Organic electroluminescence element, thin film, compound, delayed fluorescence phosphor, and organic semiconductor laser

Abstract

An organic electroluminescent element according to the present invention comprises a compound represented by formula (1).

Description

Technical Field

[0001] The present invention relates to an organic electroluminescent element, a thin film, a compound, a delayed phosphor, and an organic semiconductor laser.

Background Art

[0002] Organic electroluminescent elements in the visible spectral region have made remarkable progress. In recent years, there has been increasing interest in organic electroluminescent elements that emit light in the near-infrared (NIR) region (i.e., 700 to 2500 nm). Potential applications of these NIR organic electroluminescent elements are interesting in bioimaging, medical cameras, sensors, security cameras, night vision displays, and information protection displays. In the use in organic electroluminescent elements, highly efficient NIR emitters are required.

[0003] In addition, in research on organic electroluminescent elements, efforts are being actively made toward the realization of organic semiconductor laser elements. In particular, since the development of a compound that emits amplified spontaneous emission (ASE) is essential for the realization of such organic semiconductor laser elements, studies have been reported on investigating the ASE characteristics of various compounds and finding compounds useful as laser materials (see Patent Documents 1 and 2, Non-Patent Documents 1 to 4). As a method for obtaining a laser material with a lower ASE threshold in the more NIR region, a method using a curcuminoid compound has been reported (Patent Document 3).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the compound described in Patent Document 3 did not sufficiently satisfy the emission characteristics of the NIR phosphor for use in organic electroluminescence devices and the reduction of the ASE threshold value of the NIR phosphor for realizing an organic semiconductor laser.

Means for Solving the Problems

[0006] The present invention has been made in view of the above circumstances, and provides a compound, a thin film, a delayed fluorescence phosphor, and an organic electroluminescence device that have excellent light emission characteristics and are excellent in reducing the ASE threshold value of a NIR phosphor. That is, the present invention can be shown as follows.

[0007] [1] An organic electroluminescence device containing a compound represented by the general formula (1). [Chemical formula] (In the general formula (1), X 1 and X 2 each independently represent a halogen atom, a halogenated alkyl group or a halogenated aryl group, and at least one of X 1 and X 2 represents a halogenated alkyl group or a halogenated aryl group. R 1 ~R 6 each independently represent a hydrogen atom or a substituent, and R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 may together represent a ring. R 7 represents a group represented by the following general formula (2) or general formula (3). [Chemical formula] (In the general formula (2), Ar 1 represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group or a heteroaryl-substituted heteroarylene group, and R 8 represents a substituent. A plurality of R 8may be the same or different, and at least one R 8 is an electron-donating group. n8 represents an integer from 1 to the number of substitutable positions in Ar 1 ). [Chemical formula] (In general formula (3), R 9 ~R 13 each independently represents a hydrogen atom or a substituent, and p represents an integer of 0 or 1 to 2.)) [2] The organic electroluminescence element according to [1], wherein the compound represented by the general formula (1) is a compound represented by the following general formula (4). [Chemical formula] (In general formula (4), X 1 , X 2 , and R 2 ~R 6 have the same meanings as in general formula (1). Ar 2 and Ar 3 each independently represent an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group. R 3 and R 4 , R 4 and R 5 may combine together to form a ring, R 2 may combine with Ar 2 to form a ring, and R 6 may combine with Ar 3 to form a ring. R 14 and R 15 each independently represent a substituent, and a plurality of R 14 may be the same or different, and at least one R 14 is an electron-donating group, and a plurality of R 15 may be the same or different, and at least one R 15 is an electron-donating group. n14 represents an integer from 1 to the number of substitutable positions in Ar 2 and n15 represents an integer from 1 to the number of substitutable positions in Ar 3 .) [3] In the general formula (4), R 14 and R 15 at least one of which is a substituted or unsubstituted diarylamino group, the organic electroluminescence device according to [2]. [4] In the general formula (4), Ar 2 and Ar 3 are each independently composed of a benzene structure, a naphthalene structure, an anthracene structure or a fluorene structure, the organic electroluminescence device according to [2] or [3]. [5] The compound represented by the general formula (1) is a compound represented by the following general formula (5), the organic electroluminescence device according to any one of [1] to [4]. [Chemical formula] (In the general formula (5), X 1 , X 2 , and R 2 to R 6 are synonymous with the general formula (1). Ar 4 to Ar 7 each independently represent a substituted or unsubstituted aryl group, and each Ar 4 and each Ar 5 may be the same or different, and each Ar 6 and each Ar 7 may be the same or different. R 16 and R 17 each independently represent a substituent other than a substituted or unsubstituted diarylamino group, and R 16 and R 17 may be the same or different. R 16 and R 2 , R 3 and R 4 , R4 and R 5 , R 6 and R 17 may combine together to form a ring. n16 and n18 each independently represent an integer of 0 or 1 or more, n17 and n19 each independently represent an integer of 1 or more, n16 + n17 is an integer of 1 to 5, and n18 + n19 is an integer of 1 to 5.) [6] R 4 is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a halogen atom, or a group containing a boron difluoride diketonate ring, the organic electroluminescence element according to any one of [1] to [5]. [7] R 3 and R 4 , or R 4 and R 5 are combined together to form a ring, the organic electroluminescence element according to any one of [1] to [6]. [8] The compound represented by the general formula (1) is the compound represented by the following general formula (6), the organic electroluminescence element according to [1].

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[10] The organic electroluminescence device according to any one of [1] to [9], which exhibits a maximum emission wavelength in the range of 700 to 1,500 nm.

[11] An organic semiconductor laser including the organic electroluminescence device according to any one of [1] to

[10] .

[12] The organic semiconductor laser according to

[11] , wherein the organic semiconductor laser has an optical resonator structure composed of a secondary Bragg scattering region surrounded by a primary Bragg scattering region.

[13] A thin film having a layer containing the compound represented by general formula (1) according to [1], the compound represented by general formula (4) according to [2], the compound represented by general formula (5) according to [5], or the compound represented by general formula (6) according to [8] on a substrate.

[14] A compound represented by the following general formula (10). [Chemical formula] (In general formula (10), X 1 , X 2 , and R 2 ~R 6 have the same meaning as in general formula (1). Ar 2 and Ar 3 each independently represent an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group. R 3 and R 4 , R 4 and R 5 may together form a ring, R 2 may combine with Ar 2 to form a ring, and R 6 may combine with Ar 3It may combine to form a ring. R 14 and R 15 each independently represent a substituent containing an aryl group, and multiple Rs 14 may be the same or different, and at least one R 14 is an electron-donating group containing an aryl group, and multiple Rs 15 may be the same or different, and at least one R 15 is an electron-donating group containing an aryl group. n14 represents an integer from 1 to the number of substitutable positions in Ar 2 and n15 represents an integer from 1 to the number of substitutable positions in Ar 3 (.

[15] In the general formula (10), R 14 and R 15 at least one of which is a substituted or unsubstituted diarylamino group, the compound according to

[14] .

[16] A compound represented by the following formula (11).

Chemical formula

[17] A delayed fluorescence phosphor containing the compound according to any one of

[14] to

[16] .

[18] An organic semiconductor laser containing the compound according to any one of

[14] to

[16] .

[19] The organic semiconductor laser according to

[18] , wherein the organic semiconductor laser has an optical resonator structure composed of a secondary Bragg scattering region surrounded by a primary Bragg scattering region. [Effect of the Invention]

[0008] According to the present invention, it is possible to provide a compound, a thin film, a delayed fluorescence phosphor, and an organic electroluminescence element that have excellent light emission characteristics and are excellent in reducing the ASE threshold value of the NIR phosphor. [Brief Description of the Drawings]

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. Further, for example, "1 to 10" represents "1 or more" to "10 or less" unless otherwise specified.

[0011] In the present embodiment, the alkyl group may be linear, branched or cyclic, and a linear or branched alkyl group is preferred. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, still more preferably 1 to 8 carbon atoms, and still more preferably 1 to 6 carbon atoms (for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, n-hexyl group, isohexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group and n-dodecyl group). Examples of the cyclic alkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a bicyclo[2.1.1]hexyl group, and a bicyclo[2.2.1]heptyl group. The alkyl group may be substituted. Examples of the substituent in this case include an alkoxy group, an aryl group, an aryloxy group, an acyl group, a hydroxyl group, a halogen atom, a nitro group, a diarylamino group (such as a 9-carbazolyl group), and a cyano group, and an alkoxy group, an aryl group, and an aryloxy group are preferable.

[0012] In the present embodiment, the alkenyl group may be linear, branched, or cyclic, and a linear or branched alkyl group is preferable. The alkenyl group preferably has 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, still more preferably 2 to 8 carbon atoms, and still more preferably 2 to 6 carbon atoms. Examples of the alkenyl group include a vinyl group, a butadienyl group, a hexatrienyl group, and a 1-cyclohexenyl group. The alkenyl group may be substituted. Examples of the substituent in this case include an alkoxy group, an aryl group, an aryloxy group, an acyl group, a hydroxyl group, a halogen atom, a nitro group, a diarylamino group (such as a 9-carbazolyl group), and a cyano group.

[0013] In the present embodiment, the aryl group may have a structure containing a single aromatic ring or a structure containing two or more aromatic rings condensed with each other. The aryl group preferably has 6 to 22 ring-skeleton-forming carbon atoms, more preferably 6 to 18 ring-skeleton-forming carbon atoms, still more preferably 6 to 14 ring-skeleton-forming carbon atoms, and still more preferably 6 to 10 ring-skeleton-forming carbon atoms. Examples of the aryl group include a phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthranyl group, 2-anthranyl group, 9-anthranyl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 1-pyrenyl group, and 2-pyrenyl group. The aryl group may be substituted. Examples of the substituent in this case include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an acyl group, a hydroxyl group, a halogen atom, a nitro group, a diarylamino group (such as a 9-carbazolyl group), and a cyano group, and an alkyl group, an alkoxy group, an aryl group, and an aryloxy group are preferable.

[0014] In the present embodiment, the heteroaryl group may have a structure containing a single heteroaromatic ring or a structure containing two or more heteroaromatic rings condensed with each other. The heteroaryl group may contain at least one heteroaromatic ring and at least one aromatic ring. The heteroaryl group preferably has 5 to 22 ring skeleton-forming atoms, more preferably 5 to 18 ring skeleton-forming atoms, still more preferably 5 to 14 ring skeleton-forming atoms, and still more preferably 5 to 10 ring skeleton-forming atoms.

[0015] Examples of the heteroaryl group include a 2-thienyl group, 3-thienyl group, 2-furyl group, 3-furyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-pyrazinyl group, 2-quinolyl group, 3-quinolyl group, 4-quinolyl group, 1-isoquinolyl group and 3-isoquinolyl group. Other examples of the heteroaryl group include a benzofuryl group, pyrrolyl group, indolyl group, isoindolyl group, azaindolyl group, benzothienyl group, pyridyl group, quinolinyl group, isoquinolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, oxazolyl group, isoxazolyl group, benzoxazolyl group, thiazolyl group, benzothiazolyl group, isothiazolyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, cinnolinyl group, phthalazinyl group and quinazolinyl group. The heteroaryl group may be substituted. Examples of the substituent in this case include an alkyl group, alkoxy group, aryl group, aryloxy group, hydroxyl group, halogen atom, nitro group, diarylamino group (such as 9-carbazolyl group) and cyano group, and an alkyl group, alkoxy group, aryl group and aryloxy group are preferable.

[0016] In this embodiment, for the alkyl moiety of the alkoxy group, the above alkyl group can be applied, and for the aryl moiety of the aryloxy group, the above aryl group can be applied. In this embodiment, the halogen atom is preferably a fluorine atom, chlorine atom, bromine atom or iodine atom.

[0017] [Compound] The compound of this embodiment has a structure represented by the general formula (1).

[0018] [Chemical formula]

[0019] In the general formula (1), X 1 and X 2 each independently represent a halogen atom, halogenated alkyl group or halogenated aryl group, and X1 and X 2 At least one of them represents a halogenated alkyl group or a halogenated aryl group. X 1 and X 2 One of them is a halogenated alkyl group or a halogenated aryl group, the other is a halogen atom, or X 1 and X 2 Both of them are preferably a halogenated alkyl group or a halogenated aryl group.

[0020] In the halogenated alkyl group, 1 to 3 halogen atoms may be bonded to the terminal carbon of the alkyl group, and 1 to 2 halogen atoms may be bonded to the carbon other than the terminal. As the halogen atom, a fluorine atom, a chlorine atom, or a bromine atom is preferable, and a fluorine atom is more preferable. Specific examples of the halogenated alkyl group include halogenated alkyl groups having 1 to 5 carbon atoms such as trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group, trichloromethyl group, and tribromomethyl group. Fluoroalkyl groups having 1 to 3 carbon atoms such as trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, and perfluoroisopropyl group are preferable, and fluoroalkyl groups having 1 to 2 carbon atoms such as trifluoromethyl group and perfluoroethyl group are more preferable.

