Compound, light-emitting material and light-emitting device

Abstract

To provide a compound useful as a light-emitting element having high emission efficiency.SOLUTION: Using a compound represented by the general formula (A)m-L-(D)n, a light-emitting element having high emission efficiency can be provided, where: L is an (m+n)-valent aromatic linking group; A is a group where Hammett's σp value is positive; D is a group where Hammett's σp value is negative; m is an integer equal to or greater than 1; n is an integer equal to or greater than 2; and two of the multiple occurrences of D have mutually different substituent conditions at specific aromatic rings.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a compound useful as a light-emitting material and a light-emitting device using the same. [Background technology]

[0002] Research into improving the luminous efficiency of light-emitting elements such as organic electroluminescent elements (organic EL elements) has been actively conducted. In particular, various efforts have been made to improve luminous efficiency by newly developing and combining electron transport materials, hole transport materials, and luminescent materials that make up organic electroluminescent elements. Among these efforts, there has also been research into organic electroluminescent elements that use delayed fluorescent materials.

[0003] Delayed fluorescent materials are compounds that undergo reverse intersystem crossing from an excited triplet state to an excited singlet state in an excited state, and then emit fluorescence when returning from that excited singlet state to the ground state. Fluorescence via this pathway is observed later than fluorescence from the excited singlet state (normal fluorescence) that arises directly from the ground state, hence the term delayed fluorescence. For example, when a light-emitting compound is excited by carrier injection, the probability of the occurrence of the excited singlet state and the excited triplet state is statistically 25%:75%, so there is a limit to the improvement in luminous efficiency when relying solely on fluorescence from the directly arisen excited singlet state. On the other hand, delayed fluorescent materials can utilize not only the excited singlet state but also the excited triplet state for fluorescence emission via the above-mentioned reverse intersystem crossing pathway, resulting in higher luminous efficiency than normal delayed fluorescent materials.

[0004] As such delayed fluorescent materials, Patent Document 1 proposes a benzene derivative having a heteroaryl group such as a carbazolyl group or a diphenylamino group and at least two cyano groups, and it has been confirmed that high luminous efficiency was obtained in an organic EL device using the benzene derivative in the light-emitting layer. Furthermore, Non-Patent Document 1 reports that a carbazolyldicyanobenzene derivative (hereinafter referred to as "4CzIPN") represented by the following formula is a thermally activated delayed fluorescent material, and that an organic electroluminescence device using 4CzIPN has achieved high internal EL quantum efficiency. Furthermore, Non-Patent Document 2 reports that high luminous efficiency and high durability have been achieved by optimizing the structure of an organic electroluminescence device using 4CzIPN.

[0005] [ka] [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-43541 [Non-patent literature]

[0007] [Non-Patent Document 1] H. Uoyama, et al., Nature 492, 234 (2012) [Non-patent document 2] H. Nakanotani, et al., Scientific Reports, 3, 2127 (2013) Summary of the Invention [Problem to be solved by the invention]

[0008] As mentioned above, Patent Document 1 and Non-Patent Documents 1 and 2 report that the delayed fluorescent material 4CzIPN is useful as a material for light-emitting devices. This compound has a structure in which a cyano group with acceptor properties and a carbazolyl group with donor properties are bonded to a core benzene ring, and this structure controls the spatial positions of the HOMO and LUMO, thereby improving the luminescence efficiency. However, when the present inventors investigated the luminescence process of 4CzIPN, they found that it was not fully optimal and that there was room for significant improvement in luminescence efficiency by further controlling the structure of the donor group bonded to the core benzene ring.

[0009] Under these circumstances, the present inventors have conducted extensive research with the aim of finding and generalizing materials with higher luminous efficiency, and have deduced a general formula for a compound useful as a luminescent material, and have pursued intensive research with the aim of generalizing the configuration of light-emitting devices with higher luminous efficiency. [Means for solving the problem]

[0010] As a result of intensive research to achieve the above object, the present inventors have found that compounds having a structure in which a donor group and an acceptor group are bonded to an aromatic ring of a core, and in which the substituent conditions (number of substituents, substitution position, and substituent structure) between the two donor groups are different, have superior luminescence properties to those of 4CzIPN. They have also demonstrated that the use of such compounds as luminescent materials can provide light-emitting devices with extremely high luminous efficiency. The present invention has been proposed based on these findings and specifically has the following configuration.

[0011] [1] A compound represented by the following general formula (1): [ka] [In general formula (1), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value or a phenyl group, D is a group having a negative Hammett σp value (excluding a phenyl group), m is an integer of 1 or more, and n is an integer of 2 or more. When m is 2 or more, the multiple As may be the same or different from one another. Two of the multiple Ds are groups having different structures but containing a common aromatic ring.] [2] The compound according to [1], wherein two of the plurality of Ds are groups containing a heteroatom. [3] The compound according to [2], wherein two of the plurality of Ds are groups containing a structure in which two or more aromatic rings are bonded to a heteroatom. [4] The compound according to [3], wherein two of the plurality of Ds comprise a diarylamine structure (provided that the two aryl groups constituting the diarylamine structure may be bonded to each other). [5] The compound according to [4], wherein the diarylamine structure is a carbazole structure. [6] The compound according to any one of [1] to [5], wherein m is 1. [7] The compound according to any one of [1] to [5], wherein m is 2 or more. [8] The compound according to any one of [1] to [7], wherein two of the plurality of Ds satisfy the following condition (a) or the following condition (b): Condition (a) Both of the two Ds have an aromatic ring containing an atom bonded to L, and the aromatic ring is common between the two Ds, but at least one of the conditions of the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring is different. Condition (b)

[0046] Each of the two Ds has a linking group bonded to L and one aromatic ring bonded to the linking group, and the two Ds share the same linking group and aromatic ring bonded to the linking group, but differ from each other in at least one of the following conditions: the number of substituents on the aromatic ring, the positions at which the substituents are substituted on the aromatic ring, and the structure of the substituents substituted on the aromatic ring.

[0047] Each of the two Ds has a linking group bonded to L and two or more aromatic rings bonded to the linking group, and the two Ds share the same linking group, the number of aromatic rings bonded to the linking group, and the multiple aromatic rings, but differ from each other in at least one of the combinations of aromatic rings shared between the two Ds: the number of substituents on the aromatic ring, the positions at which the substituents are substituted on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. [9] The compound according to [8], wherein two of the plurality of Ds satisfy the condition (a).

[10] The compound according to any one of [1] to [9], wherein two of the plurality of Ds are groups represented by the following general formula (2): [ka] [In general formula (2), R 11 ~R 19 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 11 ~R 19 One of these is the bonding position to L.]

[11] R in the general formula (2) 19 is the bonding position to L.

[12] One of two of the plurality of Ds is R in the general formula (2). 11 ~R 18 At least one of the Ds is a substituent, and the other two of the Ds are R 11 ~R 18 wherein one of the two D's that is a substituent corresponds to a hydrogen atom.

[13] One of two of the plurality of Ds is R in the general formula (2). 13 and R 16 The compound according to any one of

[10] to

[12] , wherein at least one of the following is a substituent.

[14] The compound according to

[12] or

[13] , wherein the substituent is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

[15] The compound according to [1], wherein the compound represented by the general formula (1) is a compound represented by the following general formula (10): [ka] [In the general formula (10), A 1 represents a group with a positive Hammett σp value. 1 ~R 5 each independently represents a hydrogen atom, a group having a positive Hammett σp value, or a group having a negative Hammett σp value; R 1 ~R 5 At least two of the R groups have a negative Hammett σp value (except for the phenyl group). 1 ~R 6 When one or more of the groups has a positive Hammett σp value, A 1 The Hammett σp value is positive and R 1 ~R 6 Among these, the groups having a positive Hammett σp value may be the same or different.]

[16] R 1 ~R 5 The compound according to

[15] , wherein two of the groups having negative Hammett σp values ​​satisfy the following condition (a) or condition (b): Condition (a) The two groups having negative Hammett σp values ​​each have an aromatic ring containing an atom bonded to the benzene ring of general formula (10), and the two groups having negative Hammett σp values ​​have the same aromatic ring, but differ from each other in at least one of the following conditions: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. Condition (b) The two groups with negative Hammett σp values ​​each have a linking group bonded to the benzene ring of general formula (10) and one aromatic ring bonded to the linking group, and the two groups with negative Hammett σp values ​​have the linking group and the aromatic ring bonded to the linking group in common, but are different from each other in at least one condition: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. The two groups having a negative Hammett σp value each have a linking group bonded to a benzene ring of general formula (10) and two or more aromatic rings bonded to the linking group, and the linking group, the number of aromatic rings bonded to the linking group, and the number of aromatic rings are common between the two groups having a negative Hammett σp value, but in at least one combination of aromatic rings common between the two groups having a negative Hammett σp value, at least one of the conditions of the number of substituents substituted on the aromatic ring, the position of substitution by the substituent on the aromatic ring, and the structure of the substituent substituted on the aromatic ring is different from each other.

[17] R in the general formula (10) 1 and R 4 Combination of, and,R 2 and R 5 The compound according to

[16] , wherein at least one of the combinations satisfies the condition (a) or (b).

[18] R in the general formula (10) 1 ~R 5 The compound according to any one of

[15] to

[17] , wherein is a group (excluding a phenyl group) having a negative Hammett σp value.

[19] The compound according to [1], wherein the compound represented by the general formula (1) is a compound represented by the following general formula (11): [ka] [In the general formula (11), A X1 represents a group with a positive Hammett σp value. X11 ~R X14 each independently represents a hydrogen atom, a group having a positive Hammett σp value, or a group having a negative Hammett σp value; R X11 ~R X14At least two of the R groups have a negative Hammett σp value (except for the phenyl group). X11 ~R X14 When one or more of the Hammett σp values ​​are positive, A X1 The Hammett σp value is positive and R X11 ~R X14 Among these, the groups having a positive Hammett σp value may be the same or different.]

[20] R X11 ~R X14 The compound according to

[19] , wherein two of the groups having negative Hammett σp values ​​satisfy the following condition (a) or condition (b): Condition (a) The two groups having negative Hammett σp values ​​each have an aromatic ring containing an atom bonded to the benzene ring of general formula (10), and the two groups having negative Hammett σp values ​​have the same aromatic ring, but differ from each other in at least one of the following conditions: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. Condition (b) The two groups with negative Hammett σp values ​​each have a linking group bonded to the benzene ring of general formula (10) and one aromatic ring bonded to the linking group, and the two groups with negative Hammett σp values ​​have the linking group and the aromatic ring bonded to the linking group in common, but are different from each other in at least one condition: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. The two groups with negative Hammett σp values ​​each have a linking group bonded to a benzene ring of general formula (10) and two or more aromatic rings bonded to the linking group, and the linking group, the number of aromatic rings bonded to the linking group, and the number of aromatic rings are common between the two groups with negative Hammett σp values. However, in at least one combination of aromatic rings common between the two groups with negative Hammett σp values, at least one of the conditions of the number of substituents substituted on the aromatic ring, the position of substitution by the substituent on the aromatic ring, and the structure of the substituent substituted on the aromatic ring is different from each other.

[21] A light-emitting material comprising the compound according to any one of [1] to

[20] .

[22] A light-emitting device comprising the compound according to any one of [1] to

[20] .

[23] A method for producing a compound represented by general formula (1), comprising a step of reacting a compound represented by general formula (18) below with a compound represented by general formula (21) below and a compound represented by general formula (22) below: [ka] [In general formula (18), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value or a phenyl group, X is a halogen atom, m is an integer of 1 or more, and n is an integer of 2 or more. When m is 2 or more, multiple As may be the same or different from one another. Multiple Xs may be the same or different from one another.] [ka] [In the general formula (21), D 1 is a group with a negative Hammett σp value (except for the phenyl group). [ka] [In the general formula (22), D 2 is a group with a negative Hammett σp value (except for the phenyl group), and D 1 is a group having a structure different from that of [ka] [In general formula (1), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value or a phenyl group, D is a group having a negative Hammett σp value (excluding a phenyl group), m is an integer of 1 or more, and n is an integer of 2 or more. When m is 2 or more, the multiple As may be the same or different from one another. Two of the multiple Ds are groups containing a common aromatic ring and have different structures from one another.]

[24] A method for producing a compound represented by general formula (1), comprising a step of reacting a compound represented by general formula (19) below with a compound represented by general formula (22) below: [ka] [In the general formula (19), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value or a phenyl group, and D 1 is a group having a negative Hammett σp value (excluding phenyl groups), m is an integer of 1 or more, and n is an integer of 1 or more. When m is 2 or more, multiple A's may be the same or different. When n is 2 or more, multiple D's 1 may be the same or different, X is a halogen atom, and p is an integer of 1 or more and less than n. [ka] [In the general formula (22), D 2 is a group with a negative Hammett σp value (except for the phenyl group), and D 1 is a group having a structure different from that of [ka] [In general formula (1), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value or a phenyl group, D is a group having a negative Hammett σp value (excluding a phenyl group), m is an integer of 1 or more, and n is an integer of 2 or more. When m is 2 or more, the multiple As may be the same or different from one another. Two of the multiple Ds are groups containing a common aromatic ring and have different structures from one another.]

[25] A compound represented by the following general formula (19): [ka] [In the general formula (19), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value or a phenyl group, and D 1is a group having a negative Hammett σp value (excluding phenyl groups), m is an integer of 1 or more, and n is an integer of 1 or more. When m is 2 or more, multiple A's may be the same or different. When n is 2 or more, multiple D's 1 may be the same or different. X is a halogen atom, and p is an integer of 1 or more and less than n. However, compounds having the following structure are not included in general formula (19). [ka]

[26] The compound according to

[25] , wherein the halogen atom is a fluorine atom.

[27] D 1 The compound according to

[25] or

[26] , wherein at least one of the above is a diarylamino group (provided that the two aryl groups constituting the diarylamino group may be bonded to each other).

[28] The compound according to any one of

[25] to

[27] , wherein at least one of A is a cyano group. [Effects of the Invention]

[0012] The compound of the present invention has high luminous efficiency and is useful as a light-emitting material. A light-emitting device using the compound of the present invention as a material can achieve extremely high luminous efficiency. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a schematic cross-sectional view showing an example of a layer structure of an organic electroluminescence element. [Figure 2] 1 shows absorption spectra of organic photoluminescence devices using compounds 1 to 4 and 6. [Figure 3] 1 shows the fluorescence spectra of organic photoluminescence devices using compounds 1 to 4 and 6. [Figure 4] 1 shows transient decay curves of light emission from organic photoluminescence devices using compounds 1 to 4 and 6. [Figure 5]1 shows phosphorescence spectra of organic photoluminescence devices using compounds 1 to 4 and 6. [Figure 6] 1 shows fluorescence spectra of organic electroluminescence devices using compounds 3 and 6 and comparative compound 1. [Figure 7] 1 is a graph showing the current density-voltage characteristics of organic electroluminescence devices using Compounds 3 and 6 and Comparative Compound 1. [Figure 8] 1 is a graph showing the current density-external quantum efficiency characteristics of organic electroluminescence devices using Compounds 3 and 6 and Comparative Compound 1. [Figure 9] 1 is a graph showing the change over time in luminance of organic electroluminescence devices using Compounds 3 and 6 and Comparative Compound 1. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in detail below. The following description of the constituent elements may be based on typical embodiments or specific examples of the present invention, but the present invention is not limited to such embodiments or specific examples. In this specification, a numerical range expressed using "to" means a range including the numerical values ​​before and after "to" as the lower and upper limits. In addition, the isotopes of hydrogen atoms present in the molecules of the compounds used in the present invention are not particularly limited, and for example, it is possible to use a compound in which all hydrogen atoms in the molecule are isotopic. 1 H, or part or all of 2 It may also be H (deuterium D).

