner to make the film thickness 25nm to form a light-emitting layer. The evaporation speed is adjusted in a manner such that the mass ratio of BH to each compound described in Table 2 is approximately 97 to 3. Furthermore, ET-1 is heated and evaporated in a manner to make the film thickness 5nm, then ET-2 and Liq are heated simultaneously, and evaporated in a manner to make the film thickness 25nm to form an electronic layer containing two layers. The evaporation speed is adjusted in a manner such that the mass ratio of ET-2 to Liq is approximately 50 to 50. The deposition rate of each layer is 0.01 nm / sec to 1 nm / sec. Thereafter, LiF is heated and vapor-deposited at a deposition rate of 0.01 nm / sec to 0.1 nm / sec so as to have a film thickness of 1 nm, and then aluminum is heated and vapor-deposited so as to have a film thickness of 100 nm to form a cathode, thereby obtaining an organic EL element.

[1141] <TAF structure: Example 2-1-1 to Example 2-1-18, Comparative Example 2-1-1 to Comparative Example 2-1-4>

[1142] ITO (50 nm) / HAT-CN (10 nm) / HT-1 (60 nm) / SiCzCz (5 nm) / SiCzCz: SiTrzCz2: TADF-1: each compound listed in Table 2 (60: 26: 13: 1) (35 nm) / mSiTrz (5 nm) / mSiTrz: Liq (1: 1) (30 nm) / LiF (1 nm) / Al (100 nm)

[1143] A glass substrate of 26 mm × 28 mm × 0.7 mm (manufactured by Opto Science Co., Ltd.) on which ITO film having a thickness of 200 nm was formed by sputtering and polished to 50 nm was used as a transparent support substrate. The transparent support substrate was fixed on a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing HAT-CN, HT-1, SiCzCz, SiTrzCz2, the compounds described in Table 2, mSiTrz and Liq, and a tungsten vapor deposition boat containing LiF and aluminum, respectively, were installed.

[1144] The following layers were formed in sequence on the ITO film of the transparent supporting substrate. The vacuum chamber was depressurized to 5×10-4 Pa, first, HAT-CN is heated and evaporated in a manner that the film thickness becomes 10nm to form a hole injection layer. Then, HT-1 is heated and evaporated in a manner that the film thickness becomes 60nm to form a hole transport layer 1, and then SiCzCz is heated and evaporated in a manner that the film thickness becomes 5nm to form a hole transport layer 2. Next, SiCzCz, SiTrzCz2, (TADF-1) and each compound recorded in Table 2 are heated at the same time, and evaporated in a manner that the film thickness becomes 35nm to form a light-emitting layer. The evaporation speed is adjusted in a manner that the mass ratio of SiCzCz, SiTrzCz2, (TADF-1) and each compound recorded in Table 2 is approximately 60 to 26 to 13 to 1. Next, mSiTrz is heated and vapor-deposited in a manner to make the film thickness of 5nm to form an electron transport layer 1, and then mSiTrz and Liq are heated and vapor-deposited in a manner to make the film thickness of 30nm to form an electron transport layer 2. The vapor deposition rate is adjusted so that the mass ratio of SiTrz to Liq is approximately 1 to 1. The vapor deposition rate of each layer is 0.01nm / second to 1nm / second. Thereafter, LiF is heated and vapor-deposited at a vapor deposition rate of 0.01nm / second to 0.1nm / second in a manner to make the film thickness of 1nm, and then aluminum is heated and vapor-deposited in a manner to make the film thickness of 100nm to form a cathode, thereby obtaining an organic EL element. At this time, the vapor deposition rate of aluminum is adjusted to 1nm / second to 10nm / second. In addition, SiCzCz of the light-emitting layer corresponds to the hole-transporting host material (compound (HH-1-115)), and SiTrzCz2 corresponds to the electron-transporting host material (compound (EH-1-99)).

[1145] <PSF structure: Example 3-1-1 to Example 3-1-38, Comparative Example 3-1-1 to Comparative Example 3-1-6>

[1146] ITO (50nm) / HAT-CN (10nm) / HT-1 (60nm) / SiCzCz (5nm) / SiCzCz: SiTrzCz2: PtON7: Each compound listed in Table 2 (60:26:13:1) (35nm) / mSiTrz (5nm) / mSiTrz: Liq (1:1) (30nm) / LiF (1nm) / Al (100nm)

[1147] The TAF structure (TADF-1) was replaced with PtON7, and an element was produced in the same manner.

[1148] The chemical structures of the compounds used in the production of the above-mentioned elements are shown below.