[0021] In the halogenated aryl group, 1 to the maximum number of substitutable halogen atoms may be bonded to the carbon of the aryl group. As the halogen atom, a fluorine atom, a chlorine atom, or a bromine atom is preferable, and a fluorine atom is more preferable. Specific examples of the halogenated aryl group include halogenated aryl groups having 6 to 18 carbon atoms such as fluorophenyl groups like monofluorophenyl group, difluorophenyl group, trifluorophenyl group, perfluorophenyl group, fluoronaphthyl groups like perfluoronaphthyl group, chlorophenyl groups like pentylchlorophenyl group, bromophenyl groups like pentylbromophenyl group, etc.; fluorinated aryl groups having 6 to 18 carbon atoms such as fluorophenyl groups like trifluorophenyl group, perfluorophenyl group, fluoronaphthyl groups like perfluoronaphthyl group are preferred; fluorophenyl groups having 6 to 18 carbon atoms such as trifluorophenyl group, perfluorophenyl group are more preferred.

[0022] R 1 ~R 6 each independently represents a hydrogen atom or a substituent. R 1 ~R 6 The substituents of R 1 ~R 6 are preferably a substituted or unsubstituted alkyl group having 1 to 16 carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, a substituted or unsubstituted heteroaryl group having 6 to 18 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 16 carbon atoms, a substituted or unsubstituted aryloxycarbonyl group having 6 to 20 carbon atoms, and a halogen atom. In a preferred embodiment, R 1 is a substituent, and R 2 , R 3 , R 5 and R 6 are hydrogen atoms, and R 4 is a hydrogen atom or a substituent. In a more preferred embodiment, R 1 is a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, and R 2 , R 3 , R 5 and R 6 are hydrogen atoms, and R 4 1 is a substituent, and R 2 、R 3 、R 5 and R 6 are hydrogen atoms, and R 4 is a hydrogen atom or a substituent. In a more preferred embodiment, R 1 is a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, and R 2 、R 3 、R 5 and R 6 are hydrogen atoms, and R 4is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 16 carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, a substituted or unsubstituted heteroaryl group having 6 to 18 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 16 carbon atoms, a substituted or unsubstituted aryloxycarbonyl group having 6 to 20 carbon atoms, a halogen atom, or a group containing a boron difluoride diketonate ring. The carbon atoms of the carbonyl group are not included in the above carbon numbers.

[0023] R 7 represents a group represented by the following formula (2) or general formula (3).

[0024] [Chemical formula]

[0025] In general formula (2), Ar 1 represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group, and R 8 represents a substituent. When there are a plurality of Rs 8 may be the same or different, and at least one R 8 is an electron-donating group. n8 represents an integer from 1 to the number of substitutable positions in Ar 1 .

[0026] Ar in general formula (2) 1 represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group.

[0027] Examples of the arylene group include a phenylene group, a 1-naphthylene group, a 2-naphthylene group, a 1-anthranylene group, a 2-anthranylene group, and a 9-anthranylene group, and a phenylene group, a 1-naphthylene group, and a 2-naphthylene group are preferred. Examples of the aryl-substituted arylene group include a phenyl-substituted phenylene group, a phenyl-substituted 1-naphthylene group, and the like. Two or more aromatic rings in the aryl-substituted arylene group may be bonded to each other directly or via a linking group such as a substituted or unsubstituted methylene group to form a further ring.

[0028] Examples of the heteroaryl-substituted arylene group include a thienyl-substituted phenylene group, a thienyl-substituted 1-naphthylene group, a furyl-substituted phenylene group, a furyl-substituted 1-naphthylene group, a benzothienyl-substituted phenylene group, a benzothienyl-substituted 1-naphthylene group, a benzofuryl-substituted phenylene group, a benzofuryl-substituted 1-naphthylene group, and the like.

[0029] Examples of the heteroarylene group include a thienylene group, a furylene group, a benzothienylene group, a benzofurylene group, and the like.

[0030] Examples of the aryl-substituted heteroarylene group include a phenyl-substituted thienylene group, a phenyl-substituted furylene group, a phenyl-substituted benzothienylene group, a phenyl-substituted benzofurylene group, and the like.

[0031] Examples of the heteroaryl-substituted heteroarylene group include a thienyl-substituted thienylene group, a thienyl-substituted furylene group, a thienyl-substituted benzothienylene group, a thienyl-substituted benzofurylene group, a furyl-substituted thienylene group, a furyl-substituted furylene group, a furyl-substituted benzothienylene group, a furyl-substituted benzofurylene group, a benzothienyl-substituted thienylene group, a benzothienyl-substituted furylene group, a benzothienyl-substituted benzothienylene group, a benzothienyl-substituted benzofurylene group, a benzofuryl-substituted thienylene group, a benzofuryl-substituted furylene group, a benzofuryl-substituted benzothienylene group, a benzofuryl-substituted benzofurylene group, and the like.

[0032] R in the general formula (2) 8represents a substituent. Examples of the substituent include a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group, a halogen atom, a hydroxyl group, a nitro group, a carboxyl group, a cyano group, an alkoxy group, an aryloxy group, an acyl group, an acyloxy group, a carbamoyloxy group (such as an alkoxycarbonyloxy group), a primary amino group, an alkylamino group, an arylamino group, a dialkylamino group, a diarylamino group, an alkylarylamino group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, an arylthio group, a sulfo group, a sulfamoyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an imide group, an alkoxysulfonyl group, an aryloxysulfonyl group, a trialkylsilyl group, a trialkylsilyloxy group, a monovalent group derived from the compound represented by the general formula (1), and the like. These groups may be further substituted.

[0033] n8 in the general formula (2) represents an integer from 1 to the number of substitutable positions in Ar 1 Preferably, n8 is an integer from 1 to 3, and more preferably 1 or 2. When n8 is 2 or more, each R 8 may be the same or different. At least one R 8 is an electron-donating group. In this embodiment, the electron-donating group means a substituent having a Hammett σp value less than 0. Preferably, the electron-donating group has a Hammett σp value less than -0.1, and more preferably a Hammett σp value less than -0.2. The Hammett σp value is calculated by the following formula (I). Formula (I): σp = logKX - logKH

[0034] In formula (I), KH represents the ionization constant of benzoic acid in water at 25°C, and KX represents the ionization constant of benzoic acid having a substituent at the para position in water at 25°C. Examples of the electron-donating group include a hydroxyl group, an alkoxy group, a primary amino group, an alkylamino group, an arylamino group, a dialkylamino group, a diarylamino group, an alkylarylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, and a trialkylsilyl group.

[0035]

Chemical formula

[0036] In general formula (3), R 9 ~R 13 each independently represents a hydrogen atom or a substituent. Regarding the substituent as R 9 ~R 13 , it has the same meaning as the substituent of R 8 in general formula (2). Preferred examples of the substituent of R 9 ~R 12 include an alkyl group, an aryl group, and a heteroaryl group, and an alkyl group is more preferred. Preferred examples of the substituent as R 13 include an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group, and a monovalent group derived from the compound of general formula (1), and an alkenyl group and the monovalent group are more preferred. These alkyl groups, aryl groups, heteroaryl groups, alkenyl groups, and alkynyl groups may be further substituted. In a preferred embodiment of general formula (3), R 9 ~R 12 each independently represents a hydrogen atom or an alkyl group, and R 13 is a substituent. In a more preferred embodiment of general formula (3), R 9 ~R 12 independently represent hydrogen atoms, and R 13 is a substituted or unsubstituted alkenyl group. In general formula (3), p is an integer from 0 to 2.

[0037] R 1and R 2 、R 2 and R 3 、R 3 and R 4 、R 4 and R 5 、R 5 and R 6 、R 6 and R 7 may together represent a ring.

[0038] R 1 and R 2 、R 2 and R 3 、R 3 and R 4 、R 4 and R 5 、R 5 and R 6 、R 6 and R 7 are preferably together a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkenylene group, or a substituted or unsubstituted alkynylene group, more preferably a substituted or unsubstituted alkylene group or a substituted or unsubstituted alkenylene group, and still more preferably a substituted or unsubstituted alkylene group.

[0039] Examples of substituents that can be substituted in the alkylene group, alkenylene group, and alkynylene group include an alkyl group, an alkoxy group, an aryl group, and an aryloxy group. R 1 and R 2 、R 2 and R 3 、R 3 and R 4 、R 4 and R 5 、R 5 and R 6 、R 6 and R 7Combine to form a ring, preferably having 4 to 10 ring skeleton-forming atoms, more preferably having 5 to 8 ring skeleton-forming atoms, and still more preferably having 5 to 7 ring skeleton-forming atoms. Examples of the ring include a cyclopentane ring, a cyclohexane ring, and a cycloheptane ring. R 3 and R 4 or R 4 and R 5 Preferably form a ring together.

[0040] The compound represented by the general formula (1) includes the compound represented by the following general formula (4).

[0041]

Chemical formula

[0042] In the general formula (4), X 1 , X 2 , and R 2 ~R 6 Have the same meaning as in the general formula (1).

[0043] Ar 2 and Ar 3 Each independently represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group. The arylene group, aryl-substituted arylene group, heteroaryl-substituted arylene group, heteroarylene group, aryl-substituted heteroarylene group, and heteroaryl-substituted heteroarylene group have the same meaning as the examples in the general formula (2).

[0044] In this embodiment, Ar 2 and Ar 3is preferably independently a benzene structure, naphthalene structure, anthracene structure, fluorene structure, thiophene structure, furan structure, benzothiophene structure, benzofuran structure, phenyl-substituted thiophene structure, phenyl-substituted furan structure, phenyl-substituted benzothiophene structure or phenyl-substituted benzofuran structure, more preferably a benzene structure, naphthalene structure, anthracene structure or fluorene structure.

[0045] R 3 and R 4 、R 4 and R 5 may together form a ring, R 2 is Ar 2 may combine with to form a ring, R 6 is Ar 3 may combine with to form a ring. The formed ring is synonymous with the examples in general formula (1).

[0046] R 14 and R 15 each independently represents a substituent, and multiple R 14 may be the same or different, and at least one R 14 is an electron-donating group, and multiple R 15 may be the same or different, and at least one R 15 is an electron-donating group.

[0047] Regarding the substituents and electron-donating groups of R 14 and R 15 in general formula (4), the descriptions of the substituents exemplified as R 8 in general formula (2) and the electron-donating groups contained within those substituents can be referred to. R 14 and R 15As the electron-donating group, a substituted or unsubstituted diarylamino group is preferred. Examples of the diarylamino group include a diphenylamino group, a di(1-naphthyl)amino group, a di(2-naphthyl)amino group, and a 9-carbazolyl group. The diarylamino group may be substituted. Examples of the substituent of the substituted diarylamino group include an alkyl group, an alkoxy group, a thioalkoxy group, a trialkylsilyl group, an aryl group, an aryloxy group, and a diarylamino group (such as a 9-carbazolyl group). In this embodiment, R 14 and R 15 It is more preferable that at least one of them is a substituted or unsubstituted diarylamino group. Note that R 14 and R 15 may be bonded to the substituent of the arylene group or the substituent of the heteroarylene group.

[0048] n14 represents an integer from 1 to the number of substitutable positions in Ar 2 . When n14 is 2 or more, each R 14 may be the same or different. At least one R 14 is an electron-donating group. n15 represents an integer from 1 to the number of substitutable positions in Ar 3 . When n15 is 2 or more, each R 15 may be the same or different. At least one R 15 is an electron-donating group. n14 and n15 are preferably 1 to 3, more preferably 1 or 2.

[0049] The compound represented by the general formula (1) includes a compound represented by the following general formula (10).

[0050]

Chemical formula

[0051] In the general formula (10), X 1 , X 2 , and R 2 ~R6 is synonymous with the general formula (1).

[0052] Ar 2 and Ar 3 each independently represent an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group. The arylene group, aryl-substituted arylene group, heteroaryl-substituted arylene group, heteroarylene group, aryl-substituted heteroarylene group, and heteroaryl-substituted heteroarylene group are synonymous with the examples of the general formula (2).

[0053] In the present embodiment, Ar 2 and Ar 3 each independently are preferably a benzene structure, a naphthalene structure, an anthracene structure, a fluorene structure, a thiophene structure, a furan structure, a benzothiophene structure, a benzofuran structure, a phenyl-substituted thiophene structure, a phenyl-substituted furan structure, a phenyl-substituted benzothiophene structure, or a phenyl-substituted benzofuran structure.