[0015] [Compound represented by general formula (1)] The compound of the present invention is a compound represented by the following general formula (1). [ka] In general formula (1), L is an aromatic linking group having a valence of m+n. m and n correspond to the number of As and Ds bonded to the aromatic linking group, respectively. The aromatic linking group represented by L is composed of an aromatic ring, and among the positions on the aromatic ring that can be substituted with a substituent, As replace hydrogen atoms at m positions and are bonded to carbon atoms, and D replaces hydrogen atoms at n positions and are bonded to carbon atoms. That is, the aromatic linking group represented by L is composed of an aromatic ring from which m+n hydrogen atoms have been removed. Among the positions on the aromatic ring that can be substituted with a substituent, all or some may be substituted with A or D, but it is preferred that all of the substitutable positions on the aromatic ring be substituted with A or D. The aromatic ring constituting the aromatic linking group represented by L may be an aromatic ring made of hydrocarbon (hereinafter referred to as "aromatic hydrocarbon ring") or an aromatic ring containing a heteroatom (hereinafter referred to as "aromatic heterocycle"). The group that can be substituted by a substituent on the aromatic hydrocarbon ring is a methine group (-CH=), and examples of the group that can be substituted by a substituent on the aromatic heterocycle include a methine group (-CH=), an imino group (-NH-), etc. The aromatic hydrocarbon ring constituting the aromatic linking group represented by L may be a monocyclic ring, a fused ring in which two or more aromatic hydrocarbon rings are fused, a spiro ring in which two aromatic hydrocarbon rings are connected by a spiro bond, or a linked ring in which two or more aromatic hydrocarbon rings are linked. When two or more aromatic hydrocarbon rings are linked, they may be linked in a linear or branched chain. The number of carbon atoms in the aromatic hydrocarbon ring constituting the aromatic linking group is preferably 6 to 22, more preferably 6 to 18, even more preferably 6 to 14, and even more preferably 6 to 10. Specific examples of the aromatic hydrocarbon ring constituting the aromatic linking group include a benzene ring, a naphthalene ring, a biphenyl ring, and a spirofluorene ring. The aromatic heterocycle constituting the aromatic linking group represented by L may be a monocycle, a fused ring in which one or more heterocycles are fused with an aromatic hydrocarbon ring or an aromatic heterocycle, a spiro ring in which one heterocycle and one aromatic hydrocarbon ring or aromatic heterocycle are connected via a spiro bond, or a linked ring in which one or more aromatic heterocycles are connected with an aromatic hydrocarbon ring or aromatic heterocycle. The number of carbon atoms in the aromatic heterocycle is preferably 5 to 22, more preferably 5 to 18, even more preferably 5 to 14, and even more preferably 5 to 10. The heteroatom constituting the aromatic heterocycle is preferably a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring, a pyridazine ring, a pyrimidine ring, a triazole ring, and a benzotriazole ring. The aromatic ring constituting the aromatic linking group represented by L is more preferably a benzene ring.

[0016] A is a group with a positive Hammett σp value, and D is a group with a negative Hammett σp value. However, the phenyl group is exceptionally included in A but not in D. Here, the "Hammett σp value" was proposed by L.P. Hammett and quantifies the influence of a substituent on the reaction rate or equilibrium of a para-substituted benzene derivative. Specifically, the following equation holds between the substituent in the para-substituted benzene derivative and the reaction rate constant or equilibrium constant: log(k / k0) = ρσp or log(K / K0) = ρσp where k is the rate constant for the benzene derivative without a substituent, k0 is the rate constant for the benzene derivative substituted with a substituent, K is the equilibrium constant for the benzene derivative without a substituent, K0 is the equilibrium constant for the benzene derivative substituted with a substituent, and ρ is a reaction constant determined by the type and conditions of the reaction. For an explanation of the "Hammett σp value" in this invention and the numerical values ​​of each substituent, please refer to the description of σp values ​​in Hansch, C. et al., Chem. Rev., 91, 165-195 (1991). Groups with a negative Hammett σp value tend to exhibit electron-donating (donor) properties, while groups with a positive Hammett σp value tend to exhibit electron-withdrawing (acceptor) properties.

[0017] The aromatic linking group represented by L is bonded with m As. m is an integer of 1 or more, and when m is 2 or more, the multiple As may be the same or different. There is no particular upper limit for m, but it is preferably smaller than n.

[0018] The group having a positive Hammett σp value represented by A is not particularly limited, but examples thereof include groups containing a cyano group, a carbonyl group, or a sulfonyl group, and substituted or unsubstituted heteroaryl groups. Examples of heteroatoms contained in the heteroaryl group include a nitrogen atom, an oxygen atom, a sulfur atom, and a boron atom. Preferably, the heteroaryl group contains at least one nitrogen atom as a ring member. Examples of such heteroaryl groups include groups consisting of a 5- or 6-membered ring containing a nitrogen atom as a ring member, or groups having a structure in which a benzene ring is fused to a 5- or 6-membered ring containing a nitrogen atom as a ring member. Preferred examples of such heteroaryl groups include monovalent groups obtained by removing one hydrogen atom from a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, or a triazine ring, groups having a structure in which these aromatic heterocycles are fused to each other, and groups having a structure in which a benzene ring is fused to these aromatic heterocycles. Furthermore, a monovalent group having a structure in which a benzene ring is fused to a quinone ring or a pyrone ring and in which one hydrogen atom has been removed from the benzene ring is also preferred as a group having a positive Hammett σp value. Here, the benzene ring fused to the quinone ring or the pyrone ring may be substituted with a substituent. Examples of the substituent when the benzene ring fused to the quinone ring or the pyrone ring has a substituent, and when the heteroaryl group has a substituent, include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, a cyano group, a halogen atom, and a heteroaryl group having 5 to 40 carbon atoms. Among these substituents, those that can be substituted by a substituent may be substituted. Furthermore, A includes a phenyl group. When m is 2 or more, the number of cyano groups among the multiple A's can be, for example, 0 to 2, with one cyano group being more preferred than two.

[0019] Specific examples of groups represented by A and having a positive Hammett σp value are given below. However, in the present invention, the groups represented by A and having a positive Hammett σp value should not be interpreted as being limited by these groups. Among the groups exemplified below, those having a ring structure are bonded to L by replacing a hydrogen atom of any one of the methine groups (-CH=) constituting the ring structure. The lines on the left and right of CO in a carbonyl group (-CO-) and the lines on the left and right of SO in a sulfonyl group (-SO2-) each represent a single bond (bond). The carbonyl group (-CO-) and the sulfonyl group (-SO2-) are bonded to L directly through one single bond or via a linking group, and an atomic group is bonded to the other single bond. Examples of the atomic group include a substituted or unsubstituted alkyl group, an aryl group, and a heteroaryl group. The alkyl group preferably has 1 to 20 carbon atoms, the aryl group preferably has 6 to 40 carbon atoms, and the heteroaryl group preferably has 5 to 40 carbon atoms.

[0020] [ka] JPEG0007758385000017.jpg144159

[0021] Next, we will explain D. The aromatic linking group represented by L is bonded with n Ds. n is an integer of 2 or greater, and two of the Ds contain a common aromatic ring but have different structures. The type of the common aromatic ring is not particularly limited, and may be an aromatic hydrocarbon ring or an aromatic heterocycle. For descriptions of the aromatic hydrocarbon ring and the aromatic heterocycle and their preferred ranges, please refer to the corresponding sections in the descriptions of conditions (a) and (b) below. A preferred aromatic ring is a benzene ring, but is not limited thereto. In addition, preferred examples of groups containing an aromatic ring include groups containing a diarylamino structure or a carbazolyl structure, but are not limited thereto. Preferably, two of the Ds are groups containing a heteroatom, and more preferably groups containing a nitrogen atom. Specific structures include groups represented by any of the general formulas (2) to (9) described below.

[0022] Two of the multiple Ds preferably satisfy the following condition (a) or (b). Condition (a) Both of the two Ds have an aromatic ring containing an atom bonded to L, and the aromatic ring is common between the two Ds, but at least one of the following conditions is different between them: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. Condition (b) When two Ds each have a linking group bonded to L and one or more aromatic rings bonded to the linking group, and when both Ds each have one aromatic ring bonded to the linking group, the linking group and the aromatic ring bonded to the linking group are common between the two Ds, but at least one condition is different between the two Ds: the number of substituents substituted on the aromatic ring, the positions on the aromatic ring where the substituents are substituted, and the structure of the substituents substituted on the aromatic ring. When two or more aromatic rings each have two or more linking groups bonded to the linking group, the two Ds each have the same linking group, the number of aromatic rings bonded to the linking group, and the multiple aromatic rings, but at least one of the combinations of aromatic rings common between the two Ds is different between the two Ds: the number of substituents substituted on the aromatic ring, the positions on the aromatic ring where the substituents are substituted, and the structure of the substituents substituted on the aromatic ring. In the following explanation, one of the two Ds that satisfy condition (a) or (b) will be referred to as "one D," and the other will be referred to as "the other D." The two Ds that satisfy condition (a) or (b) ("one D" and "the other D") may be one set of multiple Ds, or two or more sets. In addition, in condition (a), the "aromatic ring containing an atom bonding to L" possessed by one D is referred to as "one aromatic ring," and the "aromatic ring containing an atom bonding to L" possessed by the other D is referred to as "the other aromatic ring." In the condition (b), "when two or more aromatic rings are bonded to the linking group in both of the two Ds, the linking group, the number of aromatic rings bonded to the linking group, and the plurality of aromatic rings are common between the two Ds, but in at least one combination of the aromatic rings common between the two Ds, at least one of the conditions of the number of substituents substituted on the aromatic ring, the position of substitution by the substituent on the aromatic ring, and the structure of the substituent substituted on the aromatic ring are different from each other" means that in one D, a benzene ring and a naphthyl group are bonded to L via a trivalent linking group. For example, in the case where two naphthalene rings are linked, similarly to one D, the other D also has a benzene ring and a naphthalene ring linked to L via a trivalent linking group, and the common combinations of aromatic rings, i.e., the combination of the benzene ring of one D and the benzene ring of the other D, or the combination of the naphthalene ring of one D and the naphthalene ring of the other D, or both of these combinations, differ from each other in at least one condition: the number of substituents on the ring, the position of the substituents on the ring, or the structure of the substituents on the ring. In condition (b), when both Ds have one aromatic ring bonded to the linking group, the "aromatic ring linked to the linking group" possessed by one D is referred to as "one aromatic ring," and the "aromatic ring linked to the linking group" possessed by the other D is referred to as "the other aromatic ring." When two Ds each have two or more aromatic rings bonded to a linking group, one of the "combinations of aromatic rings common to each other" between the two Ds that differ in at least one substituent condition is referred to as "one aromatic ring" and the other as "the other aromatic ring." In the following description, the "number of substituents on the aromatic ring," "positions on the aromatic ring where the substituents are substituted," and "structures of the substituents on the aromatic ring" may be collectively referred to as "substituent conditions."

[0023] The aromatic ring in conditions (a) and (b) may be an aromatic hydrocarbon ring or an aromatic heterocycle, and may be a monocycle or a fused ring. When an aromatic ring forms a connecting ring, the aromatic ring closest to L is the aromatic ring in conditions (a) and (b). The aromatic ring being in common means that the structures of one aromatic ring and the other aromatic ring are all the same except for the number of hydrogen atoms replaced by substituents and the substituent conditions. The linking group in condition (b) may be a divalent linking group linking L to one aromatic ring, or a trivalent or higher linking group linking L to two or more aromatic rings. When two or more aromatic rings are bonded to the linking group, the aromatic rings bonded to the linking group may be the same or different.

[0024] The difference in the substituent conditions on the aromatic ring can be determined as follows. First, the number of substituents on the common aromatic rings (common aromatic rings containing an atom bonded to L, or common aromatic rings connected to L via a linking group) between one D and another D is compared. If the number of substituents is different, the "number of substituents on the aromatic ring" among the above-mentioned substituent conditions is determined to be different. If the number of substituents is the same, the positions (substitution positions) of the aromatic rings where the substituents are substituted are compared. If there is even one different substitution position, the "positions of the aromatic rings where the substituents are substituted" among the above-mentioned substituent conditions is determined to be different. If all substitution positions are the same, the structures of the substituents on the aromatic rings are compared. If at least one of the substituents on the aromatic ring of one D has a different structure from the substituent on the corresponding substitution position of the aromatic ring of another D, the "structure of the substituents on the aromatic ring" among the above-mentioned substituent conditions is determined to be different. Here, the "corresponding substitution position" of the aromatic ring of another D refers to a position on the aromatic ring that is common to the substitution position of one D on the aromatic ring's structural formula. Specifically, when the structural formulas of the aromatic rings of two Ds are superimposed with all substitution positions aligned, the overlapping positions correspond to the "corresponding substitution position." Alternatively, the "corresponding substitution position" refers to a position on the aromatic ring that shares a common position number assigned according to the IUPAC nomenclature. However, if the structural formula of the aromatic ring is linearly symmetric, the overlapping positions upon a 180° rotation around the axis of symmetry are also included in the "corresponding substitution position." The "structures of the substituents substituted on the aromatic rings" are determined to be different when at least one of the substituents substituted on the aromatic ring of one D differs in structure from the substituents substituted on both corresponding positions on the aromatic rings of another D. For example, a substituent substituted on the 3-position of a carbazole ring would be different from both the substituents substituted on the 3-position and the 6-position of the other carbazole ring. "Different substituent structures" means that at least one of the following conditions is different: type of substituent, type and number of atoms constituting the substituent, presence or absence of saturated bonds, chain structure (straight-chain structure, branched structure, branching position in the case of a branched structure), and cyclic structure (number of ring members, aromatic or non-aromatic ring, presence or absence of fused rings). Furthermore, when two substituents substituted on an aromatic ring are bonded to each other to form a ring structure, the two substituents can each be considered as a "substituent" in the substituent condition. For example, when the aromatic ring is a naphthalene ring, the naphthalene ring as a whole can be considered as an "aromatic ring," or it can be considered as a benzene ring substituted with a substituent at adjacent positions. When a naphthalene ring is considered as a benzene ring substituted with a substituent at adjacent positions, it has a common aromatic ring but a different number of substituents from an unsubstituted benzene ring. In the present invention, even when the aromatic rings of interest between two Ds have such a relationship, it is determined that condition (a) or (b) is satisfied. Among these substituent conditions, it is preferable that the "number of substituents substituted on the aromatic ring" differs between one aromatic ring and the other aromatic ring, and it is more preferable that the other aromatic ring is substituted with at least one substituent and is unsubstituted.