[1149] [Chemistry 233]

[1150]

[1151] [evaluate]

[1152] Evaluation items include driving voltage (V), emission wavelength (nm), Commission Internationale de L'Eclairage (CIE) chromaticity (x, y), external quantum efficiency (%), maximum wavelength (nm) and half-value width (nm) of emission spectrum. These evaluation items can be measured using, for example, 1000 cd / m 2 The value when emitting light.

[1153] The quantum efficiency of a light-emitting element includes internal quantum efficiency and external quantum efficiency. The internal quantum efficiency indicates the proportion of external energy injected into the light-emitting layer of the light-emitting element as electrons (or holes) that is purely converted into photons. On the other hand, the external quantum efficiency is calculated based on the amount of photons released to the outside of the light-emitting element. A portion of the photons generated in the light-emitting layer are absorbed by the inside of the light-emitting element or continuously reflected without being released to the outside of the light-emitting element, so the external quantum efficiency is lower than the internal quantum efficiency.

[1154] The spectral radiance (luminescence spectrum) and external quantum efficiency were measured as follows. A voltage / current generator R6144 manufactured by Advantest was used to apply a voltage so that the device brightness reached 1000 cd / m 2 The element emits light by applying a voltage of . Using a spectroradiometer SR-3AR manufactured by TOPCON, the spectral radiance brightness in the visible light region is measured from a direction perpendicular to the light-emitting surface. Assuming that the light-emitting surface is a completely diffuse surface, the value of the spectral radiance brightness of each wavelength component measured is divided by the wavelength energy and multiplied by π to obtain the number of photons at each wavelength. Then, the number of photons is accumulated in the observed full wavelength region and set as the total number of photons released from the element. The value obtained by dividing the applied current value by the elementary charge is set as the number of carriers injected into the element, and the value obtained by dividing the total number of photons released from the element by the number of carriers injected into the element is the external quantum efficiency. In addition, the half-value width of the luminescence spectrum is calculated as the width between the upper and lower wavelengths where the maximum luminescence wavelength is set as the center and its intensity becomes 50%.

[1155] The ITO electrode was used as the anode and the LiF / aluminum electrode was used as the cathode. A DC voltage was applied and the 1000 cd / m 2Characteristics during luminescence. In addition, for the TTF structure element, the time (lifetime) to maintain a brightness of more than 95% of the initial brightness is measured, and for the TAF structure and PSF structure elements, the time (lifetime) to maintain a brightness of more than 50% of the initial brightness is measured. In addition, the luminescence peaks of the elements are all in the range of 450nm to 470nm.

[1156] The results are shown in Table 2.

[1157] [Table 2]

[1158]

[1159]

[1160]

[1161] The obtained results show that the element of the embodiment has higher efficiency and longer life than the element of the comparative example having a corresponding skeleton.

[1162] [Industrial Applicability]

[1163] The polycyclic aromatic compound of the present invention is effectively used as a material for an organic device, 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 having a long life, a low driving voltage and a high luminous efficiency, particularly a long life and a high luminous efficiency, can be obtained.

Claims

1. A polycyclic aromatic compound having a structure consisting of one or more structural units represented by formula (1); [Chemistry 1] 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, in, At least one selected from the group consisting of the A ring, the B ring and the C ring in the structure contains at least one group represented by formula (G) as a substituent, [Chemistry 2] In formula (G), The D ring and the E ring are each independently a substituted or unsubstituted aryl ring, a substituted or unsubstituted heteroaryl ring, wherein any one of them may be a substituted or unsubstituted cycloalkane ring, # indicates the bonding position to the aryl ring or heteroaryl ring in the A ring, B ring or C ring, Ar is each independently a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, Wherein, at least one of Ar in the structure is a monovalent group represented by formula (Ar), [Chemistry 3] In formula (Ar), * indicates the bonding position to the nitrogen atom, R g1 ~R g4 are each independently hydrogen or a substituent, R g1 ~R g4 The two adjacent groups in the group may be bonded to each other and, together with the benzene ring to which they are bonded, form a substituted or unsubstituted aryl ring or a substituted or unsubstituted heteroaryl ring, Z are each independently -C(-R Z )=or-N=,R Z are independently hydrogen or a substituent, at least one set of adjacent -C(-R Z )=Z can be in R Z They are bonded to each other to form a ring, Ar other than the monovalent group represented by formula (Ar) may be bonded to at least one of the A ring, the B ring, and the C ring via a linking group or a single bond. At least one of the aryl rings or heteroaryl rings in the structure may be condensed by at least one cycloalkane, the cycloalkane may have a substituent, and at least one -CH2- in the cycloalkane may be substituted by -O-, In the structure, at least one hydrogen may be replaced by deuterium, and at least one nitrogen may be replaced by nitrogen-15( 15 N) substituted, at least one sulfur may be replaced by sulfur-33( 33 S), sulfur-34 ( 34 S) or sulfur-36( 36 S), at least one oxygen may be replaced by oxygen-17( 17 O) or oxygen-18 ( 18 O) substituted, at least one carbon may be substituted by carbon-13 ( 13 C) substituted, at least one boron may be substituted by boron-11 ( 11 B) Replacement.