[0054] R 3 and R 4 , R 4 and R 5 may together form a ring, R 2 may combine with Ar 2 to form a ring, and R 6 may combine with Ar 3 to form a ring. The formed ring is synonymous with the examples in the general formula (1).

[0055] n14 represents an integer from 1 to the number of substitutable positions in Ar 2 . When n14 is 2 or more, each R 14 may be the same or different. At least one R 14 is an electron-donating group. n15 represents an integer from 1 to the number of substitutable positions in Ar3, and when n15 is 2 or more, each R 15may be the same or different. At least one R 15 is an electron-donating group. n14 and n15 are preferably 1 to 3, more preferably 1 or 2.

[0056] R 14 and R 15 each independently represent a substituent containing an aryl group, and a plurality of R 14 may be the same or different, and at least one R 14 is an electron-donating group containing an aryl group, and a plurality of R 15 may be the same or different, and at least one R 15 is an electron-donating group containing an aryl group.

[0057] R in the general formula (10) 14 and R 15 are a substituent containing an aryl group and an electron-donating group containing an aryl group. Examples of the substituent containing an aryl group include an aryl group, a heteroaryl group, an aryloxy group, an arylamino group, a diarylamino group, an alkylarylamino group, an aryloxycarbonylamino group, an arylsulfonylamino group, an arylthio group, an arylsulfinyl group, an arylsulfonyl group, an aryloxycarbonyl group, an aryloxysulfonyl group. Among these, examples of the electron-donating group containing an aryl group are an aryl group, a heteroaryl group, an aryloxy group, an arylamino group, a diarylamino group, an alkylarylamino group, an arylthio group.

[0058] R 14 and R 15As the electron-donating group containing an aryl group, a substituted or unsubstituted diarylamino group is preferable. Examples of the diarylamino group include a diphenylamino group, a di(1-naphthyl)amino group, a di(2-naphthyl)amino group, and a 9-carbazolyl group. The diarylamino group may be substituted. Examples of the substituent of the substituted diarylamino group include an alkyl group, an alkoxy group, a thioalkoxy group, a trialkylsilyl group, an aryl group, an aryloxy group, and a diarylamino group (such as a 9-carbazolyl group). In this embodiment, R 14 and R 15 It is more preferable that at least one of them is a substituted or unsubstituted diarylamino group. Incidentally, R 14 and R 15 may be bonded to the substituent of the arylene group or the substituent of the heteroarylene group.

[0059] n14 represents an integer from 1 to the number of substitutable positions in Ar 2 . When n14 is 2 or more, each R 14 may be the same or different. At least one R 14 is an electron-donating group. n15 represents an integer from 1 to the number of substitutable positions in Ar3, and when n15 is 2 or more, each R 15 may be the same or different. At least one R 15 is an electron-donating group. n14 and n15 are preferably 1 to 3, and more preferably 1 or 2.

[0060] The compound represented by the general formula (1) includes a compound represented by the following general formula (5).

[0061]

Chemical formula

[0062] In the general formula (5), X 1 , X 2 , and R 2 ~R 6is synonymous with the general formula (1).

[0063] Ar 4 ~Ar 7 each independently represents a substituted or unsubstituted aryl group, and each Ar present in plurality 6 and each Ar 7 may be the same or different, and each Ar present in plurality 4 and each Ar 5 may be the same or different. Ar 4 ~Ar 7 is preferably a substituted or unsubstituted aryl group. Thereby, the conjugated system of the whole compound can be extended, and the absorption or emission wavelength can be made longer.

[0064] Ar 4 and Ar 5 , or Ar 6 and Ar 7 can be bonded to each other via a direct bond or a linking group such as a substituted or unsubstituted methylene group to form a ring. Examples of -N(Ar 4 )(Ar 5 ), and -N(Ar 6 )(Ar 7 ) include a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted di(1-naphthyl)amino group, a substituted or unsubstituted di(2-naphthyl)amino group, and a substituted or unsubstituted 9-carbazolyl group.

[0065] R 16 and R 17 each independently represents a substituent other than a substituted or unsubstituted diarylamino group, and R present in plurality 16 and R 17 may be the same or different. Regarding the substituents as R 16 and R 17 in the general formula (2), R 8Examples of the substituents may be referred to. Preferably, they are a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aryloxy group, and a substituted or unsubstituted heteroaryl group.

[0066] R 16 and R 2 、R 3 and R 4 、R 4 and R 5 、R 6 and R 17 may together form a ring. In this case, the ring is synonymous with the examples of the rings in general formula (1).

[0067] n16 and n18 each independently represent an integer of 0 or 1 or more, preferably 0 or 1. n17 and n19 each independently represent an integer of 1 or more, preferably 1 to 3. n16 + n17 is an integer of 1 to 5, and n18 + n19 is an integer of 1 to 5.

[0068] The compound represented by general formula (1) includes the compound represented by the following general formula (11).

[0069]

Chemical formula

[0070] In general formula (11), X 1 、X 2 、and R 2 ~R 6 are synonymous with the above general formula (1).

[0071] Ar 4 ~Ar 7 each independently represent a substituted or unsubstituted aryl group, and each Ar 6 and each Ar 7 may be the same or different, and each Ar 4 and each Ar 5 may be the same or different. Ar4 ~Ar 7 is preferably a substituted or unsubstituted aryl group. This can extend the conjugated system of the whole compound and achieve a longer wavelength of absorption or emission.

[0072] Ar 4 and Ar 5 or Ar 6 and Ar 7 may be bonded to each other directly or via a linking group such as a substituted or unsubstituted methylene group to form a ring. -N(Ar 4 )(Ar 5 ), and examples of -N(Ar 6 )(Ar 7 ) include a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted di(1-naphthyl)amino group, a substituted or unsubstituted di(2-naphthyl)amino group, and a substituted or unsubstituted 9-carbazolyl group.

[0073] R 16 and R 17 each independently represent a substituent other than a substituted or unsubstituted diarylamino group, and a plurality of R 16 and R 17 may be the same or different. For the substituents as R 16 and R 17 , the examples of the substituents of R 8 in the general formula (2) can be referred to. Preferably, they are a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aryloxy group, and a substituted or unsubstituted heteroaryl group.

[0074] R 16 and R 2 , R 3 and R 4 , R 4 and R 5 , R 6 and R 17 may combine together to form a ring. In this case, the ring is synonymous with the examples of the rings in the general formula (1).

[0075] n16 and n18 each independently represent an integer of 0 or more, preferably 0 or 1. n17 and n19 each independently represent an integer of 1 or more, preferably 1 to 3. n16 + n17 is an integer of 1 to 5, and n18 + n19 is an integer of 1 to 5.

[0076] The compound represented by the general formula (1) includes a compound represented by the following general formula (6).

[0077]

Chemical formula

[0078] In the general formula (6), X 1 , X 2 , and R 2 ~R 6 have the same meaning as in the general formula (1). X 1’ and X 2’ have the same meaning as X 1 and X 2 , and may be different from X 1 and X 2 .

[0079] R 2’ ~R 6’ each independently represent a hydrogen atom or a substituent. The substituents of R 2’ ~R 6’ have the same meaning as the substituents of R 2 ~R 6 in the general formula (1).

[0080] R 18 and R 19 each independently represent one of the following Group A.

[0081]

Chemical formula

[0082] In the formula, each R independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted aryl group having 6 to 10 carbon atoms, or a substituted or unsubstituted heteroaryl group.

[0083] Among the group A, the following substituents of group B are preferred.

[0084]

Chemical formula

[0085] Among the group A, the following substituents of group C are more preferred.

[0086]

Chemical formula

[0087] R 18 and R 2 , R 3 and R 4 , R 4 and R 5 , R 19 and R 2‘ , R 3’ and R 4‘ , and R 4’ and R 5‘ may together form a ring, R 6 may combine with A to form a ring, R 6’ may combine with A to form a ring. The ring is synonymous with the ring exemplified in the general formula (1).

[0088] A represents a linking group represented by the following general formula (7) or (9).

[0089]

Chemical formula

[0090] In general formula (7), n is an integer of 0 or 1 to 4, m is 0 or 1, A' represents an alkoxy group having 1 to 12 carbon atoms, and A'' represents a group represented by the following formula (8).

[0091] [Chemical formula]

[0092] In general formula (8), X 1’’ and X 2’’ are synonymous with X 1 and X 2 , and may be different from X 1 and X 2 in general formula (6).

[0093] R 2‘’ ~R 6‘’ each independently represents a hydrogen atom or a substituent, X 1’’ and X 2’’ represent a halogen atom, a halogenated alkyl group, or a halogenated aryl group, and R 20 represents one of the above Group A.

[0094] [Chemical formula]

[0095] In general formula (9), R 9 ~R 12 and p are synonymous with general formula (3).

[0096] In a preferred first embodiment of formula (6), A is an orthophenylene group represented by formula (7). Preferably, R 18 and R 19 are each independently one of the above Group B.

[0097] In a preferred second embodiment of formula (6), A is an orthophenylene group represented by formula (7), m is 0, n is 0, R 18 and R 19is independently one of the above-mentioned Group C respectively.

[0098] In a preferred third embodiment of formula (6), A is a metaphenylene group represented by formula (7). Preferably, R 18 and R 19 are independently one of the above-mentioned Group B respectively.

[0099] In a preferred fourth embodiment of formula (6), A is a metaphenylene group represented by formula (7), and R 18 and R 19 are independently one of the above-mentioned Group C respectively.

[0100] In a preferred fifth embodiment of formula (6), A is a metaphenylene group represented by formula (7), m is 0, and R 18 and R 19 are independently one of the above-mentioned Group C respectively. n is preferably 3.

[0101] In a preferred sixth embodiment of formula (6), A is a paraphenylene group represented by formula (7). Preferably, R 18 and R 19 are independently one of the above-mentioned Group B respectively.

[0102] In a preferred seventh embodiment of formula (6), A is a paraphenylene group represented by formula (7), and R 18 and R 19 are independently one of the above-mentioned Group C respectively.

[0103] In a preferred eighth embodiment of formula (6), A is a paraphenylene group represented by formula (7), m is 0, and R 18 and R 19 are independently one of the above-mentioned Group C respectively. A' is preferably an alkoxy group having 1 to 8 carbon atoms.

[0104] In a preferred ninth embodiment of formula (6), A is a linking group represented by formula (9). Preferably, R18 and R 19 is each independently one of the above-mentioned Group B.

[0105] In a preferred tenth embodiment of formula (6), A is a linking group represented by formula (9), and R 18 and R 19 is each independently one of the above-mentioned Group C.

[0106] In a preferred eleventh embodiment of formula (6), R 2 and R 2’ , R 3 and R 3’ , R 4 and R 4’ , R 5 and R 5’ , R 6 and R 6’ , and R 18 and R 19 are the same.

[0107] Specific examples of the compound represented by the general formula (1) of this embodiment are shown below. It is not limited to these specific examples.

[0108]

Chemical formula

[0109]

Chemical formula

[0110]

Chemical formula

[0111] When intending to form a film of an organic layer containing the compound represented by the general formula (1) by vapor deposition, for example, the molecular weight of the compound represented by the general formula (1) is preferably 1,500 or less, more preferably 1,200 or less, still more preferably 1,000 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 the general formula (1).

[0112] The compounds represented by the general formula (1) can be formed into a film by a coating method regardless of their molecular weights. Compounds with relatively large molecular weights can be formed into a film by a coating method.

[0113] As an application of this embodiment, a compound containing a plurality of structures each represented by the general formula (1) in the molecule can be used as a light-emitting material.

[0114] For example, it is conceivable to introduce a polymerizable group into the structure represented by the general formula (1) in advance and use the polymer obtained by polymerizing the polymerizable group as a light-emitting material. Specifically, R 1 ~R 7 It is conceivable to prepare a monomer having a polymerizable functional group in any of them, homopolymerize or copolymerize with another monomer to prepare a polymer containing repeating units, and use the polymer as a light-emitting material. Alternatively, it is conceivable to react a compound containing the structure represented by the general formula (1) to form a dimer or trimer, and use the dimer or trimer as a light-emitting material.

[0115] Examples of the polymer having a repeating unit containing the structure represented by the general formula (1) include polymers containing the structure represented by the following formula (31) or formula (32).

[0116]

Chemical formula

[0117]

Chemical formula

[0118] In formulas (31) and (32), n is an integer, Q represents a group containing the structure represented by formula (1), and L 1 and L 2 each represent a linking group. The linking group preferably has 0 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and even more preferably 2 to 10 carbon atoms. The linking group preferably has a structure represented by -X 11 -L 11 -. In the formula, X 11 represents an oxygen atom or a sulfur atom, preferably an oxygen atom, and L 11 represents a linking group, 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.