[0025] The two Ds satisfying the condition (a) or (b) preferably contain a diarylamine structure (however, the two aryl groups constituting the diarylamine structure may be bonded to each other). In the present invention, the "diarylamine structure" means a structure in which two aryl groups are bonded to a nitrogen atom, and the two aryl groups may be bonded to each other or may be substituted with a substituent. When the aryl group has a substituent, the preferred range and specific examples of the substituent are described in R in general formula (2). 11 ~R 19The preferred ranges and specific examples of the substituents that can be taken can be referred to. The aromatic hydrocarbon ring constituting the aryl group of the diarylamine structure may be a monocyclic ring or a fused ring in which two or more aromatic hydrocarbon rings are fused. The aromatic hydrocarbon ring constituting the aryl group of the diarylamine structure preferably has 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, even more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. Specific examples of the aryl group of the diarylamine structure include a substituted or unsubstituted phenyl group and a substituted or unsubstituted naphthyl group. Furthermore, when two aryl groups of the diarylamine structure are bonded to each other, the two aryl groups may be bonded by a single bond or may be bonded via a linking group. Examples of the linking group connecting the two aryl groups include an oxygen atom, a sulfur atom, and a substituted or unsubstituted alkylene group. When the alkylene group has a substituent, examples of the substituent include a substituted or unsubstituted alkyl group and a substituted or unsubstituted aryl group. Specific examples of the diarylamine structure in which two aryl groups are bonded to each other include a carbazole structure, a phenoxazine structure, a phenothiazine structure, and an acridine structure. It is more preferable that the two Ds satisfying the condition (a) or (b) include a carbazole structure. In a group containing a diarylamine structure, the diarylamine structure may be bonded to L via a single bond, or may be bonded to L via a divalent linking group. The divalent linking group is not particularly limited. The diarylamine structure may be bonded to L or a divalent linking group by replacing a hydrogen atom of one of its two aryl groups with L or a divalent linking group, or its nitrogen atom may be bonded to L or a divalent linking group. However, it is preferable that the nitrogen atom of the diarylamine structure is bonded to L or a divalent linking group, and it is more preferable that the nitrogen atom of the diarylamine structure is directly bonded to L (bonded via a single bond). That is, the diarylamine structure is preferably a diarylamino group (however, the two aryl groups constituting the diarylamine structure may be bonded to each other), and more preferably a diarylamino group bonded to L via a single bond.

[0026] Regarding the relationship between the diarylamine structure and condition (a) or (b), first, when two aryl groups in the diarylamine structure are bonded to each other and one of the aryl groups or the nitrogen atom is bonded to L via a single bond, the entire diarylamine structure corresponds to the aromatic ring in condition (a). When two aryl groups in the diarylamine structure are bonded to each other and one of the aryl groups or the nitrogen atom is linked to L via a divalent linking group, the divalent linking group corresponds to the linking group in condition (b), and the entire diarylamine structure corresponds to the aromatic ring in condition (b). When two aryl groups in the diarylamine structure are not bonded to each other and one of the aryl groups is bonded to L via a single bond, the other aryl group bonded to L via a single bond corresponds to the aromatic ring of condition (a). When the two aryl groups in the diarylamine structure are not bonded to each other and the nitrogen atom thereof is bonded to L via a single bond, the nitrogen atom bonded to L via a single bond corresponds to the linking group in condition (b), and the two aryl groups correspond to the aromatic rings in condition (b). When the two aryl groups in the diarylamine structure are not bonded to each other and one of the aryl groups is bonded to L via a divalent linking group, the divalent linking group corresponds to the linking group in condition (b), and one of the aryl groups bonded to the divalent linking group corresponds to the aromatic ring in condition (b). When the two aryl groups in the diarylamine structure are not bonded to each other and the nitrogen atom thereof is linked to L via a divalent linking group, the divalent linking group and the nitrogen atom correspond to the linking group in condition (b), and the two aryl groups correspond to the aromatic ring in condition (b).

[0027] The two Ds (“one D” and “the other D”) that satisfy the condition (a) are preferably groups represented by the following general formula (2).

[0028] [ka]

[0029] In general formula (2), R 11 ~R 19 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 11 ~R 19 One of them is the bonding position with L. The one that is the bonding position with L is R 19 The number of substituents is not particularly limited, and R 11 ~R 19 All of R except for the bonding position with L may be unsubstituted (hydrogen atom). 11 ~R 19 When two or more of them are substituents, the substituents may be the same or different from each other, provided that between a group represented by general formula (2) which is one of D and a group represented by general formula (2) which is the other of D, R 11 ~R 19 are different from each other in at least one of the following conditions: the number of substituents, the position of the substituents, and the structure of the substituents. For example, in one D, R 11 ~R 18 At least one of D is a substituent, and the other D is R 11 ~R 18 Among these, it is preferable that the one corresponding to the substituent in one D is a hydrogen atom, and in one D, R 13 and R 16 At least one of D is a substituent, and the other D is R 13 and R 16 It is more preferable that the substituent in one of Ds is a hydrogen atom. 13 and R 16 It is more preferred that both of R 13 and R 16 It is even more preferred that both of R and R are substituted or unsubstituted aryl groups. 11 ~R 18 It is more preferable that all of are hydrogen atoms. Specific examples of the group represented by general formula (2) are given below. However, the group represented by general formula (2) that can be used in the present invention should not be construed as being limited by these specific examples. In the groups exemplified below, a single line extending from a benzene ring and not shown as a linking group to other atoms represents a methyl group. In the groups exemplified below, L replaces a hydrogen atom bonded to positions 1 to 9 of the carbazole ring and bonds to L. The bonding position of L on the carbazole ring is preferably position 9. As a combination of two Ds that satisfies condition (a), for example, a combination of two types of groups selected from these groups can be used.

[0030] [ka] JPEG0007758385000020.jpg98170JPEG0007758385000021.jpg157170

[0031] It is also preferable that the two Ds (“one D” and “the other D”) that satisfy the condition (a) or (b) are groups represented by any of the following general formulae (3) to (5).

[0032] [ka]

[0033] In the general formulas (3) to (5), R 21 ~R 31 , R 41 ~R 53 , R 61 ~R 73 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 21 ~R 31 One of the R 41 ~R 53 One of the R 61 ~R 73 One of them is a bonding position with L. The one that is a bonding position with L is R 31 , R 53 , R73 It is preferable that R 21 ~R 30 One of the R 41 ~R 52 One of the R 61 ~R 72 When one of R is the bonding position to L, the group represented by any of general formulas (3) to (5) is subject to condition (a). 31 , R 53 , R 73 is the bonding position with L, the group represented by any of the general formulae (3) to (5) is subject to the condition (b), the nitrogen atom corresponds to the linking group of the condition (b), and the benzene ring or naphthalene ring bonded to the nitrogen atom corresponds to the aromatic ring of the condition (b). The number of substituents in the general formulae (3) to (5) is not particularly limited, and R 21 ~R 31 , R 41 ~R 53 , R 61 ~R67, R68~R 72 All of the substituents except for the bonding position with L may be unsubstituted (hydrogen atoms). When there are two or more substituents in each of the general formulae (3) to (5), the substituents may be the same or different. However, between a group represented by any one of the general formulae (3) to (5) which is one D and a group represented by any one of the general formulae (3) to (5) which is the other D, R may be substituted so as to satisfy condition (a) or condition (b). 21 ~R 31 , R 41 ~R 53 and R 61 ~R 73 In at least one of the groups, at least one of the conditions of the number of substituents, the position of the substituents, and the structure of the substituents is different from each other. Specific examples of groups represented by any of general formulae (3) to (5) are given below. However, the groups represented by any of general formulae (3) to (5) that can be used in the present invention should not be construed as being limited by these specific examples. In the groups exemplified below, a single line extending from a benzene ring and not shown as a linking group to other atoms represents a methyl group. In the groups exemplified below, L is bonded to L by replacing the hydrogen atom of any one of the methine groups (-CH=) constituting the ring structure or the hydrogen atom bonded to the nitrogen atom. In these groups, the bonding position of L is preferably the nitrogen atom. As a combination of two Ds that satisfies condition (a) or (b), for example, a combination of two types of groups selected from these groups can be used.

[0034] [ka] JPEG0007758385000024.jpg186170JPEG0007758385000025.jpg213170JPEG0007758385000026.jpg66170

[0035] It is also preferable that the two Ds (“one D” and “the other D”) that satisfy the condition (a) or (b) are groups represented by the following general formula (6).

[0036] [ka] In general formula (6), R 81 ~R 95 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 81 ~R 95 One of them is the bonding position with L. The other one is the bonding position with L. 83In the group represented by general formula (6), of the three benzene rings bonded to the nitrogen atom, the benzene ring having the bonding position with L corresponds to the aromatic ring in condition (a). Alternatively, the benzene ring having the bonding position with L and the nitrogen atom can be considered to correspond to the linking group in condition (b), and the remaining two benzene rings can be considered to correspond to the aromatic rings in condition (b). The number of substituents is not particularly limited, and R 81 ~R 95 All of the groups except for the bonding position with L may be unsubstituted (hydrogen atoms). 81 ~R 95 When two or more of the groups represented by general formula (6) are substituents, the substituents may be the same or different from each other. However, between a group represented by general formula (6) which is one of D and a group represented by general formula (6) which is the other of D, R must be such that condition (a) or (b) is satisfied. 81 ~R 83 , R 86 ~R 90 and R 91 ~R 95 In at least one of the groups, at least one of the conditions of the number of substituents, the position of the substituents, and the structure of the substituents is different from each other.

[0037] It is also preferable that the two Ds (“one D” and “the other D”) that satisfy the condition (a) are groups represented by the following general formula (7).

[0038] [ka]

[0039] In general formula (7), R 101 ~R 109 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 101 ~R 109 One of them is the bonding position with L. The one that is the bonding position with L is R 109 The number of substituents is not particularly limited, and R 101 ~R 109 All of R except for the bonding position with L may be unsubstituted (hydrogen atom).101 ~R 109 When two or more of the groups represented by general formula (7) are substituents, the substituents may be the same or different from each other. However, between a group represented by general formula (7) which is one of D and a group represented by general formula (7) which is the other of D, R must be such that condition (a) is satisfied. 101 ~R 109 are different from each other in at least one of the following conditions: the number of substituents, the position of the substituents, and the structure of the substituents.

[0040] It is also preferable that the two Ds (“one D” and “the other D”) that satisfy the condition (a) are groups represented by the following general formula (8).

[0041] [ka]

[0042] In general formula (8), R 111 ~R 119 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 111 ~R 119 One of them is the bonding position with L. The one that is the bonding position with L is R 119 The number of substituents is not particularly limited, and R 111 ~R 119 All of the groups except for the bonding position with L may be unsubstituted (hydrogen atoms). 111 ~R 119 When two or more of the groups represented by general formula (8) are substituents, the substituents may be the same or different from each other. However, between a group represented by general formula (8) which is one of D and a group represented by general formula (8) which is the other of D, R must be such that condition (a) is satisfied. 111 ~R 119 are different from each other in at least one of the following conditions: the number of substituents, the position of the substituents, and the structure of the substituents.

[0043] It is also preferable that the two Ds (“one D” and “the other D”) that satisfy the condition (a) are groups represented by the following general formula (9).

[0044] [ka]

[0045] In general formula (9), R 121 ~R 131 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 121 ~R 131 One of them is the bonding position with L. The one that is the bonding position with L is R 131 The number of substituents is not particularly limited, and R 121 ~R 131 All of R except for the bonding position with L may be unsubstituted (hydrogen atom). 121 ~R 131 When two or more of the groups represented by general formula (9) are substituents, the substituents may be the same or different from each other. However, between a group represented by general formula (9) as one of D and a group represented by general formula (9) as the other of D, R 121 ~R 131 are different from each other in at least one of the following conditions: the number of substituents, the position of the substituents, and the structure of the substituents.

[0046] R in general formula (2) 11 ~R 19 and R in general formula (3) 21 ~R 31 and R in general formula (4) 41 ~R 53 and R in general formula (5) 61 ~R 73 and R in general formula (6) 81 ~R 95 and R in general formula (7) 101 ~R 109 and R in general formula (8) 111 ~R 119 and R in general formula (9) 121 ~R 131Examples of the substituent that may be taken by the group include a hydroxy group, a halogen atom, a cyano group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkyl-substituted amino group having 1 to 20 carbon atoms, an acyl group having 2 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, a heteroaryl group having 3 to 40 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an alkoxycarbonyl group having 2 to 10 carbon atoms, an alkylsulfonyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an amido group, an alkylamido group having 2 to 10 carbon atoms, a trialkylsilyl group having 3 to 20 carbon atoms, a trialkylsilylalkyl group having 4 to 20 carbon atoms, a trialkylsilylalkenyl group having 5 to 20 carbon atoms, a trialkylsilylalkynyl group having 5 to 20 carbon atoms, and a nitro group. Among these specific examples, those which can be further substituted with a substituent may be substituted with, for example, the substituents of these specific examples. More preferred substituents are a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, a substituted or unsubstituted diarylamino group having 1 to 20 carbon atoms, and a substituted or unsubstituted carbazolyl group.

[0047] The remaining groups in D, excluding those satisfying condition (a) or (b), may be groups with negative Hammett σp values, and are not otherwise particularly limited. However, they preferably contain a diarylamine structure (provided that the two aryl groups constituting the diarylamine structure may be bonded to each other), more preferably contain a diarylamino group (provided that the two aryl groups constituting the diarylamino group may be bonded to each other), and even more preferably are groups represented by general formulas (2) to (9). For descriptions, preferred ranges, and specific examples of these structures and groups, please refer to the descriptions, preferred ranges, and specific examples of the diarylamine structure, diarylamino group, and groups represented by general formulas (2) to (9) for the two Ds satisfying condition (a) or (b). However, in these references, any description of condition (a) or (b) is not included in the reference content.

[0048] The compound represented by general formula (1) is preferably a compound represented by the following general formula (10).

[0049] [ka]

[0050] In general formula (10), A 1 represents a group with a positive Hammett σp value. 1 ~R 5 each independently represents a hydrogen atom, a group having a positive Hammett σp value, or a group having a negative Hammett σp value; R 1 ~R 5 At least two of the R groups have a negative Hammett σp value (except for the phenyl group). 1 ~R 6 When one or more of the Hammett σp values ​​are positive, A 1 The Hammett σp value is positive and R 1 ~R 6 Among these, the groups having a positive Hammett σp value may be the same or different. R 1 ~R 5 Of these, two groups having negative Hammett σp values ​​preferably satisfy the following condition (a) or (b): Condition (a) Both of the two groups having negative Hammett σp values ​​have an aromatic ring containing an atom bonded to L, and the aromatic ring is common between the two groups having negative Hammett σp values, but at least one of the conditions of the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring is different. Condition (b) When two groups with negative Hammett σp values ​​both have a linking group bonded to L and one or more aromatic rings bonded to the linking group, and both of the two groups with negative Hammett σp values ​​have one aromatic ring bonded to the linking group, the two groups with negative Hammett σp values ​​have the same linking group and aromatic ring bonded to the linking group, but are different from each other in at least one condition: the number of substituents substituted on the aromatic ring, the position of the substitution by the substituent on the aromatic ring, and the structure of the substituent substituted on the aromatic ring. When two groups with negative Hammett σp values ​​both have two or more aromatic rings bonded to a linking group, the two groups with negative Hammett σp values ​​have common linking groups, common numbers of aromatic rings bonded to the linking groups, and common aromatic rings, but at least one of the combinations of common aromatic rings between the two groups with negative Hammett σp values ​​differs from each other in at least one of the conditions: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. A 1 , R 1 ~R 5 The Hammett σp value is positive, R 1 ~R 5 The Hammett σp value is negative, and R 1 ~R 5 For the explanation of two of the groups having a negative Hammett σp value, the preferred ranges, specific examples, and conditions (a) and (b), reference can be made to the explanation of the group having a positive Hammett σp value represented by A in general formula (1), the group having a negative Hammett σp value represented by D, and the explanation of two of the multiple Ds, the preferred ranges, specific examples, and conditions (a) and (b), respectively.