2. The polycyclic aromatic compound according to claim 1, wherein At least one Z is R Z -C(-R Z )=, or at least one set of adjacent ones as -C(-R Z )=Z in R Z are bonded to each other to form a ring, wherein any adjacent Z is not in R Z When the substituents R Z When the number of substituents is 4 or less except hydrogen atoms, at least two Z are R Z -C(-R Z )=.

3. The polycyclic aromatic compound according to claim 2, wherein At least one R Z is at least one substituent selected from the substituent group ZA1, and can be combined with the adjacent R Z The substituent group ZA1 may be substituted by at least one substituent selected from the substituent group ZB1; Substituent group ZA1: aryl, heteroaryl, alkyl, cycloalkyl, arylalkyl, diarylamino, diheteroarylamino, arylheteroarylamino, triarylsilyl, diarylmonoalkylsilyl, monoaryldialkylsilyl, trialkylsilyl, monoarylmonoalkylamino, dialkylamino, diphenylphosphoryl, aryloxy, arylthio and diarylboryl; Substituent group ZB1: aryl, heteroaryl, alkyl, cycloalkyl, cyano and halogen.

4. The polycyclic aromatic compound according to claim 3, wherein At least one R Z is at least one substituent selected from the following groups, and can be combined with the adjacent R Z Bond to form a ring: Aryl, which may be substituted by at least one substituent selected from the substituent group ZB1; Heteroaryl may be substituted with at least one substituent selected from the substituent group ZB1; Cycloalkyl may be substituted by at least one substituent selected from the substituent group ZB1; Arylalkyl may be substituted with at least one substituent selected from the substituent group ZB1; The diarylamino group may be substituted with at least one substituent selected from the substituent group ZB1; The diheteroarylamino group may be substituted with at least one substituent selected from the substituent group ZB1; Arylheteroarylamino may be substituted with at least one substituent selected from the substituent group ZB1; The triarylsilyl group may be substituted with at least one substituent selected from the substituent group ZB1; The aryloxy group may be substituted by at least one substituent selected from the substituent group ZB1; An arylthio group may be substituted with at least one substituent selected from the substituent group ZB1; and The diarylboryl group may be substituted with at least one substituent selected from the substituent group ZB1.

5. The polycyclic aromatic compound according to claim 4, wherein The monovalent group represented by formula (Ar) is any of the following, [Chemistry 4] [Chemistry 5] [Chemistry 6] 6. The polycyclic aromatic compound according to claim 5, which is represented by any one of the following structural formulas: [Chemistry 8] [Chemistry 9] In the formula, Me is a methyl group, tBu is a tert-butyl group, Cy is a cyclohexyl group, and Ad is a 1-adamantyl group.

7. The polycyclic aromatic compound according to claim 1, wherein At least one of the A ring, the B ring, and the C ring is a substituted or unsubstituted heteroaryl ring.

8. The polycyclic aromatic compound according to claim 7, which is represented by any one of the following structural formulas: [Chemistry 10] [Chemistry 11] [Chemistry 12] In the formula, Me is a methyl group, tBu is a tert-butyl group, Cy is a cyclohexyl group, and Ad is a 1-adamantyl group.

9. A material for an organic device, comprising the polycyclic aromatic compound according to any one of claims 1 to 8. 10 . An organic electroluminescent element, comprising: a pair of electrodes including an anode and a cathode; and an organic layer disposed between the pair of electrodes, wherein the organic layer contains the polycyclic aromatic compound according to claim 1 .

11. The organic electroluminescent element according to claim 10, wherein: The organic layer is a light-emitting layer.

12. The organic electroluminescent element according to claim 11, wherein The light-emitting layer includes at least one selected from the group consisting of an auxiliary dopant and a phosphorescent material.

13. A display device or a lighting device, comprising the organic electroluminescent element according to claim 10.

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