[0119] In general formulas (31) and (32), R 101 , R 102 , R 103 and R 104 each independently represent 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 even more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms or an unsubstituted alkoxy group having 1 to 3 carbon atoms.

[0120] L 1 and L 2 The linking group represented by can be bonded to any one of R 1 to R 7 of the structure of formula (1) constituting Q. Two or more linking groups can be bonded to one group represented by Q to form a crosslinked structure or a network structure.

[0121] Specific examples of the structure of the repeating unit include the structures represented by the following formulas (33) to (36).

[0122]

Chem.

[0123] A polymer having a repeating unit containing a structure represented by any of formulas (33) to (36), where n is an integer, and R in formula (1) 1 ~R 7 may be synthesized by introducing a hydroxyl group into any of them, reacting the hydroxyl group with the following compound as a linker to introduce a polymerizable group, and then polymerizing the polymerizable group.

[0124]

Chem.

[0125] A polymer containing a structure represented by formula (1) in the molecule may be a polymer containing only a repeating unit having a structure represented by formula (1), or may be a polymer further containing a repeating unit having another structure. The repeating unit having a structure represented by formula (1) contained in the polymer may be only one kind or two or more kinds. Examples of the repeating unit having no structure represented by formula (1) include repeating units derived from monomers used in ordinary copolymerization. Examples of the repeating unit include repeating units derived from monomers having an ethylenically unsaturated bond such as ethylene and styrene.

[0126] (Synthesis method of the compound represented by general formula (1)) The compound represented by general formula (1) can be synthesized by known reactions. For example, it can be synthesized as shown in the following Reaction Scheme 1 or 2.

[0127]

Chem.

[0128] In Reaction Schemes 1 and 2, X 1, X 2 , and R 1 ~R 7 is as defined by the general formula (1). R 2 , R 3 , R 5 and R 6 are hydrogen atoms, the aldehyde used in the second step is R 1 CHO or R 7 CHO. A mixture of R 1 CHO and R 7 CHO can be used. After the first step, purification may be performed and the second step may be proceeded, or after the first step, the second step may be proceeded without purification. In Reaction Formula 1, as reaction conditions, in the first step, the reaction temperature is preferably 0°C to room temperature and the reaction time is preferably 24 to 72 hours, and in the second step, the reaction temperature is preferably 60°C to reflux and the reaction time is preferably 4 to 24 hours. In Reaction Formula 2, in the first step, the reaction temperature is preferably room temperature and the reaction time is preferably 1 hour, and in the second step, the reaction temperature is preferably 60°C to reflux and the reaction time is preferably 4 to 24 hours. The reaction conditions may be determined as appropriate. For details of the reaction, the synthesis examples described later may be referred to.

[0129] (Organic electroluminescence element) The organic electroluminescence element of this embodiment contains a compound represented by the general formula (1) of this embodiment.

[0130] The compounds of this embodiment are useful as light-emitting materials for organic electroluminescence devices. Therefore, the compounds represented by the general formula (1) of this embodiment can be effectively used as light-emitting materials in the light-emitting layer of organic electroluminescence devices. The compounds represented by the general formula (1) include delayed fluorescence materials that emit delayed fluorescence. That is, this embodiment also provides an invention of a delayed phosphor having a structure represented by the general formula (1), an invention of using the compound represented by the general formula (1) as a delayed phosphor, and an invention of a method for emitting delayed fluorescence using the compound represented by the general formula (1). The organic electroluminescence device using the compound as a light-emitting material emits delayed fluorescence and has the characteristic of high luminous efficiency. The principle of that characteristic can be explained below.

[0131] In an organic electroluminescence device, carriers are injected from both the positive and negative electrodes into a light-emitting material to generate an excited light-emitting material and cause it to emit light. Usually, in the case of a carrier-injecting type organic electroluminescence device, out of the generated excitons, 25% are excited to the singlet excited state, and the remaining 75% are excited to the triplet excited state. Therefore, it is more energy-efficient to utilize phosphorescence, which is light emission from the triplet excited state. However, since the triplet excited state has a long lifetime, saturation of the excited state and energy deactivation due to interaction with excitons in the triplet excited state occur, and generally the quantum yield of phosphorescence is not high. On the other hand, a delayed phosphor emits fluorescence by reverse intersystem crossing to the singlet excited state through triplet-triplet annihilation or absorption of thermal energy after the energy has transitioned to the triplet excited state due to intersystem crossing or the like. In an organic electroluminescence device, among them, a thermally activated delayed fluorescence material due to absorption of thermal energy is considered to be particularly useful. When a delayed phosphor is used in an organic electroluminescence device, excitons in the singlet excited state emit fluorescence as usual. On the other hand, excitons in the triplet excited state absorb the heat generated by the device and undergo intersystem crossing to the singlet excited state to emit fluorescence. At this time, since it is light emission from the singlet excited state, it emits light at the same wavelength as fluorescence, but due to the reverse intersystem crossing from the triplet excited state to the singlet excited state, the lifetime of the generated light (luminescence lifetime) is longer than that of normal fluorescence and phosphorescence, and thus it is observed as fluorescence delayed more than these. This can be defined as delayed fluorescence. By using such a thermally activated exciton transfer mechanism, it is possible to raise the ratio of the compound in the singlet excited state, which is usually generated only 25%, to 25% or more by absorbing thermal energy after carrier injection. If a compound that emits strong fluorescence and delayed fluorescence even at a low temperature below 100 °C is used, intersystem crossing from the triplet excited state to the singlet excited state occurs sufficiently due to the heat of the device to emit delayed fluorescence, so that the luminous efficiency can be dramatically improved.

[0132] By using the compound represented by the general formula (1) of the present embodiment as a light-emitting material of the light-emitting layer, excellent organic light-emitting devices such as an organic photoluminescence device (organic PL device) and an organic electroluminescence device (organic EL device) can be provided. At this time, the compound represented by the general formula (1) of the present embodiment may have a function of assisting the light emission of other light-emitting materials contained in the light-emitting layer as a so-called assist dopant. That is, the compound represented by the general formula (1) of the present embodiment contained in the light-emitting layer may have the 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 other light-emitting materials contained in the light-emitting layer.

[0133] Further, the organic electroluminescence device has a structure containing at least an anode, a cathode, and an organic layer formed between the anode and the cathode. The organic layer includes at least a light-emitting layer, and may consist only of the light-emitting layer, or may have one or more organic layers in addition to the light-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 and transport layer having a hole injection function, and the electron transport layer may be an electron injection and transport layer having an electron injection function. A structural example of a specific organic electroluminescence device is shown in FIG. 19. In FIG. 19, 10 represents an organic electroluminescence device, 11 represents a substrate, 12 represents an anode, 13 represents a hole injection layer, 14 represents a hole transport layer, 15 represents a light-emitting layer, 16 represents an electron transport layer, and 17 represents a cathode.

[0134] Hereinafter, each member and each layer of the organic electroluminescence device will be described.

[0135] (Substrate) The organic electroluminescence device of this embodiment is preferably supported on a substrate. There are no particular restrictions on this substrate, and any substrate that has been conventionally used for organic electroluminescence devices may be used. For example, substrates made of glass, transparent plastic, quartz, silicon, etc. can be used.

[0136] (Anode) In the organic electroluminescence device, the anode is preferably formed from a metal, alloy, or electrically conductive compound each having a large work function (4 eV or more) and mixtures thereof as electrode materials. Specific examples of such electrode materials include metals such as Au, CuI, indium tin oxide (ITO), SnO2, ZnO and other conductive transparent materials. Also, materials such as IDIXO (In2O3-ZnO) that can form an amorphous transparent conductive film may be used. The anode may be formed into a thin film by methods such as vapor deposition or sputtering using these electrode materials, and a pattern of a desired shape may be formed by photolithography. Alternatively, when the pattern accuracy is not required so much (about 100 μm or more), a pattern may be formed through a mask of a desired shape during the vapor deposition or sputtering of the above electrode materials. Alternatively, when a material that can be applied, such as an organic conductive compound, is used, wet film formation methods such as printing or coating methods can also be used. When extracting light emission from this anode, it is desirable to make the transmittance greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / m2 or less. Further, the film thickness can usually be selected in the range of 10 to 1,000 nm, preferably 10 to 200 nm, although it depends on the material.

[0137] (Cathode) On the one hand, the cathode is preferably formed from an electrode material of a metal with a low work function (4 eV or less) (referred to as an electron injection metal), an alloy or an electrically conductive compound each with a low work function (4 eV or less), and a mixture thereof. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al2O3) mixture, indium, lithium / aluminum mixture, rare earth metals, and the like. Among these, from the viewpoints of electron injection and durability against oxidation and the like, a mixture of an electron injection metal and a second metal that is a metal with a larger and more stable work function value than this, for example, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al2O3) mixture, lithium / aluminum mixture, aluminum, etc. are preferable. The cathode can be fabricated by forming a thin film of these electrode materials by methods such as vapor deposition or sputtering. Also, the sheet resistance as the cathode is preferably several hundred Ω / m2 or less, and the film thickness can usually be selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. Incidentally, in order to transmit the emitted light, it is advantageous for the luminous intensity to be improved if either the anode or the cathode of the organic electroluminescence device is transparent or semi-transparent.

[0138] Also, by using the conductive transparent material mentioned in the description of the anode as the cathode, a transparent or semi-transparent cathode can be formed, and by applying this, an element in which both the anode and the cathode have permeability can be fabricated.

[0139] (Light-emitting layer) The light-emitting layer is a layer that emits light after excitons are generated by the recombination of holes and electrons injected from each of the anode and the cathode. The light-emitting material may be used alone in the light-emitting layer, but preferably includes a light-emitting material and a host material. As the light-emitting material, one or more selected from the group of compounds of the present embodiment represented by the general formula (1) can be used. In order for the organic electroluminescence device of the present embodiment to exhibit high luminous efficiency, it is important to confine singlet excitons and triplet excitons generated in the light-emitting material within the light-emitting material. Therefore, it is preferable to use a host material in addition to the light-emitting material in the light-emitting layer. As the host material, an organic compound having at least one of singlet excitation energy and triplet excitation energy higher than that of the light-emitting material of the present embodiment can be used. As a result, singlet excitons and triplet excitons generated in the light-emitting material of the present embodiment can be confined within the molecules of the light-emitting material of the present embodiment, and the luminous efficiency can be sufficiently extracted. However, even if singlet excitons and triplet excitons cannot be sufficiently confined, it may be possible to obtain high luminous efficiency. Therefore, any host material that can achieve high luminous efficiency can be used in the present embodiment without particular limitation. In the organic light-emitting device or organic electroluminescence device of the present embodiment, the light emission occurs from the light-emitting material of the present embodiment contained in the light-emitting layer. This light emission includes both fluorescence emission and delayed fluorescence emission. However, part or all of the light emission may be light emission from the host material.

[0140] When using a host material, the amount of the compound of the present embodiment, 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 preferably 50% by weight or less, more preferably 20% by weight or less, and even more preferably 10% by weight or less. As the host material in the light-emitting layer, an organic compound having hole-transporting ability, electron-transporting ability, preventing the wavelength of light emission from shifting to a longer wavelength, and having a high glass transition temperature is preferable.

[0141] (Injection layer) The injection layer is a layer provided between the electrode and the organic layer for reducing the driving voltage and improving the emission luminance. There are a hole injection layer and an electron injection layer, which 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.

[0142] (Blocking layer) The blocking layer is a layer that can prevent the diffusion of charges (electrons or holes) and / or excitons existing in the light-emitting layer outside the light-emitting layer. The electron blocking layer can be disposed between the light-emitting layer and the hole transport layer to prevent electrons from passing through the light-emitting layer toward the hole transport layer. Similarly, the hole blocking layer can be disposed between the light-emitting layer and the electron transport layer to prevent holes from passing through the light-emitting layer toward the electron transport layer. The blocking layer can also be used to prevent excitons from diffusing outside the light-emitting layer. That is, the electron blocking layer and the hole blocking layer can each also have the function of an exciton blocking layer. As used herein, the "electron blocking layer" or "exciton blocking layer" is used in the sense of including a layer having the functions of an electron blocking layer and an exciton blocking layer in one layer.

[0143] (Hole blocking layer) The hole blocking layer has the function of an electron transport layer in a broad sense. The hole blocking layer has the role of transporting electrons while preventing holes from reaching the electron transport layer, thereby improving the recombination probability of electrons and holes in the light-emitting layer. As the material of the hole blocking layer, the materials of the electron transport layer described later can be used as needed.

