Triazine compounds for use in organic electroluminescent devices

Abstract

To provide a triazine compound that contributes to forming an organic electroluminescent device having high levels of luminous efficiency and long-life properties, and a material for organic electroluminescent devices and an organic electroluminescent device each comprising the triazine compound.SOLUTION: The present invention discloses a triazine compound represented by formula (1).SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a triazine compound, a material for an organic electroluminescent device containing the triazine compound, and an organic electroluminescent device. [Background technology]

[0002] Organic electroluminescent devices have begun to be put to practical use, primarily in small mobile devices. However, further expansion of their applications requires improved performance, and materials with high luminous efficiency and long life are required.

[0003] Patent Document 1 discloses a triazine compound that is a material for an organic electroluminescent device that is highly efficient and can reduce the driving voltage. Patent Document 2 discloses a triazine compound that is a material for an organic electroluminescent device that is highly efficient and can reduce the driving voltage. Patent Document 3 discloses a triazine compound that is a material for an organic electroluminescent device that has high heat resistance and can reduce the driving voltage. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-178931 [Patent Document 2] Korean Patent Publication No. 1666751 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-63584 Summary of the Invention [Problem to be solved by the invention]

[0005] However, there is a strong demand from the market for the expansion of applications and environments in which they can be used. With regard to the two properties of high luminous efficiency and long life, the triazine compounds disclosed in Patent Documents 1, 2 and 3 cannot be said to fully satisfy these, and there is a demand for materials that achieve these two properties at an even higher level.

[0006] Therefore, one aspect of the present disclosure is directed to providing a triazine compound that contributes to the formation of an organic electroluminescent device that exhibits high luminous efficiency and long life characteristics at a high level. Another aspect of the present disclosure is directed to providing a material for an organic electroluminescent device, which contains the triazine compound. Furthermore, still another aspect of the present disclosure is directed to providing an organic electroluminescent device that exhibits high luminous efficiency and long life characteristics at a high level. [Means for solving the problem]

[0007] According to one aspect of the present disclosure, there is provided a triazine compound represented by formula (1):

[0008] [ka]

[0009] During the ceremony, Ar 1 and Ar 2 each independently represents a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group, or a naphthylphenyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar 3 represents a polycyclic aromatic group which may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group; Ar 4 represents a phenyl group, an azaphenyl group, a diazaphenyl group, an azanaphthyl group, or a diazanaphthyl group, and these groups may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group; X 1 represents a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, a 1,4-naphthylene group, a 1,5-naphthylene group, a 2,6-naphthylene group, or a 2,7-naphthylene group; X 2represents a phenylene group, a naphthylene group, an azaphenylene group, a diazaphenylene group, an azanaphthylene group, or a diazanaphthylene group; p represents 1 or 2; However, when p is 2, two X 1 may be the same or different; q represents 0, 1 or 2; However, when q is 2, two X 2 may be the same or different.

[0010] According to another aspect of the present disclosure, there is provided a material for an organic electroluminescent device containing the above triazine compound.

[0011] According to yet another aspect of the present disclosure, there is provided an organic electroluminescent device containing the above triazine compound. [Effects of the Invention]

[0012] According to one aspect of the present disclosure, a triazine compound can be provided that contributes to the formation of an organic electroluminescent device that exhibits high luminous efficiency and long life characteristics at a high level. According to another aspect of the present disclosure, a material for an organic electroluminescent device that includes the triazine compound can be provided. Furthermore, according to yet another aspect of the present disclosure, an organic electroluminescent device that exhibits high luminous efficiency and long life characteristics at a high level can be provided. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view showing an example of a layered structure of an organic electroluminescence element according to one embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic cross-sectional view showing another example of a laminated structure (structure of element example 1) of an organic electroluminescence element according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] The triazine compound according to one embodiment of the present disclosure will be described in detail below.

[0015] <Triazine compounds> A triazine compound according to one embodiment of the present disclosure is a triazine compound represented by formula (1):

[0016] [ka]

[0017] During the ceremony, Ar 1 and Ar 2 each independently represents a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group, or a naphthylphenyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar 3 represents a polycyclic aromatic group which may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group; Ar 4 represents a phenyl group, an azaphenyl group, a diazaphenyl group, an azanaphthyl group, or a diazanaphthyl group, and these groups may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group; X 1 represents a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, a 1,4-naphthylene group, a 1,5-naphthylene group, a 2,6-naphthylene group, or a 2,7-naphthylene group; X 2 represents a phenylene group, a naphthylene group, an azaphenylene group, a diazaphenylene group, an azanaphthylene group, or a diazanaphthylene group; p represents 1 or 2; However, when p is 2, two X 1 may be the same or different; q represents 0, 1 or 2; However, when q is 2, two X 2 may be the same or different.

[0018] Hereinafter, the triazine compound represented by formula (1) may be referred to as triazine compound (1). Definitions of the substituents in triazine compound (1) and preferred specific examples thereof are as follows.

[0019] [Ar 1 and Ar 2 About Ar 1 and Ar 2 each independently represents a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group, or a naphthylphenyl group, and these groups may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group.