[0051] R 1 ~R 5 The number of groups having a positive Hammett σp value among R is preferably 0 to 3, more preferably 0 to 2, further preferably 0 or 1, and most preferably 0. 1 ~R 5Among R, the number of groups having a negative Hammett σp value is preferably 2 to 5, more preferably 3 to 5, even more preferably 4 or 5, and most preferably 5. 1 ~R 5 Among these, the combination of two groups satisfying condition (a) or condition (b) may be one or two. In addition, the combination of two groups satisfying condition (a) or condition (b) is preferably a combination of groups that are positioned point-symmetrically to each other on the benzene ring in general formula (1). That is, R 1 and R 4 Combination of, and,R 2 and R 5 It is preferred that one or both of the above combinations satisfy condition (a) or condition (b).

[0052] The compound represented by general formula (1) is also preferably a compound represented by the following general formula (11). [ka]

[0053] In general formula (11), A X1 represents a group with a positive Hammett σp value. X11 ~R X14 each independently represents a hydrogen atom, a group having a positive Hammett σp value, or a group having a negative Hammett σp value; R X11 ~R X14 At least two of the R groups have a negative Hammett σp value (except for the phenyl group). X11 ~R X14 When one or more of the Hammett σp values ​​are positive, A X1 The Hammett σp value is positive and R X11 ~R X14 Among these, the groups having a positive Hammett σp value may be the same or different. R X11 ~R X14 Of these, two groups having negative Hammett σp values ​​preferably satisfy the above condition (a) or condition (b). A1 , R X11 ~R X14 The Hammett σp value is positive, R X11 ~R X14 The Hammett σp value is negative, and R X11 ~R X14 For the explanation of two of the groups having a negative Hammett σp value, the preferred ranges, specific examples, and conditions (a) and (b), reference can be made to the explanation of the group having a positive Hammett σp value represented by A in general formula (1), the group having a negative Hammett σp value represented by D, and the explanation of two of the multiple Ds, the preferred ranges, specific examples, and conditions (a) and (b), respectively.

[0054] R X11 ~R X14 The number of groups having a positive Hammett σp value among R is preferably 0 to 2, more preferably 0 or 1, and most preferably 0. X11 ~R X14 Among R, the number of groups having a negative Hammett σp value is preferably 2 to 4, more preferably 3 or 4, and even more preferably 4. X11 ~R X14 Among these, the combination of two groups satisfying condition (a) or condition (b) may be one or two.

[0055] Specific examples of compounds represented by general formula (1) are given below. Among the specific examples, compounds 1 to 7 are identified in the table, and their structural formulas are also shown below. Compounds 8 and onward are identified only in the table. However, the compounds represented by general formula (1) that can be used in the present invention should not be construed as being limited by these specific examples. [ka]

[0056] The following table lists specific examples of compounds represented by general formula (10) or general formula (11). General formulas (2a) and (2b) representing substituents in general formula (10) and general formula (11) are also listed below. [ka]

[0057] [Table 1] JPEG0007758385000036.jpg223122JPEG0007758385000037.jpg223126JPEG0007758385000038.jpg223110

[0058] [Table 2] JPEG0007758385000040.jpg110170

[0059] [Table 3]

[0060] [Table 4] JPEG0007758385000043.jpg232115

[0061] [Table 5] JPEG0007758385000045.jpg215170JPEG0007758385000046.jpg216112

[0062] [Table 6] JPEG0007758385000048.jpg21682

[0063] [Table 7]

[0064] [Table 8]

[0065] The structures of D1 to D60 and A1 to A13 in Tables 1 to 8 are shown below. [ka]

[0066] [ka]

[0067] [ka]

[0068] [ka]

[0069] [ka]

[0070] When it is intended to use an organic layer containing the compound represented by general formula (1) formed by vapor deposition, the molecular weight of the compound represented by general formula (1) is preferably 1500 or less, more preferably 1200 or less, even more preferably 1000 or less, and even more preferably 800 or less. The lower limit of the molecular weight is the molecular weight of the smallest compound represented by general formula (1). The compound represented by general formula (1) may be formed into a film by a coating method regardless of its molecular weight. If a coating method is used, it is possible to form a film even from a compound with a relatively large molecular weight.

[0071] It is also conceivable that the present invention can be applied to use a compound containing a plurality of structures represented by general formula (1) in the molecule as a light-emitting material. For example, a polymerizable group may be pre-existed in the structure represented by general formula (1), and the polymer obtained by polymerizing the polymerizable group may be used as a light-emitting material. Specifically, a monomer containing a polymerizable functional group in any of L, A, and D in general formula (1) may be prepared, and this may be polymerized alone or copolymerized with other monomers to obtain a polymer having repeating units, and the polymer may be used as a light-emitting material. Alternatively, compounds having a structure represented by general formula (1) may be coupled to obtain dimers or trimers, which may be used as light-emitting materials.

[0072] Examples of polymers having a repeating unit containing a structure represented by general formula (1) include polymers containing a structure represented by the following general formula (12) or (13). [ka]

[0073] In the general formula (12) or (13), Q represents a group containing the structure represented by the general formula (1), and L 1 and L 2 represents a linking group. The number of carbon atoms in the linking group is preferably 0 to 20, more preferably 1 to 15, and even more preferably 2 to 10. The linking group is -X 11 -L 11 Preferably, X has a structure represented by the formula: 11 represents an oxygen atom or a sulfur atom, and is preferably an oxygen atom. 11 represents a linking group, which is preferably a substituted or unsubstituted alkylene group or a substituted or unsubstituted arylene group, and more preferably a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms or a substituted or unsubstituted phenylene group. In the general formula (12) or (13), R201 , R 202 , R 203 and R 204 each independently represents a substituent, preferably a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a halogen atom, more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms, an unsubstituted alkoxy group having 1 to 3 carbon atoms, a fluorine atom, or a chlorine atom, and still more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms, or an unsubstituted alkoxy group having 1 to 3 carbon atoms. L 1 and L 2 The linking group represented by the following formula can be bonded to any of L, A, and D in the structure of general formula (1) constituting Q. Two or more linking groups may be linked to one Q to form a crosslinked structure or a network structure.

[0074] Specific structural examples of the repeating unit include structures represented by the following general formulas (14) to (17). [ka]

[0075] The polymer having repeating units containing these general formulas (14) to (17) can be synthesized by introducing a hydroxy group into any one of L, A, and D in the structure of general formula (1), reacting the hydroxy group as a linker with the following compound to introduce a polymerizable group, and polymerizing the polymerizable group. [ka]

[0076] A polymer containing a structure represented by general formula (1) in its molecule may be a polymer consisting only of repeating units having the structure represented by general formula (1), or may be a polymer containing repeating units having other structures. The repeating units having the structure represented by general formula (1) contained in the polymer may be of a single type, or may be of two or more types. Examples of repeating units not having the structure represented by general formula (1) include those derived from monomers used in ordinary copolymerization. For example, repeating units derived from monomers having an ethylenically unsaturated bond, such as ethylene and styrene, can be mentioned.

[0077] [Method for synthesizing the compound represented by general formula (1)] The compound represented by general formula (1) can be synthesized by combining known reactions. For example, it can be synthesized by further introducing D into an aromatic compound into which A has already been introduced. The introduction of D can be carried out, for example, by an aromatic nucleophilic substitution reaction. A generalized scheme of such a reaction is shown below as an example. [ka]

[0078] The definitions of A, L, m, and n in general formulas (18) to (20) are the same as those in general formula (1). X in general formulas (18) and (19) represents a halogen atom. Examples of halogen atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom, a chlorine atom, and a bromine atom are preferred, a fluorine atom and a chlorine atom are more preferred, and a fluorine atom is even more preferred. In general formulas (19), (20), and HD 1 D in 1 and general formula (20) and HD 2 D in 2 are each independently a group with a negative Hammett σp value (excluding phenyl groups). 1 and D 2The structures of are different from each other. p is an integer of 1 or more and less than n. When multiple As exist in a molecule, the multiple As may be the same or different. When multiple Xs exist in a molecule, the multiple Xs may be the same or different. In the above (Scheme 1), a halogen-substituted aromatic compound in which A has already been introduced is used as a starting material. 1 By reacting at least one halogen atom bonded to the aromatic ring with D 1 This allows the compound represented by general formula (19) to be obtained. By controlling the reaction conditions, changing the purification conditions, or 1 X and D of the position where you want to introduce 2 By changing the halogen species of X at the position where you want to introduce, the value of p in the obtained general formula (19) and D in the aromatic ring 1 Next, the compound of general formula (19) is introduced with HD 2 By reacting with the remaining halogen atoms bonded to the aromatic ring, 2 This allows the compound represented by general formula (20) to be obtained. The compound represented by general formula (20) is the compound represented by general formula (1).

[0079] (Scheme 1) is HD 1 After reacting with HD 2 The compound represented by general formula (1) is synthesized by a two-step reaction of 1 After reacting with HD 2 reacts and HD 3 It is also possible to synthesize the compound represented by general formula (1) in a three-step reaction in which D 3 is D 1 and D 2 It is a group with a negative Hammett σp value and a structure different from that of the . According to this three-step reaction, D 1 , D 2 , D 3It is possible to obtain a compound of general formula (1) having three types of D. Furthermore, by further applying this concept and carrying out a multi-step reaction, it is possible to obtain a compound of general formula (1) having three types of D. 1 , D 2 , D 3 ···D w It is also possible to obtain a compound of general formula (1) having w kinds of D.

[0080] (Scheme 1) is HD 1 After reacting with HD 2 As shown in the following (Scheme 2), the starting material, general formula (18), is reacted with HD 1 and HD 2 In this case, the reaction conditions, HD 1 and HD 2 By controlling the ratio of the halogen atoms present, the type of halogen atom, and purification conditions, a compound with the desired p can be obtained. 1 , HD 2 HD w In the presence of D in the reaction mixture 1 , D 2 , D 3 ···D w It is also possible to obtain a compound of general formula (1) having w kinds of D. [ka]

[0081] The target compounds in (Scheme 1) and (Scheme 2) can be synthesized by applying the following aromatic nucleophilic substitution reaction. They can also be synthesized according to the method described in S. Tanimoto, et al., Chem. Lett., 45, 770 (2016). For specific reaction conditions and synthesis procedures, please refer to the synthesis examples described below. [ka]

[0082] (Synthetic intermediate) The compound represented by the general formula (19) is useful as a synthetic intermediate for the compound represented by the general formula (20) [the compound represented by the general formula (1)]. For the explanation and preferred ranges of A, L, m, and n in general formula (19), the explanation and preferred ranges of A, L, m, and n in general formula (1) can be referred to. p in general formula (19) is an integer of 1 or more and less than n, preferably in the range of 1 to 3, and more preferably 1 or 2. D in general formula (19) 1 Regarding X, the description of D in general formula (1) and the preferred range can be referred to, but it is preferably a group containing a heteroatom, and more preferably a group in which an aromatic ring is bonded to a heteroatom. It is preferable to use a nitrogen atom as the heteroatom. Preferred examples include groups containing a diarylamine structure and a carbazolyl structure. A can preferably be a cyano group. Furthermore, when p is 2 or more and L is a 6-membered aromatic ring linking group, it is preferable that at least two Xs are bonded to each other so as to be located at the para-position of the 6-membered aromatic ring.

[0083] Specific examples of compounds of general formula (19) include compounds in which the group represented by general formula (2b) in the table of specific compound examples of general formula (1) is substituted with a halogen atom. That is, compounds in which the group represented by general formula (2b) in compound numbers 1 to 912 listed as specific compound examples of general formula (1) is substituted with a fluorine atom are specifically disclosed herein as compound numbers 1001 to 1912. Furthermore, compounds in which the group represented by general formula (2b) in compound numbers 1 to 912 listed as specific compound examples of general formula (1) is substituted with a chlorine atom are specifically disclosed herein as compound numbers 2001 to 2912. Furthermore, compounds in which the group represented by general formula (2b) in compound numbers 1 to 912 listed as specific compound examples of general formula (1) is substituted with a bromine atom are specifically disclosed herein as compound numbers 3001 to 3912. Furthermore, compounds in which the group represented by general formula (2b) in compound numbers 1 to 912 given as specific examples of compounds of general formula (1) is substituted with an iodine atom are specifically disclosed in this specification as compound numbers 4001 to 4912. Note that, among compound numbers 1001 to 4912, those in which general formula (2b) does not exist in the corresponding compound numbers 1 to 912 are omitted.

[0084] [Organic light-emitting element] The compound represented by general formula (1) of the present invention is useful as a material for light-emitting devices, and can be particularly suitably used as a light-emitting material for organic light-emitting devices. Therefore, the compound represented by general formula (1) of the present invention can be effectively used as a light-emitting material in the light-emitting layer of an organic light-emitting device. Among the compounds represented by general formula (1) are delayed fluorescent materials (delayed fluorescent materials) that emit delayed fluorescence. That is, the present invention also provides a delayed fluorescent material having a structure represented by general formula (1), a method for using a compound represented by general formula (1) as a delayed fluorescent material, and a method for emitting delayed fluorescence using a compound represented by general formula (1). Organic light-emitting devices using such compounds as light-emitting materials are characterized by emitting delayed fluorescence and having high luminous efficiency. The principle behind this is explained below using an organic electroluminescence device as an example.

[0085] In organic electroluminescent devices, carriers are injected into the light-emitting material from both the positive and negative electrodes to generate an excited light-emitting material, which then emits light. Typically, in carrier-injection organic electroluminescent devices, only 25% of the generated excitons are excited to the singlet state, while the remaining 75% are excited to the triplet state. Therefore, utilizing phosphorescence, which is light emitted from the triplet state, offers higher energy utilization efficiency. However, because the triplet state has a long lifetime, energy deactivation occurs due to saturation of the excited state or interaction with the triplet excitons, and the quantum yield of phosphorescence is generally low. On the other hand, delayed fluorescent materials undergo energy transition to the excited triplet state via intersystem crossing, etc., and then undergo reverse intersystem crossing to the excited singlet state via triplet-triplet annihilation or the absorption of thermal energy, resulting in the emission of fluorescence. Thermally activated delayed fluorescent materials, which absorb thermal energy, are considered particularly useful in organic electroluminescent devices. When a delayed fluorescent material is used in an organic electroluminescent device, excitons in the excited singlet state emit fluorescence as usual. Meanwhile, excitons in the excited triplet state absorb heat generated by the device and undergo intersystem crossing to the excited singlet state, emitting fluorescence. While the emission from the excited singlet state has the same wavelength as fluorescence, the reverse intersystem crossing from the excited triplet state to the excited singlet state results in a longer lifetime (emission lifetime) than that of normal fluorescence or phosphorescence, resulting in the observed fluorescence being delayed. This can be defined as delayed fluorescence. By using this thermally activated exciton transfer mechanism, the proportion of the compound in the excited singlet state, which is normally only 25%, can be increased to over 25% by absorbing thermal energy after carrier injection. By using a compound that emits strong fluorescence and delayed fluorescence even at temperatures below 100°C, the heat from the device is sufficient to cause intersystem crossing from the excited triplet state to the excited singlet state, resulting in delayed fluorescence emission, dramatically improving luminous efficiency.