[0144] (Electron blocking layer) The electron blocking layer has the function of transporting holes in a broad sense. The electron blocking layer has the role of transporting holes while preventing electrons from reaching the hole transport layer, thereby improving the probability of recombination of electrons and holes in the light-emitting layer.

[0145] (Exciton blocking layer) The exciton blocking layer is a layer for preventing excitons generated by the recombination of holes and electrons in the light-emitting layer from diffusing into the charge transport layer. By inserting this layer, it becomes possible to efficiently confine excitons within the light-emitting layer, and the light-emitting efficiency of the device can be improved. The exciton blocking layer can be inserted on either the anode side or the cathode side adjacent to the light-emitting layer, and it is also possible to insert both simultaneously. That is, when the exciton blocking layer is on the anode side, this layer can be inserted adjacent to the light-emitting layer between the hole transport layer and the light-emitting layer. When inserted on the cathode side, this layer can be inserted adjacent to the light-emitting layer between the light-emitting layer and the cathode. Also, between the anode and the exciton blocking layer adjacent to the anode side of the light-emitting layer, a hole injection layer, an electron blocking layer, etc. can be provided. Between the cathode and the exciton blocking layer adjacent to the cathode side of the light-emitting layer, an electron injection layer, an electron transport layer, a hole blocking layer, etc. can be provided. When arranging the blocking layer, at least one of the singlet exciton energy and the triplet exciton energy of the material used as the blocking layer is preferably higher than the singlet exciton energy and the triplet exciton energy of the light-emitting layer, respectively.

[0146] (Hole transport layer) The hole transport layer is composed of a hole transport material having a function of transporting holes, and the hole transport layer can be provided as a single layer or multiple layers.

[0147] As the hole transport material, it should have either the function of hole injection or transport or the function of electron barrier, and it can be either organic or inorganic. Known hole transport materials that can be used include, for example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, especially thiophene oligomers, etc. However, it is preferable to use porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds, and it is more preferable to use aromatic tertiary amine compounds.

[0148] (Electron transport layer) The electron transport layer is made of a material having the function of transporting electrons, and the electron transport layer can be provided as a single layer or multiple layers.

[0149] As the electron transport material (which may also serve as a hole blocking material), it only needs to have the function of transmitting electrons injected from the cathode to the light-emitting layer. Examples of electron transport layers that can be used include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimide, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, etc. Furthermore, in the above oxadiazole derivatives, thiadiazole derivatives in which the oxygen atom of the oxadiazole ring is substituted 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, polymer materials in which these materials are introduced into the polymer chain or these materials are used as the main chain of the polymer can also be used.

[0150] When manufacturing an organic electroluminescent device, the compound represented by the 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 the general formula (1) used in the light-emitting layer and the compound represented by the general formula (1) used in layers other than the light-emitting layer may be the same or different. For example, the compound represented by the general formula (1) may also be used in the above-mentioned injection layer, blocking layer, hole blocking layer, electron blocking layer, exciton blocking layer, hole transport layer, electron transport layer, etc. The film formation method of these layers is not particularly limited, and they may be formed by either a dry process or a wet process.

[0151] Hereinafter, preferred materials that can be used in the organic electroluminescent device will be specifically exemplified. However, the materials that can be used in the present embodiment should not be construed as being limited to the following exemplified compounds. Also, even if a compound is exemplified as a material having a specific function, it can also be diverted as a material having other functions. In the structural formula of the exemplified compound, R, R2 to R7 each independently represent a hydrogen atom or a substituent, and n represents an integer of 3 to 5.

[0152] Preferred examples of compounds that can be used as the host material of the light-emitting layer are shown below.

[0153]

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0154] Preferred examples of compounds that can be used as the hole injection material are shown below.

[0155]

Chemical formula

[0156] Preferred examples of compounds that can be used as hole transport materials are shown below.

[0157] [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula]

[0158] Preferred examples of compounds that can be used as electron blocking materials are shown below.

[0159] [Chemical formula]

[0160] Preferred examples of compounds that can be used as hole blocking materials are shown below.

[0161] [Chemical formula] [Chemical formula]

[0162] Preferred examples of compounds that can be used as electron transport materials are shown below.

[0163] [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula]

[0164] Preferred examples of compounds that can be used as electron injection materials are shown below.

[0165] [Chemical formula]

[0166] Examples of preferred compounds as additives are shown below. For example, the compound can be added as a stabilizing material.

[0167] [Chemical formula]

[0168] The organic electroluminescence device fabricated by the above method emits light by applying an electric field between the anode and the cathode of the obtained device. At this time, if the light emission is due to the singlet excitation energy, light of a wavelength corresponding to that energy level is confirmed as fluorescence emission and delayed fluorescence emission. Also, if the light emission is due to the triplet excitation energy, light of a wavelength corresponding to that energy level is confirmed as phosphorescence. Since normal fluorescence has a shorter fluorescence lifetime than delayed fluorescence emission, the emission lifetime can be distinguished between fluorescence and delayed fluorescence.

[0169] On the other hand, regarding phosphorescence, in ordinary organic compounds such as the compounds of this embodiment, the triplet excitation energy is unstable and is converted into heat or the like, and the lifetime is short and it is deactivated immediately, so that it can hardly be observed at room temperature. In order to measure the triplet excitation energy of ordinary organic compounds, it can be measured by observing light emission under cryogenic conditions.

[0170] The organic electroluminescence device of the present embodiment can be applied to any of a single device, a device having a structure arranged in an array, and a structure in which an anode and a cathode are arranged in an X-Y matrix.

[0171] According to the present embodiment, by incorporating a compound represented by the general formula (1) into the light-emitting layer, an organic light-emitting device with greatly improved light-emitting efficiency in the NIR region can be obtained. Organic light-emitting devices such as the organic electroluminescence device of the present embodiment can be further applied to various uses. For example, it is possible to manufacture an organic electroluminescence display device using the organic electroluminescence device of the present embodiment. For details, reference can be made to "Organic EL Display" (Ohmsha, Ltd.) co-authored by Shizushi Tokito, Chihaya Adachi, and Hideyuki Murata. In particular, the organic electroluminescence device of the present embodiment can also be applied to bioimaging, medical cameras, sensors, security cameras, night vision displays, and information protection displays.

[0172] The compounds represented by the general formula (1) exhibit high fluorescence quantum yields and have improved NIR light-emitting characteristics. They can be used both in solution, particularly in organic solvents, and in the solid state.

[0173] The compounds represented by the general formulas (1), (4), (5), and (6) are useful as sensors for volatile acids / bases, in photodynamic therapy, in the diagnosis of Alzheimer's disease, in seranostics, as optical sensors for anaerobic environments, in displays and telecommunication technologies, particularly as electron donors in solar cells, and as light emitters in organic semiconductor lasers, particularly in cell imaging in bioimaging. They can represent fluorescent reporters of human β-amyloid peptides produced in neural tissues and blood during the progression of Alzheimer's disease, and thus can be used for the diagnosis of Alzheimer's disease.

[0174] This embodiment also provides an organic semiconductor laser containing a compound represented by the general formula (1). The compound of the general formula (1) is useful as a material used in the light-emitting layer (optical amplification layer) of an organic semiconductor laser.

[0175] The light-emitting layer may contain two or more compounds of the general formula (1), but preferably contains only one compound of the general formula (1). The light-emitting layer may contain a host material. Preferred host materials have sufficient spectral overlap between their fluorescence spectra and the absorption spectra of the compounds of the general formula (1) contained in the light-emitting layer, so that effective Förster-type energy transfer from the host material to the compounds of the general formula (1) can occur. Examples of preferred host materials are the same as those exemplified by chemical formulas as the "preferred examples of compounds that can be used as host materials for the light-emitting layer" described above. The concentration of the compound of the general formula (1) in the light-emitting layer is preferably contained in an amount of 0.1% by mass or more, more preferably 1% by mass or more, and still more preferably 3% by mass or more in 100% by mass of the light-emitting layer. The upper limit value of the concentration of the compound of the general formula (1) is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 10% by mass or less. The lower limit and the upper limit can be arbitrarily combined.

[0176] The organic semiconductor laser of this embodiment has an optical resonator structure. The optical resonator structure can be a one-dimensional resonator structure or a two-dimensional resonator structure. Examples of the two-dimensional resonator structure include a circulator resonator structure, a whispering gallery type optical resonator structure, etc. Distributed feedback (DFB) structures and distributed Bragg reflector (DBR) structures can also be used. For DFB, a mixed-order DFB grating structure is preferably used. That is, a mixed structure with a DFB grating structure different in terms of the order with respect to the laser emission wavelength can preferably be used.

[0177] As a specific example, an optical resonator structure including a secondary Bragg scattering region surrounded by a primary Bragg scattering region and a mixed structure in which the secondary Bragg scattering region and the primary scattering region are alternately formed can be mentioned. For details of the preferred optical resonator structure, the specific examples described later can be referred to. As the optical resonator structure, the organic semiconductor laser may further include an optical resonator structure on the outside. For example, the optical resonator structure is preferably formed on a glass substrate. Examples of the material constituting the optical resonator structure include insulating materials such as SiO2. For example, when a grating structure is formed, the depth of the grating is preferably 75 nm or less, more preferably selected from the range of 10 to 75 nm. The depth may be, for example, 40 nm or more, or less than 40 nm. The light-emitting layer (optical amplification layer) containing the compound of the general formula (1) can be directly formed on the optical resonator structure.

[0178] The organic semiconductor laser is preferably encapsulated with sapphire or other materials in order to lower the oscillation threshold and optimize heat dissipation under strong optical pumping. An intermediate layer can be formed between the sapphire lid and the light-emitting layer. For example, an amorphous fluorinated polymer such as CYTOP (registered trademark) is preferably used for the intermediate layer.

[0179] As described above, the embodiments of the present invention have been described, but these are examples of the present invention, and various configurations other than the above can be adopted as long as the effects of the present invention are not impaired.

Example

[0180] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. (Synthesis Example 1) Synthesis of Compound 2

Chemical formula

[0181] 4-[N,N-Bis(bromophenyl)amino]benzaldehyde (2.53 g, 5.87 mmol), 4-isopropoxyphenylboronic acid (2.74 g, 15.2 mmol) and potassium carbonate (4.19 g, 30.3 mmol) were added to a mixed solution of toluene (90 mL) and water (30 mL), and tetrakis(triphenylphosphine)palladium(0) (0.270 g, 0.234 mmol) was added thereto. The mixture was heated under reflux for 2.5 hours under a nitrogen atmosphere. Thereafter, the reaction solution was diluted with toluene and washed with saturated brine. The aqueous layer was extracted twice with dichloromethane, and the combined organic layers were dried over magnesium sulfate, filtered and concentrated. The residue was purified by silica gel column (chloroform - dichloromethane) to obtain Intermediate 1 (2.90 g, 91%) represented by the following formula as a yellow solid. [Chemical formula]

[0182] mp 60 °C; 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 1.36 (s, 6H), 1.38 (s, 6H), 4.55 - 4.65 (m, 2H), 6.96 (d, 4H, J = 8.8 Hz), 7.11 (d, 2H, J = 8.8 Hz), 7.24 (d, 4H, J = 8.5 Hz), 7.48 - 7.56 (m, 8H), 7.71 (d, 2H, J = 8.8 Hz).

[0183] A suspension of potassium trifluoro(trifluoromethyl)borate (0.368 g, 2.09 mmol) cooled to 0 °C in acetonitrile (10 mL) was added dropwise with trimethylsilyl trifluoromethanesulfonate (0.38 mL, 2.10 mmol), and stirred at 0 °C for 0.5 h under a nitrogen atmosphere. Then, 3-phenyl-2,4-pentanedione (0.185 g, 1.05 mmol) was added to the reaction solution, the temperature was raised to room temperature, and stirred for three nights under a nitrogen atmosphere. Then, a solution of 4-[bis(4'-isopropoxybiphenyl-4-yl)amino]benzaldehyde (Intermediate 1) (1.16 g, 2.14 mmol) and tributyl borate (0.68 mL, 2.54 mmol) in ethyl acetate (30 mL) was added to the reaction solution, and stirred at 40 °C for 0.5 h under a nitrogen atmosphere. Morpholine (0.223 mL, 2.56 mmol) was added to the reaction solution, and stirred at 70 °C for 7 h under a nitrogen atmosphere. Further, morpholine (0.045 mL, 0.52 mmol) was added to the reaction solution, and stirred at 70 °C for 1.5 h under a nitrogen atmosphere. After the reaction solution was returned to room temperature, it was concentrated and the residue was purified by a silica gel column (dichloromethane - toluene), and the obtained solid was suspended and washed with hexane to obtain 0.489 g (35%) of the compound 2 represented by the above formula as a dark blue solid.

[0184] mp 264 °C; 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 1.36 (s, 12H), 1.38 (s, 12H), 4.54 - 4.65 (m, 4H), 6.32 (d, 2H, J = 15.1 Hz), 6.92 - 7.00 (m, 12H), 7.18 (d, 8H, J = 8.5 Hz), 7.27 - 7.32 (m, 6H), 7.42 - 7.53 (m, 19H), 7.98 (d, 2H, J = 15.1 Hz); LRMS (FD): m / z calcd for C86H77BF4N2O6+: 1320.6 [M]+; found 1320.6.

[0185] (Synthesis Example 2) Synthesis of Compound 1

Chemical Formula

[0186] As raw materials and reaction reagents, potassium trifluoro(trifluoromethyl)borate (0.493 g, 2.80 mmol), trimethylsilyl trifluoromethanesulfonate (0.52 mL, 2.88 mmol), 3-phenyl-2,4-pentanedione (0.269 g, 1.53 mmol), 4-(N,N-diphenylamino)benzaldehyde (0.809 g, 2.96 mmol), tributyl borate (0.94 mL, 3.51 mmol) and morpholine (0.372 mL, 4.26 mmol) were used. By the same method as in the synthesis of Compound 2 in Synthesis Example 1, Compound 1 (0.466 g, 39%) represented by the above formula as a dark blue solid was obtained.

[0187] mp 271 °C; 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 6.30 (d, 2H, J = 15.1 Hz), 6.88 (d, 4H, J = 8.8 Hz), 7.09 - 7.16 (m, 12H), 7.21 - 7.25 (m, 4H), 7.27 - 7.33 (m, 10H), 7.41 - 7.48 (m, 3H), 7.96 (d, 2H, J = 15.4 Hz); LRMS (FD): m / z calcd for C50H37BF4N2O2+: 784.3 [M]+; found 784.3.

[0188] (Synthesis Example 3) Synthesis of Compound 3

Chemical formula

[0189] As raw materials and reaction reagents, potassium trifluoro(pentafluoroethyl)borate (0.470 g, 2.08 mmol), trimethylsilyl trifluoromethanesulfonate (0.38 mL, 2.10 mmol), 3-phenyl-2,4-pentanedione (0.190 g, 1.08 mmol), 4-(N,N-diphenylamino)benzaldehyde (0.593 g, 2.17 mmol), tributyl borate (0.68 mL, 2.54 mmol) and morpholine (0.266 mL, 3.06 mmol) were used, and in the same manner as in the synthesis of Compound 2 in Synthesis Example 1, 0.693 g (77%) of Compound 3 represented by the above formula as a dark blue solid was obtained.

[0190] mp 242 °C; 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 6.30 (d, 2H, J = 15.1 Hz), 6.88 (d, 4H, J = 8.8 Hz), 7.09 - 7.16 (m, 12H), 7.23 (d, 4H, J = 9.0 Hz), 7.26 - 7.33 (m, 10H), 7.41 - 7.48 (m, 3H), 7.93 (d, 2H, J = 15.1 Hz); LRMS (FD): m / z calcd for C51H37BF6N2O2+: 834.3 [M]+; found 834.3.

[0191] (Synthesis Example 4) Synthesis of Compound 4

Chemical formula

[0192] To a dichloromethane (10 mL) solution of 3-phenyl-2,4-pentanedione (0.2439 g, 1.38 mmol), fluorobis(pentafluorophenyl)borane diethyl ether complex (2.3356 g, 5.332 mmol) was added, and the mixture was stirred at room temperature for two nights under a nitrogen atmosphere. The reaction solution was concentrated and the residue was passed through a silica gel column (hexane - ethyl acetate) to obtain Intermediate 2 represented by the following formula as a crude product.

Chemical formula

[0193] To a solution of Intermediate 2 (4 mL) in ethyl acetate, a solution of 4-(N,N-diphenylamino)benzaldehyde (0.692 g, 2.53 mmol) and tributyl borate (0.8 mL, 2.99 mmol) in ethyl acetate (25 mL) was added. Then, morpholine (0.105 mL, 1.2 mmol) was added to the reaction solution, and the mixture was heated to reflux for 4.5 hours under a nitrogen atmosphere. After the reaction solution was returned to room temperature, it was concentrated, and the residue was purified by silica gel column (dichloromethane). The obtained solid was suspended and washed with methanol to obtain 1.08 g (87%) of the compound 4 represented by the above formula as a dark blue solid.

[0194] mp 277 °C 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 6.36 (d, 2H, J = 15.2 Hz), 7.10 - 7.14 (m, 12H), 7.20 - 7.22 (m, 2H), 7.25 - 7.31 (m, 10H), 7.41 - 7.43 (m, 3H), 7.96 (d, 2H, J = 15.2 Hz); LRMS (FD): m / z calcd for C61H37BF10N2O2+: 1030.3 [M]+; found 1030.3.

[0195] (Synthesis Example 5) Synthesis of Compound 5

Chemical formula

[0196] Using 4-[N,N-bis(bromophenyl)amino]benzaldehyde (3.06 g, 7.11 mmol), 4-trimethylsilylphenylboronic acid (3.52 g, 18.1 mmol), tetrakis(triphenylphosphine)palladium(0) (0.333 g, 0.288 mmol), and potassium carbonate (5.65 g, 40.9 mmol) as raw materials and reaction reagents, Intermediate 3 represented by the following formula as a yellow solid (3.77 g, 93%) was obtained in the same manner as the synthesis of Intermediate 1 in Synthesis Example 1.

Chemical formula

[0197] mp 92 °C; 1 H-NMR (270 MHz, CDCl3) δ (ppm) 0.31 (s, 18H), 7.15 (d, 2H, J = 8.6 Hz), 7.23 - 7.30 (m, 6H), 7.55 - 7.64 (m, 12H) 7.73 (d, 2H, J = 8.9 Hz), 9.84 (s, 1H).

[0198] Using potassium trifluoro(trifluoromethyl)borate (0.338 g, 1.92 mmol), trimethylsilyl trifluoromethanesulfonate (0.36 mL, 1.99 mmol), 3-phenyl-2,4-pentanedione (0.174 g, 0.987 mmol), Intermediate 3 (1.13 g, 1.99 mmol), tributyl borate (0.64 mL, 2.39 mmol) and morpholine (0.21 mL, 2.41 mmol) as raw materials and reaction reagents, in the same manner as the synthesis of Compound 2 in Synthesis Example 1, a compound 5 (0.398 g, 29%) represented by the above formula as a dark blue solid was obtained.

[0199] mp 207 °C; 1 H-NMR (400 MHz, CDCl3) δ (ppm) 0.30 (s, 36H) 6.34 (d, 2H, J = 15.4 Hz), 7.01 (d, 4H, J = 9.3 Hz), 7.22 (dd, 12H, J = 4.1, 9.3 Hz), 7.28 - 7.32 (m, 6H), 7.43 - 7.49 (m, 3H), 7.52 - 7.62 (m, 3H), 7.99 (d, 2H, J = 15.4 Hz); LRMS (FD): m / z calcd for C 86 H 85 BF4N2O2Si4 + : 1377.6 [M] + ; found 1377.6.

[0200] (Synthesis Example 6) Synthesis of Compound 6

Chemical Structure

[0201] As raw materials and reaction reagents, potassium trifluoro(trifluoromethyl)borate (0.539 g, 3.15 mmol), trimethylsilyl trifluoromethanesulfonate (0.58 mL, 3.20 mmol), 3-phenyl-2,4-pentanedione (0.282 g, 1.60 mmol), 4-[bis(4-(tert-butyl)phenyl)amino]benzaldehyde (1.23 g, 3.19 mmol), tributyl borate (1.03 mL, 3.85 mmol) and morpholine (0.746 mL, 8.55 mmol) were used. In the same manner as in the synthesis of Compound 2 of Synthesis Example 1, a dark blue solid compound 6 (0.649 g, 40%) represented by the above formula was obtained.

[0202] mp Decomp.; 1 H-NMR (400 MHz, CDCl3) δ (ppm) 1.31 (s, 36H), 6.26 (d, 2H, J = 15.4 Hz), 6.83 (d, 4H, J = 9.0 Hz), 7.02 - 7.07 (m, 8H), 7.21 (d, 4H, J = 9.0 Hz), 7.26 - 7.33 (m, 10H), 7.39 - 7.45 (m, 3H), 7.94 (d, 2H, J = 15.4 Hz); LRMS (FD): m / z calcd for C 66 H 69 BF4N2O2 + : 1008.5 [M] + ; found 1008.6.

[0203] (Synthesis Example 7) Synthesis of Compound 7

Chemical formula

[0204] As raw materials and reaction reagents, potassium trifluoro(trifluoromethyl)borate (0.367 g, 2.09 mmol), trimethylsilyl trifluoromethanesulfonate (0.4 mL, 2.21 mmol), methyl 4-(3'-acetylacetonate)benzoate (0.261 g, 1.11 mmol), Intermediate 1 (1.22 g, 2.25 mmol), tributyl borate (0.72 mL, 2.69 mmol) and morpholine (0.232 mL, 2.67 mmol) were used, and in the same manner as in the synthesis of Compound 2 in Synthesis Example 1, a compound 7 (0.439 g, 29%) represented by the above formula as a dark blue solid was obtained.

[0205] mp 273 °C; 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 1.36 (s, 12H), 1.38 (s, 12H), 3.94 (s, 3H), 4.53 - 4.62 (m, 4H), 6.24 (d, 2H, J = 15.1 Hz), 6.92 - 7.00 (m, 12H), 7.19 (d, 8H, J = 8.5 Hz), 7.23 - 7.29 (m, 4H), 7.41 (d, 2H, J = 8.3 Hz), 7.46 - 7.52 (m, 16H), 8.00 (d, 2H, J = 15.1 Hz), 8.14 (d, 2H, J = 8.3 Hz); LRMS (FD): m / z calcd for C 88 H 79 BF4N2O8 + : 1378.6 [M] + ; found 1378.6.

[0206] (Synthesis Example 8) Synthesis of Compound 8

Chemical formula

[0207] As raw materials and reaction reagents, potassium trifluoro(trifluoromethyl)borate (0.522 g, 2.97 mmol), trimethylsilyl trifluoromethanesulfonate (0.54 mL, 2.99 mmol), 3-phenyl-2,4-pentanedione (0.261 g, 1.48 mmol), 5-[4-(bis(4-tert-butylphenyl)amino)phenyl]thiophene-2-carbaldehyde (1.45 g, 3.10 mmol), tributyl borate (0.99 mL, 3.70 mmol) and morpholine (0.372 mL, 4.28 mmol) were used, and in the same manner as in the synthesis of Compound 2 in Synthesis Example 1, 0.606 g (35%) of Compound 8 represented by the above formula as a dark blue solid was obtained. mp 209 °C;

[0208] 1 1H-NMR (400 MHz, CDCl3) δ (ppm) 1.32 (s, 36H), 6.16 (d, 2H, J = 14.9 Hz), 6.97 (d, 4H, J = 8.8 Hz), 7.02 - 7.06 (m, 8H), 7.17 (d, 2H, J = 4.1 Hz), 7.26 - 7.33 (m, 12H), 7.39 (dd, 4H, J = 4.9, 8.8 Hz), 7.48 - 7.53 (m, 3H), 8.09 (d, 2H, J = 15.1 Hz); LRMS (FD): m / z calcd for C 74 H 73 BF4N2O2S2 + : 1172.5 [M] + ; found 1172.5.

[0209] (Synthesis Example 9) Synthesis of Compound 9

Chemical Formula

[0210] As raw materials and reaction reagents, potassium trifluoro(trifluoromethyl)borate (0.600 g, 3.41 mmol), trimethylsilyl trifluoromethanesulfonate (0.62 mL, 3.43 mmol), 3-phenyl-2,4-pentanedione (0.315 g, 1.79 mmol), 5-(diphenylamino)thiophene-2-carbaldehyde (0.996 g, 3.57 mmol), tributyl borate (1.14 mL, 4.26 mmol) and morpholine (0.43 mL, 4.94 mmol) were used, and in the same manner as in the synthesis of Compound 2 in Synthesis Example 1, 0.573 g (40%) of Compound 9 represented by the above formula as a dark blue solid was obtained. mp 287 °C; 1 H-NMR (400 MHz, CDCl3) δ (ppm) 5.72 (d, 2H, J = 14.9 Hz), 6.34 (d, 2H, J = 4.4 Hz), 7.12 (d, 2H, J = 4.1 Hz), 7.15 - 7.22 (m, 14H), 7.30 - 7.39 (m, 11H), 7.41 - 7.48 (m, 3H), 7.97 (d, 2H, J = 14.6 Hz); LRMS (FD): m / z calcd for C 46 H 33 BF4N2O2S2 + : 796.2 [M] + ; found 796.2.