[0086] In particular, the compound represented by the general formula (1) that emits delayed fluorescence has a rate constant k RISCSince the valence energy of the compound represented by general formula (1) is very large, it is presumed that the accumulation of triplet excitons during the excitation process is effectively suppressed. As a result, in light-emitting devices using the compound represented by general formula (1), exciton annihilation and device degradation due to the accumulation of triplet excitons are suppressed, resulting in higher luminous efficiency and excellent durability. Furthermore, the suppression of exciton annihilation can greatly contribute to the realization of organic lasers.

[0087] By using the compound represented by general formula (1) of the present invention as a light-emitting material in the light-emitting layer, it is possible to provide excellent organic light-emitting devices such as organic photoluminescence devices (organic PL devices) and organic electroluminescence devices (organic EL devices). In this case, the compound represented by general formula (1) of the present invention may have a function of assisting the emission of other light-emitting materials contained in the light-emitting layer as a so-called assist dopant. In other words, the compound represented by general formula (1) of the present invention contained in the light-emitting layer may have a lowest excited singlet energy level between the lowest excited singlet energy level of the host material contained in the light-emitting layer and the lowest excited singlet energy level of the other light-emitting materials contained in the light-emitting layer. An organic photoluminescent device has a structure in which at least an emitting layer is formed on a substrate. An organic electroluminescent device has a structure in which at least an anode, a cathode, and an organic layer are formed between the anode and the cathode. The organic layer includes at least an emitting layer, and may consist of only the emitting layer, or may have one or more organic layers in addition to the emitting layer. Examples of such other organic layers include a hole transport layer, a hole injection layer, an electron blocking layer, a hole blocking layer, an electron injection layer, an electron transport layer, and an exciton blocking layer. The hole transport layer may be a hole injection transport layer with hole injection function, and the electron transport layer may be an electron injection transport layer with electron injection function. A specific example of the structure of an organic electroluminescent device is shown in Figure 1. In Figure 1, 1 represents the substrate, 2 represents the anode, 3 represents the hole injection layer, 4 represents the hole transport layer, 5 represents the emitting layer, 6 represents the electron transport layer, and 7 represents the cathode. Each component and each layer of the organic electroluminescent element will be described below. The description of the substrate and the light-emitting layer also applies to the substrate and the light-emitting layer of the organic photoluminescent element.

[0088] (substrate) The organic electroluminescent device of the present invention is preferably supported on a substrate. There are no particular limitations on the substrate, and it may be made of a material that has been conventionally used for organic electroluminescent devices, such as glass, transparent plastic, quartz, or silicon.

[0089] (anode) Anodes in organic electroluminescent devices are preferably made of metals, alloys, electrically conductive compounds, or mixtures thereof with a high work function (4 eV or higher). Specific examples of such electrode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO2, and ZnO. Amorphous materials capable of forming transparent conductive films, such as IDIXO (In2O3-ZnO), may also be used. The anode may be formed by depositing a thin film of these electrode materials using methods such as vapor deposition or sputtering, followed by photolithography to form a desired pattern. Alternatively, if pattern precision is not required (approximately 100 μm or higher), a pattern may be formed using a mask of the desired shape during vapor deposition or sputtering of the electrode material. Alternatively, when a coatable material, such as an organic conductive compound, is used, wet film formation methods such as printing or coating can also be used. When light is emitted from this anode, a transmittance of more than 10% is desirable, and the sheet resistance of the anode is preferably less than several hundred Ω / □. Furthermore, the film thickness depends on the material, but is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

[0090] (cathode) On the other hand, the cathode is typically made of a metal (referred to as an electron-injecting metal), alloy, electrically conductive compound, or mixture thereof with a low work function (4 eV or less). Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, a magnesium / copper mixture, a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al2O3) mixture, indium, a lithium / aluminum mixture, and rare earth metals. Among these, mixtures of an electron-injecting metal and a second metal with a higher and more stable work function, such as a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al2O3) mixture, a lithium / aluminum mixture, and aluminum, are preferred in terms of electron injection properties and durability against oxidation. The cathode can be fabricated by forming a thin film of these electrode materials by methods such as vapor deposition or sputtering. The sheet resistance of the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. In order to transmit emitted light, it is advantageous to improve the luminance of emitted light if either the anode or cathode of the organic electroluminescence element is transparent or semitransparent. Furthermore, by using the conductive transparent materials mentioned in the explanation of the anode for the cathode, a transparent or semitransparent cathode can be fabricated. This can be applied to fabricate an element in which both the anode and cathode are transparent.

[0091] (light-emitting layer) The emissive layer emits light after excitons are generated by the recombination of holes and electrons injected from the anode and cathode, respectively. While the emissive layer may contain a single emissive material, it preferably contains both an emissive material and a host material. The emissive material may be one or more compounds selected from the group of compounds of the present invention represented by general formula (1). For the organic electroluminescent device and organic photoluminescent device of the present invention to exhibit high luminous efficiency, it is important to confine the singlet and triplet excitons generated in the emissive material within the emissive material. Therefore, it is preferable to use a host material in addition to the emissive material in the emissive layer. The host material may be an organic compound having at least one of the excited singlet energy and the excited triplet energy higher than that of the emissive material of the present invention. As a result, the singlet and triplet excitons generated in the emissive material of the present invention can be confined within the molecules of the emissive material, thereby fully utilizing its luminous efficiency. However, since high luminous efficiency may be obtained even if singlet excitons and triplet excitons cannot be sufficiently confined, any host material capable of achieving high luminous efficiency can be used in the present invention without particular restrictions. In the organic light-emitting device or organic electroluminescent device of the present invention, light emission occurs from the light-emitting material of the present invention contained in the light-emitting layer. This light emission includes both fluorescent light emission and delayed fluorescent light emission. However, it is acceptable if part or a portion of the light emission comes from the host material. When a host material is used, the amount of the compound of the present invention, which is the light-emitting material, contained in the light-emitting layer is preferably 0.1% by weight or more, more preferably 1% by weight or more, and is preferably 50% by weight or less, more preferably 20% by weight or less, and even more preferably 10% by weight or less. The host material in the light-emitting layer is preferably an organic compound that has hole transporting ability and electron transporting ability, prevents the wavelength of emitted light from shifting to longer wavelengths, and has a high glass transition temperature.

[0092] (Injection layer) The injection layer is a layer provided between an electrode and an organic layer to reduce the driving voltage and improve the luminance of light emitted, and includes a hole injection layer and an electron injection layer, and may be provided between the anode and the light emitting layer or the hole transport layer, and between the cathode and the light emitting layer or the electron transport layer. The injection layer can be provided as needed.

[0093] (blocking layer) A blocking layer is a layer that can prevent the diffusion of charges (electrons or holes) and / or excitons present in the light-emitting layer out of the light-emitting layer. An electron blocking layer can be disposed between the light-emitting layer and the hole-transporting layer and prevents electrons from passing through the light-emitting layer toward the hole-transporting layer. Similarly, a hole-blocking layer can be disposed between the light-emitting layer and the electron-transporting layer and prevents holes from passing through the light-emitting layer toward the electron-transporting layer. A blocking layer can also be used to prevent excitons from diffusing out of the light-emitting layer. That is, an electron blocking layer and a hole-blocking layer can each also function as an exciton-blocking layer. In this specification, the terms "electron blocking layer" and "exciton blocking layer" are used to mean a layer that functions as both an electron blocking layer and an exciton-blocking layer.

[0094] (Hole blocking layer) In a broad sense, the hole-blocking layer functions as an electron-transporting layer. The hole-blocking layer transports electrons while blocking holes from reaching the electron-transporting layer, thereby improving the probability of recombination of electrons and holes in the light-emitting layer. The materials for the electron-transporting layer, which will be described later, can be used as materials for the hole-blocking layer, if necessary.

[0095] (electron blocking layer) In a broad sense, an electron blocking layer has the function of transporting holes. The electron blocking layer transports holes while blocking electrons from reaching the hole transport layer, thereby increasing the probability of electron and hole recombination in the light-emitting layer.

[0096] (Exciton blocking layer) The exciton-blocking layer is a layer that prevents excitons generated by the recombination of holes and electrons in the light-emitting layer from diffusing into the charge-transport layer. Insertion of this layer allows for efficient confinement of excitons within the light-emitting layer, thereby improving the luminous efficiency of the device. The exciton-blocking layer can be inserted adjacent to the light-emitting layer on either the anode side or the cathode side, or both sides at the same time. That is, when the exciton-blocking layer is located on the anode side, it can be inserted between the hole-transport layer and the light-emitting layer, adjacent to the light-emitting layer. When it is located on the cathode side, it can be inserted between the light-emitting layer and the cathode, adjacent to the light-emitting layer. Furthermore, a hole-injection layer or an electron-blocking layer can be located between the anode and the exciton-blocking layer adjacent to the anode side of the light-emitting layer, and an electron-injection layer, an electron-transport layer, a hole-blocking layer, or the like can be located between the cathode and the exciton-blocking layer adjacent to the cathode side of the light-emitting layer. When a blocking layer is provided, it is preferable that at least one of the excited singlet energy and excited triplet energy of the material used as the blocking layer is higher than the excited singlet energy and excited triplet energy of the light-emitting material.

[0097] (Hole transport layer) The hole transport layer is made of a hole transport material having a function of transporting holes, and the hole transport layer may be provided as a single layer or as a plurality of layers. The hole transport material has either hole injection or transport or electron barrier properties, and may be either organic or inorganic. Examples of known hole transport materials that can be used include triazole derivatives, oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers. Among these, porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds are preferred, and aromatic tertiary amine compounds are more preferred.

[0098] (electron transport layer) The electron transport layer is made of a material having the function of transporting electrons, and the electron transport layer may be a single layer or a plurality of layers. The electron transport material (which may also serve as a hole blocking material) may have the function of transporting electrons injected from the cathode to the light-emitting layer. Usable electron transport materials include, for example, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, and oxadiazole derivatives. Furthermore, among the above oxadiazole derivatives, thiadiazole derivatives in which the oxygen atom of the oxadiazole ring is replaced with a sulfur atom, and quinoxaline derivatives having a quinoxaline ring known as an electron-withdrawing group can also be used as electron transport materials. Furthermore, polymeric materials in which these materials are incorporated into a polymer chain or in which these materials form the main chain of a polymer can also be used.

[0099] When fabricating an organic electroluminescence device, the compound represented by general formula (1) may be used not only in the light-emitting layer but also in layers other than the light-emitting layer. In this case, the compound represented by general formula (1) used in the light-emitting layer and the compound represented by general formula (1) used in the layers other than the light-emitting layer may be the same or different. For example, the compound represented by general formula (1) may also be used in the injection layer, blocking layer, hole-blocking layer, electron-blocking layer, exciton-blocking layer, hole-transporting layer, electron-transporting layer, etc. The film formation method for these layers is not particularly limited, and they may be fabricated by either a dry process or a wet process.

[0100] Specific examples of preferred materials that can be used in organic electroluminescence devices are given below. However, the materials that can be used in the present invention are not limited to the following exemplary compounds. Furthermore, even compounds exemplified as materials having specific functions can be diverted to materials having other functions.

[0101] First, preferred compounds that can also be used as the host material for the light-emitting layer will be listed.

[0102] [ka]

[0103] [ka] JPEG0007758385000064.jpg122166

[0104] [ka]

[0105] [ka]

[0106] [ka]

[0107] Next, examples of preferred compounds that can be used as the hole injection material will be given.

[0108] [ka]

[0109] Next, examples of preferred compounds that can be used as the hole transport material will be given.

[0110] [ka]

[0111] [ka] JPEG0007758385000071.jpg98170

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] Next, preferred examples of compounds that can be used as electron blocking materials are listed.

[0117] [ka]

[0118] Next, examples of preferred compounds that can be used as hole blocking materials are listed below.

[0119] [ka]

[0120] Next, examples of preferred compounds that can be used as the electron transport material will be given.

[0121] [ka]

[0122] [ka]

[0123] [ka]

[0124] Next, preferred examples of compounds that can be used as the electron injection material will be listed.

[0125] [ka]

[0126] Further, examples of compounds that can be added as materials are given below, which may be added as stabilizing materials, for example.

[0127] [ka]

[0128] The organic electroluminescent element produced by the above-mentioned method emits light when an electric field is applied between the anode and cathode of the resulting element. At this time, if the light is emitted by excited singlet energy, light of a wavelength corresponding to the energy level is confirmed as fluorescence and delayed fluorescence. Furthermore, if the light is emitted by excited triplet energy, light of a wavelength corresponding to the energy level is confirmed as phosphorescence. Since normal fluorescence has a shorter fluorescence lifetime than delayed fluorescence, the emission lifetime can be distinguished between fluorescence and delayed fluorescence. On the other hand, phosphorescence is hardly observable at room temperature in ordinary organic compounds such as the compound of the present invention because the excited triplet energy is unstable and is converted into heat, etc., has a short lifetime, and is immediately deactivated. The excited triplet energy of ordinary organic compounds can be measured by observing the luminescence under cryogenic conditions.

[0129] The organic electroluminescent device of the present invention can be applied as a single device, a device with a structure in which elements are arranged in an array, or a structure in which anodes and cathodes are arranged in an XY matrix. According to the present invention, by incorporating a compound represented by general formula (1) into the light-emitting layer, an organic light-emitting device with significantly improved luminous efficiency can be obtained. Organic light-emitting devices such as the organic electroluminescent device of the present invention can be further applied to a variety of uses. For example, an organic electroluminescent display device can be manufactured using the organic electroluminescent device of the present invention. For details, see "Organic EL Display" (Ohmsha), co-authored by Shizuo Tokito, Chinaya Adachi, and Hideyuki Murata. Furthermore, the organic electroluminescent device of the present invention can also be applied to organic electroluminescent lighting and backlighting, which are in high demand.

[0130] The present invention also includes the following: [1] A compound represented by the following general formula (1): [ka] [In general formula (1), L is an aromatic linking group having a valence of m+n, A is a group having a positive Hammett σp value, D is a group having a negative Hammett σp value, m is an integer of 1 or more, and n is an integer of 2 or more. When m is 2 or more, multiple As may be the same or different. Two of the multiple Ds satisfy the following condition (a) or the following condition (b). Condition (a) Both of the two Ds have an aromatic ring containing an atom bonded to L, and the aromatic ring is common between the two Ds, but at least one of the conditions of the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring is different. Condition (b) Both Ds have a linking group bonded to L and one aromatic ring bonded to the linking group, and the two Ds have the same linking group and aromatic ring bonded to the linking group, but are different from each other in at least one condition: the number of substituents substituted on the aromatic ring, the positions on the aromatic ring where the substituents are substituted, and the structure of the substituents substituted on the aromatic ring. Both Ds have a linking group bonded to L and two or more aromatic rings bonded to the linking group, and the two Ds have the same linking group, the number of aromatic rings bonded to the linking group, and the multiple aromatic rings, but are different from each other in at least one condition: the number of substituents substituted on the aromatic ring, the positions on the aromatic ring where the substituents are substituted, and the structure of the substituents substituted on the aromatic ring. [2] The compound according to [1], wherein two of the plurality of Ds comprise a diarylamine structure (provided that the two aryl groups constituting the diarylamine structure may be bonded to each other). [3] The compound according to [2], wherein the diarylamine structure is a carbazole structure. [4] The compound according to [1], wherein two of the plurality of Ds comprise a diarylamino group (wherein the two aryl groups constituting the diarylamino group may be bonded to each other). [5] The compound according to [4], wherein the diarylamino group is bonded to L via a single bond. [6] The compound according to any one of [1] to [5], wherein two of the plurality of Ds satisfy the condition (a). [7] The compound according to [1], wherein two of the plurality of Ds are groups represented by the following general formula (2): [ka] [In general formula (2), R 11 ~R 19 each independently represents a hydrogen atom, a substituent, or a bonding position with L, and R 11 ~R 19 One of these is the bonding position to L.] [8] R in the general formula (2) 19 is the bonding position to L. [9] One of two of the plurality of Ds is R in the general formula (2). 11 ~R 18 At least one of the Ds is a substituent, and the other two of the Ds are R 11 ~R 18 wherein one of the two D's that is a substituent corresponds to a hydrogen atom.