[0211] (Synthesis Example 10) Synthesis of Compound 10

Chemical formula

[0212] In a 50 mL flask, a mixture of ethyl diacetoacetate (228 μL, 1.463 mmol, 1 equiv) and BF3·Et2O (199 μL, 1.609 mmol, 1.1 equiv) in 3 mL of ethyl acetate was heated at 50 - 60 °C in air for 30 minutes. 4-(N,N-Diphenylamino)-benzaldehyde (1 g, 3.658 mmol, 2.5 equiv) and B(n-OBu)3 (0.987 mL, 3.658 mmol, 2.5 equiv) were dissolved in 12 mL of ethyl acetate, and then the solution was poured into the first mixture. The reaction was continued at 50 - 60 °C for an additional 30 minutes. The first portion of BuNH2 (58 μL, 0.585 mmol, 0.4 equiv) was added dropwise to the reaction. After heating for 6 hours, the second portion of BuNH2 (29 μL, 0.293 mmol, 0.2 equiv) was added, and the reaction was continued to be heated at 50 - 60 °C overnight. All the solvents were evaporated. Flash column chromatography (silica, CH2Cl2) gave a crude product contaminated with a small amount of ligand and aldehyde. Further purification was carried out by precipitation twice in CH2Cl2 / petroleum ether to give the compound 10 represented by the above formula as a dark green powder (730 mg, 68% yield).

[0213] 1 1H-NMR (400 MHz, CDCl3, ppm): δ 8.10 (d, 1J = 15.1 Hz, 2H), 7.45 (d, 1J = 8.8 Hz, 4H), 7.34 (m, 8H), 7.17 (m, 14H), 6.97 (d, 1J = 8.7 Hz, 4H), 4.40 (m, 2H), 1.42 (t, 1J = 7.4 Hz, 3H). HRMS (ESI+) [M + Na]+ calcd for C46H37N2O4BF2Na+ m / z = 753.2712, found m / z = 753.2716.

[0214] (Absorption and Emission) (Example 1) Solution Compound 1 was dissolved in the following solvents to prepare solutions (concentration: 10-5 mol / L). Dichloromethane (DCM) Toluene (Tol)

[0215] When this solution was irradiated with light at room temperature, luminescence was observed. Figures 1 and 2 show the normalized electronic absorption and luminescence (PL) spectra of the DCM solution and Tol solution of Compound 1, respectively. The absorption wavelength λabs (nm), luminescence (PL) wavelength λem (nm), Stokes shift ΔνST (cm-1), and quantum yield Φf (%) are shown in Table 1. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer LAMBMA950 (manufactured by PerkinElmer Japan Co., Ltd.), the luminescence (PL) spectrum was measured using a spectrofluorophotometer FP-8600 (manufactured by JASCO Corporation), and the quantum yield was measured using an absolute PL quantum yield measurement device (manufactured by Hamamatsu Photonics K.K.).

[0216]

Table 1

[0217] Similarly, solutions of Compounds 2, 3, and 5-9 were prepared, and absorption and luminescence were observed. The absorption wavelength λabs (nm), luminescence (PL) wavelength λem (nm), Stokes shift ΔνST (cm-1), and quantum yield Φf (%) of the solutions of Compounds 2, 3, and 5-9 are shown in Tables 2-8, respectively.

[0218]

Table 2

[0219]

Table 3

[0220]

Table 4

[0221]

Table 5

[0222]

Table 6

[0223]

Table 7

[0224]

Table 8

[0225] In the solution spectra of Compounds 1 to 3 and 5 to 9, the peak wavelength tends to shift to a longer wavelength in DCM, a higher polarity solvent, than in Tol, a lower polarity solvent, and a bathochromic effect due to the polarity of the solvent was observed. This result indicates that this curcuminoid compound has charge transfer properties. This behavior is related to the strong electron-withdrawing property of the central halogen and boron alkyl halide moieties and the strong electron-donating property of the triphenylamine moieties at both ends.

[0226] (Comparative Example 1) For Compound 10, a solution was prepared in the same manner as in Example 1. The normalized electronic absorption and emission (PL) spectra of the DCM solution and Tol solution are shown in FIGS. 3 and 4. Also, the absorption wavelength λabs (nm), emission (PL) wavelength λem (nm), Stokes shift ΔνST (cm−1), and quantum yield Φf (%) are shown in Table 9.

[0227]

Table 9

[0228] A bathochromic effect due to the solvent was also observed for Compound 10, indicating that it has charge transfer properties, similar to Compounds 1 to 3 and 5 to 9. Compared with Compounds 1 to 3 and 5 to 9, the absorption and emission (PL) wavelengths of Compound 10 in toluene or dichloromethane solution are shorter. This is presumably because the halogenated alkyl group bonded to boron in Compounds 1 to 3 and 5 to 9 has a stronger electron-withdrawing property than fluorine.

[0229] (Example 2) Thin Film 82 μL of a chloroform solution of Compound 1 at 5 mg / mL and 338 μL of a chloroform solution of 4,4'-bis(N-carbazolyl)-1,10-biphenyl (CBP) at 35 mg / mL were mixed, and the resulting solution was spin-coated onto a pre-cleaned quartz substrate to form a thin film with a thickness of 200 nm. The concentration of Compound 1 in the thin film was 3 wt%. When this thin film was irradiated with light at room temperature, luminescence was observed. Figure 5 shows the normalized electronic absorption and luminescence (PL) spectra of the thin film of Compound 1. The absorption wavelength λabs (nm), the luminescence (PL) wavelength λem (nm), and the photoluminescence quantum yield PLQY (Φf) (%) are shown in Table 10. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer LAMBMA950 (manufactured by PerkinElmer Japan Co., Ltd.), the luminescence (PL) spectrum was measured using a spectrofluorometer FP-8600 (manufactured by JASCO Corporation), and the quantum yield was measured using an absolute PL quantum yield measuring device (manufactured by Hamamatsu Photonics K.K.).

[0230] [Table 10]

[0231] Similarly, measurements of Compounds 2 to 9 were performed. The results are summarized in Table 11.

[0232] [Table 11]

[0233] The absorption peak wavelengths of Compounds 1 to 9 correspond to transitions involving charge transfer from the ground state (S0) to the first singlet excited state (S1). When Compounds 1 to 9 were excited at 340 nm, the emission (PL) peak wavelengths were 713 nm, 748 nm, 727 nm, 716 nm, 754 nm, 750 nm, 773 nm, 797 nm, and 770 nm, respectively, and the PLQYs were 55%, 23%, 53%, 59%, 42%, 37%, 11%, 8%, and 7%, respectively. Compared with Compound 10 (Comparative Example 2, described later), Compounds 1, 3, and 4 had comparable PLQYs, and the emission (PL) peak wavelengths were longer. Compared with Compound 10 (described later), Compounds 2, 5 to 9 had lower PLQYs, but the emission (PL) peak wavelengths were about 30 to 90 nm longer. Since the directivity improves and the invasiveness to the living body decreases as the emission wavelength becomes longer, Compounds 1 to 9 are superior to Compound 10 in this regard.

[0234] (Comparative Example 2) For Compound 10, a thin film was prepared in the same manner as in Example 2. The concentration of Compound 10 in the thin film was 3% by weight, and the results of measuring the normalized electronic absorption and emission (PL) spectra of the thin film are shown in Fig. 6. Also, the absorption wavelength λabs (nm), emission (PL) wavelength λem (nm), and photoluminescence quantum yield PLQY (Φf) (%) are shown in Table 12.

[0235] [Table 12]

[0236] The absorption peak wavelength of Compound 10 was 617 nm, which corresponds to a transition involving charge transfer from the ground state (S0) to the first singlet excited state (S1). When Compound 10 was excited at 340 nm, the emission (PL) peak wavelength was 703 nm, and the PLQY was 56%. Compared with Compounds 1 to 9, the absorption and emission (PL) wavelengths in the thin film of Compound 10 were shorter. Also, the PLQY of Compound 10 was comparable to those of Compounds 1, 3, and 4.

[0237] (Example 3) ASE characteristics Using the thin films of Compounds 1 to 9 prepared in Example 2, their potential for organic semiconductor lasers was evaluated. The thin films were photoexcited by a 337 nm pulsed nitrogen laser NL100 (Stanford Research Systems), where the CBP host strongly absorbs light. The pulse width of the pump laser is about 3.5 ns and its repetition frequency is 20 Hz. The pump intensity is controlled using a set of neutral density filters. The pump beam is focused into a 0.5 cm × 0.2 cm stripe. The emission (PL) spectrum from the edge of the organic layer was measured using an optical fiber connected to a charge-coupled device spectrometer. The experimental configuration is schematically shown in Fig. 7. The emission was detected using a PMA-50 multichannel spectrometer (Hamamatsu Photonics K.K.).

[0238] Fig. 8 shows the emission spectra of the CBP:Compound 1 (97:3 wt%) blend film before and after the ASE threshold. Fig. 9 shows the emission spectra of the blend film of 3 wt% of Compound 1 with CBP measured at various pump intensities below or above the threshold. At low excitation intensities, the PL spectrum was broad and independent of the pump intensity. At high excitation intensities, ASE occurred and a spectral narrowing of the emission band was observed. When exceeding the ASE threshold, the full width at half maximum (FWHM) decreased to 35 nm in this sample. This ASE effect is due to spontaneously emitted photons, which propagate in the film and are amplified by stimulated emission. Fig. 10 shows the output light intensity (left vertical axis) and the full width at half maximum (right vertical axis) emitted from the edge of the blend film as a function of the excitation intensity. The sharp change in the slope efficiency is directly related to the ASE threshold. For the CBP:Compound 1 (97:3 wt%) blend film, the ASE threshold was determined to be about 0.3 μJ / cm2. The ASE wavelength λASE (nm), the full width at half maximum FWHM (nm), and the ASE threshold Eth (μJ / cm2) of Compound 1 are summarized in Table 13.

[0239] [Table 13]

[0240] This ASE threshold is extremely low even when compared with the ASE threshold of Compound 10 described later in Comparative Example 3. Along with the broad emission (PL) spectrum of Compound 1 in the NIR region, the measured ASE threshold indicates that it is very promising for the future realization of efficient and tunable organic semiconductor lasers. Similarly, the ASE characteristics of Compounds 2 - 9 and 3 were measured. The results are summarized in Table 14.

[0241]

Table 14

[0242] Compounds 2 - 9 are capable of ASE oscillation on the longer wavelength side than Compound 10 (Comparative Example, described later), and Compounds 2, 5 - 9 showed ASE wavelengths exceeding 800 nm. Furthermore, Compound 3 showed a very low ASE threshold similar to Compound 1, indicating its usefulness.

[0243] (Comparative Example 3) Using the Compound 10 thin film prepared in Comparative Example 2, the ASE characteristics were evaluated in the same manner as in Example 3. Figure 11 shows the emission spectra before and after the ASE threshold of the blend film of CBP:Compound 10 (97:3 wt%). Figure 12 shows the emission spectra of the blend film of Compound 10 with 3 wt% of CBP measured at various pump intensities below or above the threshold. When exceeding the ASE threshold, the full width at half maximum (FWHM) decreased to 35 m in this sample. Figure 13 shows the output light intensity (left vertical axis) and the full width at half maximum (right vertical axis) emitted from the edge of the blend film as a function of the excitation intensity. The sharp change in the slope efficiency is directly related to the ASE threshold. In the case of the blend film of CBP:Compound 10 (97:3 wt%), the ASE threshold was determined to be approximately 1.5 μJ / cm2. The ASE wavelength λASE (nm), full width at half maximum (FWHM) (nm), and ASE threshold (Eth) (μJ / cm2) of Compound 5 are summarized in Table 15.

[0244]

Table 15

[0245] The ASE wavelength of Compound 10 is 756 nm, which is shorter than those of Compounds 1 to 9. This reflects the difference in the emission (PL) wavelengths observed in Example 2 and Comparative Example 2.