[10] One of two of the plurality of Ds is R in the general formula (2). 13 and R 16 The compound according to any one of [7] to [9], wherein at least one of the following is a substituent.

[11] The compound according to [9] or

[10] , wherein the substituent is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

[12] The compound according to [1], wherein the compound represented by the general formula (1) is a compound represented by the following general formula (10): [ka] [In the general formula (10), A 1 represents a group with a positive Hammett σp value. 1~R 5 each independently represents a hydrogen atom, a group having a positive Hammett σp value, or a group having a negative Hammett σp value; R 1 ~R 5 At least two of these groups have a negative Hammett σp value. 1 ~R 6 When one or more of the groups has a positive Hammett σp value, A 1 The Hammett σp value is positive and R 1 ~R 6 Among these, the groups having a positive Hammett σp value may be the same or different. 1 ~R 5 Among these, two groups having negative Hammett σp values ​​satisfy the following condition (a) or (b). Condition (a) The two groups having negative Hammett σp values ​​each have an aromatic ring containing an atom bonded to the benzene ring of general formula (10), and the two groups having negative Hammett σp values ​​have the same aromatic ring, but differ from each other in at least one of the following conditions: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. Condition (b) The two groups with negative Hammett σp values ​​each have a linking group bonded to the benzene ring of general formula (10) and one aromatic ring bonded to the linking group, and the two groups with negative Hammett σp values ​​have the linking group and the aromatic ring bonded to the linking group in common, but are different from each other in at least one condition: the number of substituents substituted on the aromatic ring, the positions of the substituents on the aromatic ring, and the structure of the substituents substituted on the aromatic ring. The two groups having a negative Hammett σp value each have a linking group bonded to a benzene ring of general formula (10) and two or more aromatic rings bonded to the linking group, and the linking group, the number of aromatic rings bonded to the linking group, and the number of aromatic rings are common between the two groups having a negative Hammett σp value, but in at least one combination of aromatic rings common between the two groups having a negative Hammett σp value, at least one of the conditions of the number of substituents substituted on the aromatic ring, the position of substitution by the substituent on the aromatic ring, and the structure of the substituent substituted on the aromatic ring is different from each other.

[13] R in the general formula (10) 1 ~R 5 is a group having a negative Hammett σp value.

[14] R in the general formula (10) 1 and R 4 Combination of, and,R 2 and R 5 The compound according to

[13] , wherein at least one of the combinations satisfies the condition (a) or (b).

[15] A light-emitting material comprising the compound according to any one of [1] to

[14] .

[16] A light-emitting device comprising the compound according to any one of [1] to

[14] . [Example]

[0131] The features of the present invention will be explained in more detail below with reference to examples. The materials, processing details, processing procedures, etc. shown below can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below. The emission characteristics were evaluated using a source meter (Keithley: 2400 series), a semiconductor parameter analyzer (Agilent Technologies: E5273A), an optical power meter (Newport: 1930C), an optical spectrometer (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3), and a streak camera (Hamamatsu Photonics K.K.: C4334). The radiative rate constant k from the excited singlet state of the compound used in the examples r , the nonradiative rate constant from the excited triplet state k nr T , the rate constant k for intersystem crossing from the excited singlet state to the excited triplet state ISC , the rate constant k for reverse intersystem crossing from the excited triplet state to the excited singlet state RISC was calculated from the lifetimes of the prompt component (normal fluorescent component) and delayed component, and the luminescence quantum yield before and after argon bubbling. The lowest excited singlet energy level (E S1 ) and the lowest excited triplet energy level (E T1 ) difference ΔE ST is the lowest excited singlet energy level (E S1 ) and the lowest excited triplet energy level (E T1 ) is calculated using the following method, and ΔE ST =E S1 -E T1 was calculated by (1) The lowest excited singlet energy level (E S1 ) Toluene solution of the compound to be measured (concentration 10 -5A sample was prepared using a solution of 1000 mol / L. The fluorescence spectrum of this sample was measured at room temperature (300K). The fluorescence spectrum has emission on the vertical axis and wavelength on the horizontal axis. A tangent line was drawn to the rising edge of the short wavelength side of this emission spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis was calculated. This wavelength value was converted to an energy value using the following conversion formula, and the value was determined as E S1 It was decided. Conversion formula: E S1 [eV]=1239.85 / λedge The emission spectrum was measured using an LED light source (M340L4 manufactured by Thorlabs) as an excitation light source and a detector (PMA-50 manufactured by Hamamatsu Photonics KK). (2) The lowest excited triplet energy level (E T1 ) The lowest excited singlet energy level (E S1 The same sample used in the measurement of ) was cooled to 77 [K] using liquid nitrogen, and the sample for phosphorescence measurement was irradiated with excitation light (340 nm), and the phosphorescence was measured using a detector. The emission from 100 milliseconds after irradiation with excitation light was taken as the phosphorescence spectrum. A tangent line was drawn to the rising edge on the short wavelength side of this phosphorescence spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis was calculated. This wavelength value was converted to an energy value using the following conversion formula, and the value E T1 It was decided. Conversion formula: E T1 [eV]=1239.85 / λedge The tangent to the rising edge of the phosphorescence spectrum on the short wavelength side was drawn as follows: When moving along the spectral curve from the short wavelength side of the phosphorescence spectrum to the shortest maximum of the spectral maxima, consider the tangent at each point on the curve toward the long wavelength side. The slope of this tangent increases as the curve rises (i.e., as the vertical axis increases). The tangent drawn at the point where this slope reaches its maximum was taken as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Note that a maximum point having a peak intensity of 10% or less of the maximum peak intensity of the spectrum was not included in the above-mentioned maximum value on the shortest wavelength side, and the tangent drawn at the point where the slope value is the maximum and closest to the maximum value on the shortest wavelength side was defined as the tangent to the rising edge on the short wavelength side of the phosphorescence spectrum.

[0132] Compound synthesis (Synthesis Example 1) Synthesis of Compound 1 [ka]

[0133] Compound z was synthesized by a method equivalent to that described in Adv. Opt. Mater. 4, 688-693 (2016). Next, under a nitrogen atmosphere, 3,6-dimethylcarbazole (0.39 g, 1.98 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.08 g, 1.98 mmol) in tetrahydrofuran (20 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound z (0.5 g, 0.79 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 3:2) to obtain compound 1 (0.79 g, 0.75 mmol, 95% yield) as a yellow solid. 1 H NMR: (500 MHz, acetone-d6): δ (ppm) = 7.83 (d, J = 8.2 Hz, 4H), 7.71 (d, J = 7.1 Hz, 4H), 7.64 (d, J = 8.3 Hz, 2H), 7.45 (d, J = 8.4 Hz, 2H), 7.34 (d, J = 7.2 Hz, 2H), 7.09 (m, 12H), 6.72 (t, J = 7.9 Hz, 2H), 6.62 (d, J = 8.4 Hz, 2H), 6.45 (d, J = 8.3 Hz, 4H), 2.11 (s, 12H)

[0134] (Synthesis Example 2) Synthesis of Compound 2 [ka]

[0135] Under a nitrogen atmosphere, 3,6-di-tert-butylcarbazole (1 g, 3.58 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.14 g, 3.58 mmol) in tetrahydrofuran (20 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound z (1.04 g, 1.63 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 1:1) to obtain compound 2 (1.8 g, 1.56 mmol, 96% yield) as a yellow solid.

[0136] (Synthesis Example 3) Synthesis of Compound 3 [ka]

[0137] Under a nitrogen atmosphere, 3,6-diphenylcarbazole (1 g, 3.15 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.13 g, 3.15 mmol) in tetrahydrofuran (20 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound z (0.8 g, 1.26 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 3:2) to obtain compound 3 (1.36 g, 1.10 mmol, 87% yield) as a yellow solid. 1H NMR: (500 MHz, acetone-d6): δ (ppm) = 7.82 (m, 14H), 7.72 (d, J = 8.7 Hz, 4H), 7.45 (m, 8H), 7.35 (m, 10H), 7.26 (t, J = 8.6 Hz, 4H), 7.16 (t, J = 8.3 Hz, 4H), 7.10 (t, J = 7.9 Hz, 4H), 6.98 (d, J = 8.6 Hz, 4H), 6.75 (m, 4H)

[0138] (Synthesis Example 4) Synthesis of Compound 4 [ka]

[0139] Compound y was synthesized by a method equivalent to that described in Adv. Opt. Mater. 4, 688-693 (2016). Next, under a nitrogen atmosphere, 3,6-dimethylcarbazole (0.37 g, 1.92 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.08 g, 1.92 mmol) in tetrahydrofuran (20 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound y (1.0 g, 1.28 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 3:2) to obtain compound 4 (1.08 g, 1.13 mmol, 88% yield) as a yellow solid.

[0140] (Synthesis Example 5) Synthesis of Compound 5 [ka]

[0141] Under a nitrogen atmosphere, 3,6-di-tert-butylcarbazole (0.54 g, 1.92 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.08 g, 1.92 mmol) in tetrahydrofuran (20 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound y (1.0 g, 1.28 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 3:2) to obtain compound 5 (1.16 g, 1.11 mmol, 87% yield) as a yellow solid.

[0142] (Synthesis Example 6) Synthesis of Compound 6 [ka]

[0143] Under a nitrogen atmosphere, 3,6-diphenylcarbazole (0.61 g, 1.92 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.08 g, 1.92 mmol) in tetrahydrofuran (20 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound y (1.0 g, 1.28 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 3:2) to obtain compound 6 (1.18 g, 1.09 mmol, 85% yield) as a yellow solid. 1 H NMR: (500 MHz, acetone-d6): δ (ppm) = 7.82 (m, 8H), 7.75 (m, 4H), 7.67 (t, J = 7.8 Hz, 4H), 7.45 (m, 4H), 7.35 (m, 8H), 7.25 (t, J = 8.0 Hz, 2H), 7.11 (m, 8H), 6.95 (d, J = 8.6 Hz, 2H), 6.74 (m, 4H), 6.66 (t, J = 7.8 Hz, 4H)

[0144] (Synthesis Example 7) Synthesis of Compound 7 [ka]

[0145] Under a nitrogen atmosphere, 3,9'-bicarbazole (0.66 g, 1.98 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.08 g, 1.98 mmol) in tetrahydrofuran (15 mL) and stirred at room temperature for 1 hour. The mixture was cooled to 0 °C, and compound z (0.5 g, 0.79 mmol) was added. The mixture was stirred at 50 °C for 12 hours. The reaction mixture was quenched by adding ice water and filtered to obtain the crude product. The crude product was purified by silica gel column chromatography (toluene:hexane = 1:1) to obtain compound 7 (0.54 g, 0.43 mmol, 54% yield) as a yellow solid.

[0146] (Synthesis Example 8) Synthesis of Compound 35 [ka]

[0147] Under a nitrogen stream, tri(o-tolyl)phosphine (0.525 g, 1.72 mmol) and tris(dibenzylideneacetone)palladium(0) (1.57 g, 1.72 mmol) were added to a toluene solution (50 mL) of tributyltin chloride (5.06 g, 4.45 mL, 13.78 mmol) and 4-bromo-2,3,5,6-tetrafluorobenzonitrile (2.92 g, 11.50 mmol), and the mixture was heated to 100 °C and stirred for 21 hours. The mixture was then cooled to room temperature, quenched with water, extracted with ethyl acetate, and filtered through a Celite pad. The organic layer was then washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (dichloromethane:hexane = 1:2) to give compound a (2.42 g, 9.63 mmol, 83.7% yield) as a white solid. 1 H-NMR (500 MHz, CDCl 3、δ):7.56-7.51(m,3H),7.48-7.45(m,2H) ASAP mass spectrum analysis: Calculated 251.0, observed 251.1

[0148] Under a nitrogen stream, 9H-carbazole (0.397 g, 2.38 mmol) was added to a solution (10 mL) of sodium hydride (60% dispersion in mineral oil, 0.125 g, 3.14 mmol) in tetrahydrofuran, and the mixture was stirred at room temperature for 1 hour. The mixture was cooled to -50 °C, and compound a (0.3 g, 1.19 mmol) was added. The cooling bath was removed, and the mixture was stirred for 22 hours while gradually warming to room temperature. The reaction mixture was quenched by adding ice water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (chloroform:hexane = 1:2) to give compound b (0.486 g, 0.89 mmol, 74.8% yield) as a yellow solid. 1 H-NMR (500 MHz, CDCl 3、 δ):8.16(d,J=7.5Hz,4H), 7.62-7.59(m,2H), 7.54-7.49(m,7H), 7.38(dt,J=7.5Hz,1.0Hz,4H),7.30(d,J=7.5Hz,4H), ASAP mass spectrum analysis: theoretical 545.2, observed 545.2

[0149] [ka]

[0150] A 100 mL three-neck flask was charged with 0.575 g (2.36 mmol) of 3-phenyl-9H-carbazole, 0.702 g (3.94 mmol) of potassium carbonate, and 0.5 g (0.788 mmol) of compound b, and the atmosphere inside the flask was replaced with nitrogen. 10 mL of dehydrated 1-methyl-2-pyrrolidone was added to this mixture, which was then heated and stirred at 100°C under a nitrogen atmosphere for 12 hours. After stirring, the mixture was returned to room temperature, water was added, and the mixture was suction filtered. The resulting solid was dissolved in toluene and purified by silica gel column chromatography. The resulting fraction was concentrated and recrystallized from a mixed solvent of chloroform and acetonitrile to give compound 35 (yield: 0.60 g, 77%) as a pale yellow solid. 1 H NMR(500MHz,CDCl3,δ):7.77(d,J=1.2,2H),7.55-7.69(m,4H),7.60(d,J=7.5Hz,2H),7.51(dd,J=8.5Hz,4H),7.4 2(td,J=8.0,J=2.0,4H),7.32-6.94(m,24H),6.75(d,J=7.5,2H),6.55(td,J=7.51,J=1.2,1H),6.46(t,J=7.5,2H) ASAP mass spectrum analysis: theoretical 991.37, observed 992.39

[0151] (Synthesis Example 9) Synthesis of Compound 38 [ka]

[0152] Under a nitrogen stream, compound b (0.45 g, 0.825 mmol) obtained in Synthesis Example 8 was added to a solution (10 mL) of 3,6-diphenylcarbazole (0.66 g, 2.06 mmol) and potassium carbonate (0.43 g, 3.11 mmol) in 1-methyl-2-pyrrolidone, and the mixture was stirred at 100°C for 48 hours. The mixture was returned to room temperature, quenched by adding water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (chloroform:hexane = 1:1) to give compound 38 (0.575 g, 0.502 mmol, 60.9% yield) as a yellow solid. 1 H-NMR (500 MHz, CDCl 3、 δ):7.81(d,J=1.5Hz,4H), 7.72-7.70(m,4H), 7.54-7.52(m,8H), 7.43(t,J=7.5Hz,8H), 7.32( t,J=7.5Hz, 4H), 7.29-7.06(m,20H), 6.86-6.83(m,2H), 6.61-6.58(m,1H), 6.56-6.52(m,2H) ASAP mass spectrum analysis: theoretical 1143.4, observed 1143.4

[0153] (Synthesis Example 10) Synthesis of Compound 48 [ka]

[0154] Under a nitrogen stream, 3,6-diphenylcarbazole (0.95 g, 2.97 mmol) was added to a solution (10 mL) of sodium hydride (60% dispersion in mineral oil, 0.315 g, 7.88 mmol) in tetrahydrofuran, and the mixture was stirred at room temperature for 1 hour. This mixture was cooled to -50 °C, and compound a (0.3 g, 1.19 mmol) obtained in Synthesis Example 8 was added. The cooling bath was removed, and the mixture was stirred for 17 hours while gradually warming to room temperature. The reaction mixture was quenched by adding ice water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (chloroform:hexane = 1:2) to give compound c (0.308 g, 0.362 mmol, yield 30.4%) as a yellow solid and compound d (0.70 g, 0.609 mmol, yield 51.2%) as a yellow solid. Compound c: 1 H-NMR (500 MHz, CDCl 3、 δ):8.42(d,J=1.0Hz,4H), 7.80(dd,J=7.0Hz,2.0Hz,4H),7.74(dd,J=8.0Hz,1.0Hz, 8H), 7.68-7.65(m,2H), 7.58-7.48(m,11H), 7.42(d,J=8.0Hz, 4H), 7.40-7.36(m,4H) ASAP mass spectrum analysis: 849.3 theoretical, 849.3 observed Compound d: 1 H-NMR (500 MHz, CDCl 3、 δ):8.47(d,J=1.5Hz,2H), 7.89(dd,J=8.5Hz,2.0Hz,2H), 7.83(d,J=1.5Hz,2H), 7.80-7.78(m,4H), 7.74(d,J=1.5Hz, 2H), 7.66(d,J=8.0Hz, 2H), 7.54-7.52(m,4H), 7.48-7.44(m,8H), 7.42-7.27(m,18H), 7.19-7.16(m,7H), 7.01(d,J=8.0Hz, 2H) ASAP mass spectrum analysis: theoretical 1148.4, observed 1148.4

[0155] [ka]

[0156] Compound c (0.30 g, 0.35 mmol) was added to a solution (10 mL) of 9H-carbazole (0.175 g, 1.05 mmol) and potassium carbonate (0.184 g, 1.33 mmol) in 1-methyl-2-pyrrolidone under a nitrogen stream, and the mixture was stirred at 100 °C for 20 hours. The mixture was returned to room temperature, quenched by adding water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (chloroform:hexane = 1:2) to give compound 48 (0.317 g, 0.277 mmol, 79.1% yield) as a yellow solid. 1 H-NMR (500 MHz, CDCl 3、 δ):7.96(d,J=1.5Hz,4H), 7.59-7.55(m,12H), 7.45(t,J=7.5Hz,8H), 7.35-7.31(m,12H), 7.0 7-7.01(m,4H), 7.00-6.94(m,8H), 6.76-6.74(m,2H), 6.58-6.54(m, 1H), 6.45(t,J=8.0Hz, 2H) ASAP mass spectrum analysis: theoretical 1143.4, observed 1143.3

[0157] (Synthesis Example 11) Synthesis of Compound 55 [ka]

[0158] Under a nitrogen stream, 9H-carbazole (4.78 g, 28.59 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.90 g, 22.51 mmol) in tetrahydrofuran (120 mL) and stirred for 1 hour. The mixture was cooled to -50 °C, and 2,3,5,6-tetrafluorobenzonitrile (2.50 g, 14.28 mmol) was added. The cooling bath was removed, and the mixture was stirred for 110 hours while gradually warming to room temperature. The reaction mixture was quenched by adding ice water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (toluene:hexane = 1:1) to give compound e (2.42 g, 5.15 mmol, 36.1% yield) as a pale yellow solid. 1 H-NMR (500 MHz, CDCl 3、 δ):8.16(d,J=7.5Hz,4H), 7.68(t,J H-F =9.0Hz,1H), 7.51(dt,J=7.5Hz,1.0Hz,4H), 7.38(dt,J=7.5Hz,1.0Hz,4H),7.23(d,J=7.5Hz,4H), ASAP mass spectrum analysis: Calculated 469.1, Observed 469.1

[0159] Compound e (0.34 g, 0.724 mmol) was added to a solution (9 mL) of 3,6-diphenylcarbazole (0.57 g, 1.81 mmol) and potassium carbonate (0.38 g, 2.75 mmol) in 1-methyl-2-pyrrolidone under a nitrogen atmosphere, and the mixture was stirred at 100 °C for 24 hours. The mixture was returned to room temperature, quenched by adding water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (toluene:hexane = 1:1) to give compound 55 (0.515 g, 0.482 mmol, 66.6% yield) as a yellow solid. 1 H-NMR (500 MHz, CDCl 3、δ):8.54(s,1H), 8.04(s,4H), 7.81(d,J=7.5Hz,4H), 7.61-7.59(m,8H),7. 47-7.39(m,20H),7.36-7.33(m,4H),7.25-7.22(m,4H),7.18-7.15(m,4H) ASAP mass spectrum analysis: theoretical 1067.4, observed 1067.4

[0160] (Synthesis Example 12) Synthesis of Compound 108 [ka]

[0161] A 100 mL three-neck flask was charged with 1.56 g (9.00 mmol) of 3,6-dimethyl-9H-carbazole and 0.400 g of sodium hydride (60% mineral oil dispersion, 1.00 mmol), and the atmosphere in the flask was replaced with nitrogen. 80 mL of dehydrated tetrahydrofuran was added to this mixture, which was then stirred under a nitrogen atmosphere for 1 hour, followed by the addition of 0.8 g (4.00 mmol) of tetrafluoroterephthalonitrile. This mixture was heated and stirred at 50°C for 12 hours, then returned to room temperature. Water was added, and the mixture was subjected to suction filtration to obtain a solid. The resulting solid was purified by sublimation to obtain compound f (yield: 0.8 g, 36%) as a red solid. A 100 mL three-neck flask was charged with 0.696 g (2.18 mmol) of 3,6-diphenyl-9H-carbazole, 0.647 g (3.63 mmol) of potassium carbonate, and 0.4 g (0.726 mmol) of compound f, and the atmosphere inside the flask was replaced with nitrogen. 10 mL of dehydrated 1-methyl-2-pyrrolidone was added to the mixture, which was then heated and stirred at 100°C under a nitrogen atmosphere for 12 hours. After stirring, the mixture was returned to room temperature, water was added, and the mixture was suction filtered. The resulting solid was recrystallized from a mixed solvent of chloroform and acetonitrile to give compound 108 (yield: 0.62 g, 74%) as a red solid. 1H NMR(500MHz,CDCl3,δ):8.01(d,J=1.5Hz,4H),7.62(dd,J=8.0Hz,J=1.0Hz,8H),7.50-7.43(m,12H),7.41(dd,J=7.5,J =1.5,4H),7.37(t,J=7.5,4H),7.33(d,J=8.5Hz,4H),7.17(d,J=8Hz,4H),6.99(dd,J=8Hz,J=1.5Hz,4H),2.41(s,12H) ASAP mass spectrum analysis: theoretical 1148.46, observed 1150.51

[0162] (Synthesis Example 13) Synthesis of Compound 149 [ka]

[0163] Compound d (0.65 g, 0.566 mmol) was added to a solution (10 mL) of 9H-carbazole (0.142 g, 0.849 mmol) and potassium carbonate (0.18 g, 1.30 mmol) in 1-methyl-2-pyrrolidone under a nitrogen atmosphere, and the mixture was stirred at 100 °C for 120 hours. The mixture was then cooled to room temperature and quenched by adding water. The resulting precipitate was washed with methanol and purified by silica gel column chromatography (toluene:hexane = 3:2) to give compound 149 (0.284 g, 0.219 mmol, 38.7% yield) as an orange solid. 1 H-NMR (500 MHz, CDCl 3、 δ):7.98(d,J=1.0Hz,2H), 7.85(d,J=1.0Hz,2H), 7.73(d,J=2.0Hz,2H), 7.60-7.58(m,6H), 7.49-7.44(m,12H), 7.39-7.24(m,20 H), 7.19-7.16(m,4H), 7.12-7.09(m,2H), 7.05-6.97(m,6H), 6.93(d,J=8.0Hz, 2H), 6.64(t,J=8.0Hz, 1H), 6.58(t,J=8.0Hz, 2H) ASAP mass spectrum analysis: theoretical 1295.5, observed 1295.2

[0164] (Synthesis Example 14) Synthesis of Compound 313 [ka]

[0165] Under a nitrogen stream, 9H-carbazole (1.42 g, 8.49 mmol) was added to a solution (45 mL) of sodium hydride (60% dispersion in mineral oil, 0.265 g, 6.63 mmol) in tetrahydrofuran, and the mixture was stirred at room temperature for 1 hour. The mixture was cooled to -50 °C, and 2,3,5,6-tetrafluoro-4-pyridinecarbonitrile (0.749 g, 4.25 mmol) was added. The cooling bath was removed, and the mixture was stirred for 24 hours while gradually warming to room temperature. The reaction mixture was quenched by adding ice water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was reprecipitated with ethyl acetate / methanol to give compound g (0.989 g, 2.10 mmol, 49.4% yield) as an orange solid. 1 H-NMR (500 MHz, CDCl 3、 δ):8.19(d,J=7.5Hz,2H), 8.15(d,J=7.5Hz,2H), 7.69-7.67(m,2H), 7.54 (dt,J=7.5, 1.0Hz, 4H), 7.44(dt,J=7.5, 1.5Hz, 4H), 7.30(d,J=8.0Hz, 2H) 13 C-NMR (125 MHz, CDCl 3、 δ):154.66, 154.64, 152.67, 152.65, 150.66, 150.62, 148.47, 148.43, 139.63, 138.59, 126.80, 126.76, 125.14, 124.55, 1 22.71, 122.14, 120.98, 120.54, 120.02, 119.75, 115.74, 115.69, 115.62, 115.57, 111.53, 111.50, 109.74, 108.76, 108.73 ASAP mass spectrum analysis: 470.1 theoretical, 470.1 observed

[0166] Compound g (0.50 g, 1.06 mmol) was added to a solution (13 mL) of 3,6-diphenylcarbazole (0.849 g, 2.66 mmol) and potassium carbonate (0.55 g, 3.99 mmol) in 1-methyl-2-pyrrolidone under a nitrogen stream, and the mixture was stirred at 100 °C for 48 hours. The mixture was returned to room temperature, quenched by adding water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (toluene:hexane = 1:1) to give compound 313 (0.963 g, 0.901 mmol, 84.7% yield) as an orange solid. 1 H-NMR (500 MHz, CDCl 3、 δ):8.07(d,J=1.5Hz,2H), 8.00(d,J=1.5Hz,2H), 7.84(d,J=7.0Hz,2H), 7.76(d,J=7.0Hz,2H), 7.6 3(d,J=8.0Hz,4H)7.58(d,J=8.0Hz,4H),7.54-7.43(m,14H),7.38-7.32(m,8H),7.30-7.07(m,10H) ASAP mass spectrum analysis: theoretical 1068.4, observed 1068.3

[0167] (Synthesis Example 15) Synthesis of Compound 11 [ka]

[0168] Under a nitrogen stream, 3-methyl-9H-carbazole (0.51 g, 0.83 mmol) was added to a solution (15 mL) of sodium hydride (60% dispersion in mineral oil, 0.15 g, 3.78 mmol) in tetrahydrofuran, and the mixture was stirred at room temperature for 1 hour. The mixture was cooled to 50°C, and compound z (0.6 g, 0.95 mmol) was added. The mixture was heated to 50°C and stirred for 12 hours. Water was added to the reaction mixture to precipitate the product, and the precipitate was collected by filtration. The collected mixture was purified by silica gel column chromatography (toluene) to obtain compound B (0.65 g, 0.68 mmol, 71.9% yield). 1H-NMR (500 MHz, CDCl 3、 δ):7.76-7.72(m,4H), 7.30-7.12(m,10H), 7.10-7.02(m,10H), 6.98(t,J=8.5Hz,2H), 6.91(t ,J=8.5Hz,2H), 6.76-6.71(m,4H), 6.61-6.53(m,4H), 6.41(t,J=8.5Hz,2H), 2.17-2.16(m,6H) ASAP mass spectrum analysis: theoretical 956.4, observed 957.3

[0169] (Synthesis Example 16) Synthesis of Compound 150 [ka]

[0170] Compound e (0.50 g, 1.07 mmol) was added to a solution (10 mL) of 3-methyl-9H-carbazole (0.57 g, 3.20 mmol) and potassium carbonate (0.95 g, 5.33 mmol) in 1-methyl-2-pyrrolidone under a nitrogen stream, and the mixture was stirred at 120 °C for 36 hours. The mixture was returned to room temperature, and water was added to cause precipitation. The precipitate was collected by filtration. The collected mixture was purified by silica gel column chromatography (toluene) to obtain compound A (0.40 g, 0.51 mmol, yield 47.4%). 1 H-NMR (500 MHz, CDCl 3、 δ):8.38(s,1H), 7.83-7.79(m,4H), 7.75-7.72(m,2H), 7.58(d,J=4.0Hz,2H), 7.43-7.33( m,4H), 7.30-7.11(m,12H), 7.10-7.03(m,4H), 7.00-6.93(m,2H), 2.41(s,3H), 2.39(s,3H) ASAP mass spectrum analysis: theoretical 791.3, observed 792.4

[0171] (Synthesis Example 17) Synthesis of Compound 151 [ka]

[0172] Under an argon atmosphere, 4-bromo-2,3,5,6-tetrafluorobenzonitrile (3 g, 11.9 mmol) was dissolved in toluene (100 mL) and 0.3 M aqueous sodium carbonate (67 mL) was added. Pd(PPh3)4 (1.38 g, 1.19 mmol) and 5'-m-tetraphenylboronic acid (3.92 g, 14.3 mmol) were added, and the mixture was heated to reflux overnight. After cooling to room temperature, the organic layer was separated, and the aqueous layer was extracted with dichloromethane. The combined organic layer was dried over anhydrous sodium sulfate. The desiccant was filtered, and the filtrate was concentrated by distillation under reduced pressure to obtain the crude product. The resulting crude product was purified by silica gel chromatography (hexane:chloroform = 4:1) to obtain compound I (2.37 g, 5.88 mmol, 49.4%) as a white powder.