[0246] (Example 4) Distributed feedback laser (DFB laser) (1) Fabrication of DFB laser The glass substrate was cleaned by ultrasonic treatment using a neutral detergent, pure water, acetone, and isopropanol, followed by UV-ozone treatment. A 100-nm-thick SiO2 layer serving as the DFB grating was sputtered onto the glass substrate. The substrate was cleaned by ultrasonic treatment using isopropanol, followed by UV-ozone treatment. The SiO2 surface was treated with hexamethyldisilazane (HMDS) by spin-coating at 4,000 rpm for 15 seconds and annealed at 120 °C for 120 seconds. A resist layer with a thickness of approximately 70 nm was spin-coated onto the substrate from a ZEP520A-7 solution (Nippon Zeon Co., Ltd.) at 4,000 rpm for 30 seconds and baked at 180 °C for 240 seconds. Electron beam lithography was performed using a JBX-5500SC system (JEOL) to draw a grating pattern on the resist layer. After electron beam irradiation, the pattern was developed in a developer (ZEDN50, Nippon Zeon) at room temperature. The substrate was plasma-etched with CHF3 using an FA-1EA etching system (SAMCO) while using the patterned resist layer as an etching mask. The grating period (Λ) of the gratings was selected based on the following Bragg condition. mλBragg = 2neffΛm In the formula, m is the diffraction order, λBragg is the Bragg wavelength, and neff is the effective refractive index of the gain medium. The DFB substrate was cleaned by conventional ultrasonic treatment. A chloroform solution of Compound 1, 2, 5 and 4,4'-bis(N-carbazolyl)-1,10-biphenyl (CBP) (weight ratio, 3:97) (the concentration was the same as in Example 2) was spin-coated onto the DFB substrate to form a light-emitting layer. After directly forming a CYTOP polymer layer on its structure, it was covered with a sapphire lid having a thermal conductivity of 25 Wm-1K-1 at 300K, and a hybrid-order DFB laser having a structure of glass / SiO2 / 3 wt% of Compound 1, 2, 5:CBP / CYTOP / sapphire lid was fabricated (Figure 14).

[0247] (2) Performance of the DFB laser The performance of the fabricated DFB laser was first tested using a nitrogen laser emitting 3.5 ns pulses at a repetition rate of 20 Hz with an excitation wavelength of 337 nm for optical pumping. The emission spectrum measured perpendicular to the surface of the organic DFB laser containing Compound 1 is shown in Figure 15. When the grating lattice period (A2) of the grating is 550 nm, the DFB laser emission wavelength of Compound 1 is 851 nm, showing a narrow full width at half maximum (FWHM) of about 0.1 nm. Figure 16 plots the emission intensity (left vertical axis) and the full width at half maximum (right vertical axis) as a function of the excitation intensity. The clear change in slope is an indication of the laser oscillation threshold value, which was found to be 1.3 μJ / cm2. The performance of the DFB laser was similarly evaluated for Compounds 2 and 5. The diffraction grating periods (A2) (nm), DFB laser wavelengths λDFB (nm), FWHM (nm), and laser oscillation threshold values (Eth) (μJ / cm2) of the gratings used for Compounds 1, 2, and 5 are summarized in Table 16. It can be seen that the wavelength and threshold value of the DFB laser change depending on the grating period. The minimum values of the laser oscillation threshold values for Compounds 1 and 5 are lower than the minimum value of the threshold value of Compound 10 described later in Comparative Example 4. Furthermore, the wavelengths at the minimum threshold values of the DFB lasers of Compounds 1, 2, and 5 are longer than that of Compound 10, enabling oscillation in a longer-wavelength NIR region. These DFB characteristics, combined with the ASE characteristics in Example 3, indicate the promise of realizing an organic semiconductor laser.

[0248]

Table 16

[0249] (Comparative Example 4) Similar to Example 4, a DFB laser was fabricated using Compound 10 and measurements were taken. Fig. 17 shows the emission spectrum measured perpendicular to the surface of the organic DFB laser containing Compound 10. Fig. 18 shows a plot of the emission intensity (left vertical axis) and full width at half maximum (right vertical axis) against the excitation intensity. The diffraction grating period (A2) (nm), DFB laser wavelength λDFB (nm), full width at half maximum (FWHM) (nm), and laser oscillation threshold (Eth) (μJ / cm2) of the grating used with Compound 10 are summarized in Table 17.

[0250]

Table 17

[0251] The wavelength at the minimum threshold of the DFB laser of Compound 10 is shorter compared to Compounds 1, 2, and 5. This reflects the difference in the ASE wavelengths of both compounds observed in Example 3 and Comparative Example 3.

[0252] This application claims priority based on Japanese Patent Application No. 2021-209006 filed on December 23, 2021, and incorporates the entire disclosure thereof herein.

Claims

1. An organic electroluminescent device containing a compound represented by the general formula (1). 【Chemical 1】 (In general formula (1), X １ and X ２ each independently represents a halogen atom, a halogenated alkyl group, or a halogenated aryl group, and at least one of X １ and X ２ represents a halogenated alkyl group or a halogenated aryl group.) R １ ~R ６ each independently represents a hydrogen atom or a substituent, R １ and R ２ , R ２ and R ３ , R ３ and R ４ , R ４ and R ５ , R ５ and R ６ , R ６ and R ７ may together represent a ring. R ７ represents a group represented by the following general formula (2) or general formula (3). 【Chemical 2】 (In general formula (2), Ar １ represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group, and R ８ represents a substituent. A plurality of R ８ may be the same or different, and at least one R ８ is an electron-donating group. n8 represents an integer from 1 to the number of replaceable numbers in Ar １ ). [Chemical 3] (In general formula (3), R ９ to R １３ each independently represents a hydrogen atom or a substituent, and p represents an integer of 0 or 1 to 2.))

2. The organic electroluminescent device according to Claim 1, wherein the compound represented by the general formula (1) is a compound represented by the following general formula (4). 【Chemical Formula 4】 (In general formula (4), X １ , X ２ , and R ２ to R ６ are synonymous with general formula (1). Ar ２ and Ar ３ each independently represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group, or a heteroaryl-substituted heteroarylene group. R ３ and R ４ , R ４ and R ５ may together form a ring, R ２ may be bonded to Ar ２ to form a ring, and R ６ may be bonded to Ar ３ to form a ring. R １４ and R １５ each independently represents a substituent, and a plurality of R １４ may be the same or different, and at least one R １４ is an electron-donating group, and a plurality of R １５ may be the same or different, and at least one R １５ is an electron-donating group. n14 represents an integer from 1 to the number of substitutable numbers in Ar ２ and n15 represents an integer from 1 to the number of substitutable numbers in Ar ３ .)

3. In the general formula (4), R １４ and R １５ The organic electroluminescence device according to claim 2, wherein at least one of them is a substituted or unsubstituted diarylamino group.

4. In the general formula (4), Ar ２ and Ar ３ each independently consists of a benzene structure, a naphthalene structure, an anthracene structure or a fluorene structure, the organic electroluminescence element according to claim 2 or 3.

5. The organic electroluminescent device according to Claim 1, wherein the compound represented by the general formula (1) is a compound represented by the following general formula (5). 【Chemical Formula 5】 (In general formula (5), X １ , X ２ , and R ２ to R ６ are synonymous with the general formula (1). Ar ４ to Ar ７ each independently represents a substituted or unsubstituted aryl group, and each Ar ４ and each Ar ５ may be the same or different, and each Ar ６ and each Ar ７ may be the same or different. R １６ and R １７ each independently represent a substituent other than a substituted or unsubstituted diarylamino group, and when there are a plurality of R １６ and R １７ may be the same or different. R １６ and R ２ , R ３ and R ４ , R ４ and R ５ , R ６ and R １７ may together form a ring. n16 and n18 each independently represent 0 or an integer of 1 or more, n17 and n19 each independently represent an integer of 1 or more, n16 + n17 is an integer of 1 to 5, and n18 + n19 is an integer of 1 to 5.

6. R ４ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a halogen atom, or a group containing a boron difluoride diketonate ring, The organic electroluminescence device according to claim 1, 2 or 5.

7. R ３ and R ４ or R ４ and R ５ The organic electroluminescence element according to claim 1, 2 or 5, wherein R and R are combined together to form a ring.

8. The organic electroluminescent device according to Claim 1, wherein the compound represented by the general formula (1) is a compound represented by the following general formula (6). 【Chemical Formula 6】 (In general formula (6), X １ , X ２ , and R ２ to R ６ are synonymous with general formula (1). X １’ and X ２’ represent a halogen atom, a halogenated alkyl group, or a halogenated aryl group, and at least one of X １’ and X ２’ represents a halogenated alkyl group or a halogenated aryl group. R ２’ to R ６’ each independently represents a hydrogen atom or a substituent. R １８ and R １９ each independently represents one of the following Group A, R １８ and R ２ , R ３ and R ４ , R ４ and R ５ , R １９ and R ２‘ , R ３’ and R ４‘ , and R ４’ and R ５‘ may together form a ring, R ６ may combine with A to form a ring, R ６’ may combine with A to form a ring. A represents a linking group represented by the following general formula (7) or (9). 【Chemical Formula 7】 (In the general formula (7), n is 0 or an integer of 1 to 4, m is 0 or 1, A' represents an alkoxy group having 1 to 12 carbon atoms, and A'' represents a group represented by the following formula (8). 【Chemical Formula 8】 (In general formula (8), X １’’ and X ２’’ represent a halogen atom, a halogenated alkyl group or a halogenated aryl group, and at least one of X １’’ and X ２’’ represents a halogenated alkyl group or a halogenated aryl group, and R ２‘’ to R ６‘’ each independently represents a hydrogen atom or a substituent, and R ２０ represents one of the following Group A. 【Chemical Formula 9】 (In the formula, each R independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted aryl group having 6 to 10 carbon atoms, or a substituted or unsubstituted heteroaryl group.))) 【Chemical 10】 (In general formula (9), R ９ ~R １２ and p have the same meanings as in general formula (3).))

9. The organic electroluminescent device according to Claim 1, 2, 5, or 8, which emits delayed fluorescence.

10. The organic electroluminescent device according to Claim 1, 2, 5, or 8, which exhibits a maximum emission wavelength in the range of 700 to 1,500 nm.

11. An organic semiconductor laser including the organic electroluminescent device according to Claim 1, 2, 5, or 8.

12. The organic semiconductor laser according to Claim 11, wherein the organic semiconductor laser has an optical resonator structure composed of a secondary Bragg scattering region surrounded by a primary Bragg scattering region.

13. A thin film having a layer containing the compound represented by the general formula (1) according to Claim 1, the compound represented by the general formula (4) according to Claim 2, the compound represented by the general formula (5) according to Claim 5, or the compound represented by the general formula (6) according to Claim 8 on a substrate.

14. A compound represented by the following general formula (10). 【Chemical Formula 11】 (In general formula (10), X １ and X ２ each independently represents a halogen atom, a halogenated alkyl group or a halogenated aryl group, and at least one of X1 and X2 represents a halogenated alkyl group or a halogenated aryl group.) R ２ to R ６ each independently represents a hydrogen atom or a substituent. Ar ２ and Ar ３ each independently represents an arylene group, an aryl-substituted arylene group, a heteroaryl-substituted arylene group, a heteroarylene group, an aryl-substituted heteroarylene group or a heteroaryl-substituted heteroarylene group. R ３ and R ４ , R ４ and R ５ may together form a ring, R ２ may be bonded to Ar ２ to form a ring, and R ６ may be bonded to Ar ３ to form a ring. R １４ and R １５ each independently represent a substituent containing an aryl group, and when there are a plurality of Rs １４ they may be the same or different, and at least one R １４ is an electron-donating group containing an aryl group, and when there are a plurality of Rs １５ they may be the same or different, and at least one R １５ is an electron-donating group containing an aryl group, R １４ and R １５ at least one of which is a substituted or unsubstituted diarylamino group. n14 represents an integer from 1 to the number of substitutable numbers in Ar ２ and n15 represents an integer from 1 to the number of substitutable numbers in Ar ３ .)

15. A compound represented by the following general formula (11). 【Chemical 12】 (In general formula (11), X １ and X ２ each independently represents a halogen atom, a halogenated alkyl group or a halogenated aryl group, and at least one of X1 and X2 represents a halogenated alkyl group or a halogenated aryl group.) R ２ ~R ６ each independently represents a hydrogen atom or a substituent. Ar ４ ~Ar ７ each independently represents a substituted or unsubstituted aryl group, and each Ar present in plurality ６ and each Ar ７ may be the same or different, and each Ar present in plurality ４ and each Ar ５ may be the same or different. R １６ and R １７ each independently represents a substituent other than a substituted or unsubstituted diarylamino group, and a plurality of R １６ and R １７ may be the same or different. R １６ and R ２ , R ３ and R ４ , R ４ and R ５ , R ６ and R １７ may together form a ring. n16 and n18 each independently represent an integer of 0 or more, n17 and n19 each independently represent an integer of 1 or more, n16 + n17 is an integer from 1 to 5, and n18 + n19 is an integer from 1 to 5.)

16. A delayed fluorescence phosphor comprising the compound according to claim 14 or 15.

17. An organic semiconductor laser comprising the compound according to claim 14 or 15.

18. The organic semiconductor laser according to claim 17, wherein the organic semiconductor laser has an optical resonator structure composed of a secondary Bragg scattering region surrounded by a primary Bragg scattering region.

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