[0173] Under an argon atmosphere, 9H-carbazole (0.83 g, 4.96 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.2 g, 4.96 mmol) in tetrahydrofuran (50 mL) and stirred at room temperature for 1 hour. This mixture was cooled to -50 °C, and compound i (1.0 g, 2.48 mmol) was added. The cooling bath was removed, and the mixture was stirred for 2 hours while gradually returning to room temperature. The reaction mixture was quenched by adding ice water, extracted with dichloromethane, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (hexane:toluene = 3:2) to give compound j (0.96 g, 1.38 mmol, 55.6%) as a white solid.

[0174] Under an argon atmosphere, 3,6-diphenylcarbazole (1.32 g, 4.14 mmol) was added to a solution of sodium hydride (60% dispersion in mineral oil, 0.17 g, 4.14 mmol) in tetrahydrofuran (30 mL) and stirred at room temperature for 1 hour. Compound 2 (0.96 g, 1.38 mmol) was added, and the mixture was heated at 50 °C overnight. The reaction mixture was quenched by adding ice water, and the solid was collected. The resulting solid was purified by silica gel column chromatography (toluene) to give compound 151 (1.10 g, 0.85 mmol, 61.5%) as a yellow solid.

[0175] (Synthesis Example 18) Synthesis of Compound 152 [ka]

[0176] Under a nitrogen stream, 9H-carbazole (0.80 g, 4.78 mmol) was added to a solution (15 mL) of sodium hydride (60% dispersion in mineral oil, 0.17 g, 7.17 mmol) in tetrahydrofuran and stirred at room temperature for 1 hour. The mixture was cooled to -50 °C, and compound 1 (0.4 g, 1.59 mmol) was added. The cooling bath was removed, and the mixture was stirred for 24 hours while gradually warming to room temperature. The reaction mixture was quenched by adding ice water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure, and the resulting mixture was purified by silica gel column chromatography (hexane:toluene = 2:1) to give compound h (0.69 g, 1.00 mmol, 62.9% yield) as a yellow solid. 1 H-NMR (500 MHz, CDCl 3、 δ):8.20(d,J=8.5Hz,2H), 7.72-7.68(m,2H), 7.61-7.56(m,4H), 7.51(d,J =8.5Hz,2H), 7.44(t,J=8.5Hz,2H), 7.16-7.11(m,4H), 7.10-6.94(m,13H) ASAP mass spectrum analysis: Calculated 692.2, Observed 692.1

[0177] Compound h (0.50 g, 0.72 mmol) was added to a solution (10 mL) of 3,6-diphenylcarbazole (0.35 g, 1.08 mmol) and potassium carbonate (0.20 g, 1.44 mmol) in 1-methyl-2-pyrrolidone under a nitrogen stream, and the mixture was stirred at 100 °C for 48 hours. The mixture was then cooled to room temperature and quenched with water. The resulting precipitate was washed with methanol. This was then reprecipitated with chloroform / methanol to give compound 3 (0.56 g, 0.564 mmol, 77.6% yield) as a yellow solid. 1H-NMR (500 MHz, CDCl 3、 δ):7.80(d,J=1.5Hz,2H), 7.73-7.68(m,4H), 7.59-7.57(m,2H), 7.52(dd,J=8.0Hz,J=1.5Hz,4H), 7.42(t,J=8.0Hz,4H), 7.33-7.22(m, 6H), 7.19(dd,J=8.0Hz,J=1.5Hz,2H), 7.14-6.92(m,16H), 6.74(dd,J=8.0Hz,J=1.5Hz,2H), 6.55(t,J=8.0Hz,1H), 6.48(t,J=8.0Hz,2H) ASAP mass spectrum analysis: theoretical 991.4, observed 991.8

[0178] Fabrication and evaluation of organic photoluminescence devices Example 1: Preparation of an organic photoluminescence device using compound 1 Compound 1 in toluene (concentration 10 -5 mol / L) was prepared. In addition, a quartz substrate was vacuum-deposited at a vacuum of 5×10 -4 A thin film of Compound 1 was formed to a thickness of 50 nm under conditions of 0.1 Pa or less to prepare an organic photoluminescence device.

[0179] Examples 2 to 6: Preparation of organic photoluminescence devices using compounds 2 to 6 Except for using compounds 2 to 6 instead of compound 1, toluene solutions of compounds 2 to 6 were prepared in the same manner as in Example 1, and thin films of compounds 2 to 6 were formed to prepare organic photoluminescence devices.

[0180] (Comparative Examples 1 to 3) Preparation of organic photoluminescence devices using comparative compounds 1 to 3 Toluene solutions of compounds 2 to 6 were prepared in the same manner as in Example 1, except that the following comparative compounds 1 to 3 were used instead of compound 1, and thin films of comparative compounds 1 to 3 were formed to prepare organic photoluminescence devices.

[0181] [ka]

[0182] The absorption spectra of the toluene solutions prepared in Examples 1 to 3, 4, and 6 and Comparative Example 1 are shown in Figure 2, the fluorescence spectra with 340 nm excitation light are shown in Figure 3, the transient decay curves of emission with 340 nm excitation light are shown in Figure 4, and the phosphorescence spectra with 340 nm excitation light are shown in Figure 5. The compounds used in each Example and their optical properties are shown in Table 9. In Table 9, compounds for which no measurements were performed are indicated by "-".

[0183] [Table 9]

[0184] As shown in Table 9, compounds 1 to 6 have a higher reverse intersystem crossing rate constant k compared to comparative compound 1. RISC was much larger, and had a higher PL quantum yield (photoluminescence quantum yield) than the comparative compounds 1 to 3.

[0185] Examples 7 to 13: Preparation and evaluation of organic photoluminescence devices using compounds 11, 35, 38, 55, 150, 151, and 152 and host materials The emitting materials and host materials listed in Table 10 were evaporated from different evaporation sources at a vacuum of 5×10 -4 A 50 nm-thick thin film was formed on a quartz substrate by co-evaporation at temperatures below 1000 Pa to prepare an organic photoluminescence device. The maximum emission wavelength of the fluorescence spectrum of each device, PL quantum yield under a nitrogen atmosphere, delayed fluorescence lifetime, and ΔE ST The results are shown in Table 10. All of them had high PL quantum yields.

[0186] [Table 10]

[0187] (Examples 14 and 15) Preparation and evaluation of organic photoluminescence devices using compounds 108 and 313 and host materials Organic photoluminescence devices were fabricated and evaluated in the same manner as in Examples 7 to 13, except that Compound 108 or Compound 313 was used as the light-emitting material and mCBP was used as the host material. The delayed fluorescence lifetime of the device using compound 108 was 8.9 ms, ΔE ST The delayed fluorescence lifetime of the device using compound 313 was 4.0 ms, and ΔE ST was 0.11 eV.

[0188] Fabrication and evaluation of organic electroluminescence devices Example 16: Preparation and evaluation of organic electroluminescence device using compound 3 Each thin film was deposited by vacuum deposition on a glass substrate with an anode made of indium tin oxide (ITO) with a thickness of 50 nm, at a vacuum of 2×10 -5 The laminate was made at 1000 Pa. First, a 60-nm thick HATCN was deposited on ITO to form a hole-injection layer. A 30-nm thick TrisPCz was deposited on top of that to form a hole-transport layer. A 5-nm thick electron-blocking layer was then deposited on top of that. Compound 3 and mCBP were co-evaporated from separate sources to form a 30-nm thick emissive layer. The concentration of compound 3 was 20 wt%. A 10-nm thick DTRZ hole-blocking layer was then deposited on top of that. A 30-nm thick electron-transport layer was then co-evaporated from separate sources with BpyTP2 and Liq (7:3 by weight). A 2-nm thick Liq layer was then deposited on top of that, followed by a 100-nm thick aluminum (Al) cathode. By the above steps, an organic electroluminescence device of Example 16 was produced.

[0189] Example 17: Preparation and evaluation of organic electroluminescence device using compound 6 An organic electroluminescence device of Compound 8 was prepared in the same manner as in Example 16, except that Compound 6 was used instead of Compound 3.

[0190] Comparative Example 4: Preparation and evaluation of organic electroluminescence device using comparative compound 1 An organic electroluminescence device of Comparative Example 4 was produced in the same manner as in Example 16, except that Comparative Compound 1 was used instead of Compound 3.

[0191] The fluorescence spectra of the organic electroluminescence devices produced in Examples 16 and 17 and Comparative Example 4 are shown in FIG. 6, their current density-voltage characteristics in FIG. 7, their current density-external quantum efficiency characteristics in FIG. 8, and the time change in luminance in FIG. 9. As shown in FIG. 7, the organic electroluminescence devices of Examples 16 and 17 achieved high external quantum efficiencies of 19.4% and 17.3%, respectively. These external quantum efficiencies were even higher than the external quantum efficiency (16.0%) of the organic electroluminescence device of Comparative Example 4, which used a light-emitting material in which all groups with negative Hammett σp values ​​were the same. Furthermore, as shown in FIG. 9, the organic electroluminescence devices of Examples 16 and 17 had significantly longer lifetimes than the organic electroluminescence device of Comparative Example 4.

[0192] Examples 18 to 25: Preparation and evaluation of organic electroluminescence devices using compounds 11, 13, 38, 55, 150, 151, 152, and 313 Each thin film was deposited by vacuum deposition on a glass substrate with an anode made of indium tin oxide (ITO) with a thickness of 50 nm, at a vacuum of 2×10 -5 The laminate was made at 1000 Pa. First, HATCN was evaporated onto ITO to a thickness of 60 nm to form a hole injection layer, and then TrisPCz was evaporated to a thickness of 15 nm to form a hole transport layer. Subsequently, mCBP was evaporated to a thickness of 5 nm to form an electron blocking layer. Next, the emitting and host materials listed in Table 11 were co-evaporated from different evaporation sources to form a 30 nm thick emitting layer. The concentration of the emitting material was 20 wt%. SF3-TRZ was evaporated to a thickness of 10 nm to form a hole blocking layer, and then SF3-TRZ and Liq (weight ratio 7:3) were co-evaporated from different evaporation sources to a thickness of 30 nm to form an electron transport layer. Liq was then deposited to a thickness of 20 nm, followed by a 100 nm thick aluminum (Al) cathode. Using these processes, eight organic electroluminescent devices, as shown in Table 11, were fabricated. The maximum emission wavelength and luminance of the fluorescence spectrum of each of these organic electroluminescent devices were measured. 2 The results of measuring the external quantum efficiency at each temperature are shown in Table 11. All of the devices had high external quantum efficiency.

[0193] [Table 11]

[0194] Example 26: Preparation and evaluation of organic electroluminescence device using compound 108 An organic electroluminescence device was fabricated in the same manner as in Examples 18 to 25, except that Compound 108 was used as the light-emitting material and mCBP was used as the host material. The maximum emission wavelength was 576 nm.

[0195] The structural formulas of the materials used in the examples are shown below. [ka] [Industrial Applicability]

[0196] The compound of the present invention has high luminous efficiency and is useful as a light-emitting material. By using the compound of the present invention, it is possible to provide a light-emitting element with extremely high luminous efficiency. Therefore, the present invention has high industrial applicability. [Explanation of symbols]

[0197] 1 board 2 Anode 3. Hole injection layer 4. Hole transport layer 5. Light-emitting layer 6 Electron transport layer 7 Cathode

Claims

1. A compound represented by the following general formula (10): 【Chemical 1】 [In the general formula (10), A １ represents a cyano group. R １ ~R ５ satisfies the following condition (A) or (B). (A)R １ ~R ５ each independently represents a group having a negative Hammett σp value (excluding a phenyl group), R １ ~R ５ At least R １ , R ２ , R ４ , R ５ is a group containing a diarylamine structure. (B) R １ ~R ５ At least three of the groups are groups containing a diarylamine structure, but R １ ~R ５ Not all of R are groups containing a diarylamine structure, and the remaining R １ ~R ５ is a group having a positive σp value selected from the group consisting of a cyano group, a phenyl group, and a substituted or unsubstituted heteroaryl group, or a hydrogen atom. In the group containing a diarylamine structure under the condition (A) or (B), two aryl groups constituting the diarylamine structure may be bonded to each other, but the group is not a 9-carbazolyl group having a substituent at least at one of the 1-position and the 8-position; At least one of the plurality of groups containing a diarylamine structure is a group containing a substituted diarylamine structure in which at least one hydrogen atom of an aryl group is substituted with a substituent, and at least one of the plurality of groups containing a diarylamine structure is a group containing an unsubstituted diarylamine structure having a diarylamine structure in common with the substituted diarylamine structure, or a group containing a substituted diarylamine structure having a diarylamine structure in common with the substituted diarylamine structure and in which a substituent bonded to an aryl group in the substituted diarylamine structure is substituted with a substituent having a structure different from that of the substituent, with the proviso that the group containing a diarylamine structure is one in which a nitrogen atom of the diarylamine structure is bonded to a benzene ring by a single bond, or one in which a nitrogen atom of the diarylamine structure is bonded to a benzene ring via a substituted or unsubstituted arylene group. Furthermore, the substituent of the diarylamine structure substituted with a substituent and the substituent of the substituted arylene group are selected from the group consisting of a hydroxy group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkyl-substituted amino group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a trialkylsilyl group having 3 to 20 carbon atoms, a trialkylsilylalkyl group having 4 to 20 carbon atoms, a trialkylsilylalkenyl group having 5 to 20 carbon atoms, a diarylamino group having 1 to 20 carbon atoms, and a carbazolyl group, and the groups may be further substituted with a group selected from the group above. However, some or all of the hydrogen atoms in the molecule represented by general formula (10) ２ H (Deuterium D).

2. The compound according to claim 1, which satisfies the condition (A).

3. The compound according to claim 1, which satisfies the condition (B).

4. R １ ~R ５ The compound of claim 3, wherein one of is a cyano group.

5. R １ ~R ５ 5. The compound according to claim 3 or 4, wherein one of is a phenyl group.

6. The compound according to any one of claims 1 to 5, wherein the group containing a diarylamine structure is a group represented by the following general formula (2): 【Chemistry 2】 [In the general formula (2), R １１ and R １８ is a hydrogen atom, and R １２ ~R １７ each independently represents a hydrogen atom, a hydroxy group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkyl-substituted amino group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a trialkylsilyl group having 3 to 20 carbon atoms, a trialkylsilylalkyl group having 4 to 20 carbon atoms, a trialkylsilylalkenyl group having 5 to 20 carbon atoms, a diarylamino group having 1 to 20 carbon atoms, or a carbazolyl group; R １９ is the bond position.]

7. The first of the plurality of groups containing the diarylamine structure is R １２ ~R １７ at least one of the groups containing a diarylamine structure is a substituent selected from the group consisting of a hydroxy group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkyl-substituted amino group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a trialkylsilyl group having 3 to 20 carbon atoms, a trialkylsilylalkyl group having 4 to 20 carbon atoms, a trialkylsilylalkenyl group having 5 to 20 carbon atoms, a diarylamino group having 1 to 20 carbon atoms, and a carbazolyl group, and the second of the plurality of groups containing a diarylamine structure is R １２ ~R １７ The compound according to claim 6, wherein the one corresponding to the first substituent is a hydrogen atom.

8. The first one is R in the general formula (2). １３ and R １６ The compound according to claim 7, wherein at least one of the following is the substituent:

9. R １２ ~R １７ The compound according to claim 7 or 8, wherein the substituent represented by at least one of the following is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

10. A light-emitting material comprising the compound according to any one of claims 1 to 9.

11. A light-emitting device comprising the compound according to any one of claims 1 to 9.

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