[0020] Ar 1 and Ar 2 Examples of the alkyl groups independently include a phenyl group, a p-tolyl group, an m-tolyl group, an o-tolyl group, a 2,4-dimethylphenyl group, a 3,5-dimethylphenyl group, a mesityl group, a 1-naphthyl group, a 2-naphthyl group, a biphenyl-2-yl group, a biphenyl-3-yl group, a biphenyl-4-yl group, a 3-methylbiphenyl-4-yl group, a 2'-methylbiphenyl-4-yl group, a 4'-methylbiphenyl-4-yl group, a 2,2'-dimethylbiphenyl-4-yl group, a 6-methylbiphenyl-3-yl group, a 5-methylbiphenyl- 3-yl group, 2'-methylbiphenyl-3-yl group, 4'-methylbiphenyl-3-yl group, 6,2'-dimethylbiphenyl-3-yl group, 5-methylbiphenyl-2-yl group, 6-methylbiphenyl-2-yl group, 2'-methylbiphenyl-2-yl group, 4'-methylbiphenyl-2-yl group, 6,2'-dimethylbiphenyl-2-yl group, 4-fluorophenyl group, 3-fluorophenyl group, 2-fluorophenyl group, 4-cyanophenyl group, 3-cyanophenyl group, 2-cyanophenyl group, and the like.

[0021] The triazine compound (1) has excellent electron transport properties, and therefore Ar 1 and Ar 2are each independently preferably a phenyl group or a biphenylyl group, more preferably a phenyl group or a 4-biphenylyl group.

[0022] [Ar 3 About In formula (1), Ar 3 represents a polycyclic aromatic group which may be substituted with one or more groups selected from the group consisting of methyl groups and phenyl groups.

[0023] In terms of ease of synthesis of the triazine compound (1), the polycyclic aromatic group is preferably a bicyclic, tricyclic or tetracyclic polycyclic aromatic group, and more preferably a tricyclic or tetracyclic polycyclic aromatic group.

[0024] The polycyclic aromatic group is preferably a hydrocarbon aromatic group, a nitrogen-containing six-membered ring aromatic group, or a chalcogen-containing aromatic group, since the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device.

[0025] Examples of aromatic hydrocarbon groups include naphthyl, phenanthryl, anthryl, pyrenyl, fluorenyl, benzofluorenyl, triphenylenyl, and fluoranthenyl groups. In order to contribute to the formation of a higher performance organic electroluminescent device from triazine compound (1), the aromatic hydrocarbon is preferably a phenanthryl, fluorenyl, anthryl, or triphenylenyl group, and more preferably a 9-phenanthryl, 9,9-dimethylfluoren-2-yl, or 2-triphenylenyl group.

[0026] Examples of the nitrogen-containing aromatic group include an azanaphthyl group, a diazanaphthyl group, a benzo[b]quinolyl group, a benzo[c]quinolyl group, a benzo[f]quinolyl group, a benzo[g]quinolyl group, a benzo[h]quinolyl group, a phenazinyl group, a phenanthrolinyl group, an azapyrenyl group, a diazapyrenyl group, an azatriphenylenyl group, a diazatriphenylenyl group, etc. In terms of ease of synthesis of the triazine compound (1), the nitrogen-containing 6-membered ring aromatic group is preferably an azanaphthyl group or a phenanthrolinyl group, more preferably a phenanthrolinyl group, and even more preferably a 1,10-phenanthrolinyl group.

[0027] Examples of the chalcogen-containing aromatic group include a benzothiophenyl group, a benzofuranyl group, a dibenzothiophenyl group, a dibenzofuranyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a xanthenyl group, a benzoxanthenyl group, etc. In terms of ease of synthesis of the triazine compound (1), the chalcogen-containing aromatic group is preferably a dibenzofuranyl group.

[0028] [Ar 4 About Ar 4 represents a phenyl group, an azaphenyl group, a diazaphenyl group, an azanaphthyl group, or a diazanaphthyl group, and these groups may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group.

[0029] Examples of the azaphenyl group, diazaphenyl group, azanaphthyl group, or diazanaphthyl group include a pyridyl group, a pyrazyl group, a pyrimidyl group, a quinolyl group, an isoquinolyl group, a naphthyridinyl group, a quinoxalinyl group, and a quinazolinyl group.

[0030] The triazine compound (1) contributes to the formation of a high-performance organic electroluminescent device, and therefore, Ar 4 but, a phenyl group, or It is preferably an azaphenyl group which may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group. Ar 4 However, it is more preferably a pyridyl group.

[0031] [X 1 About X 1 represents a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, a 1,4-naphthylene group, a 1,5-naphthylene group, a 2,6-naphthylene group, or a 2,7-naphthylene group.

[0032] The triazine compound (1) contributes to the formation of a high-performance organic electroluminescent device, 1 is preferably a phenylene group, and more preferably a 1,3-phenylene group or a 1,4-phenylene group.

[0033] [X 2 About X 2 represents a phenylene group, a naphthylene group, an azaphenylene group, a diazaphenylene group, an azanaphthylene group, or a diazanaphthylene group.

[0034] X 2Examples of the alkyl group include a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, a 2,3-pyridylene group, a 2,4-pyridylene group, a 2,5-pyridylene group, a 2,6-pyridylene group, a 2,4-pyrimidylene group, a 2,5-pyrimidylene group, a 2,5-pyrazylene group, a 1,2-naphthylene group, a 1,3-naphthylene group, a 1,4-naphthylene group, a 1,5-naphthylene group, a 1,6-naphthylene group, a 1,7-naphthylene group, a 1,8-naphthylene group, a 2,3-naphthylene group, a 2,4-naphthylene group, a 2,5-naphthylene group, a 2,6-naphthylene group, a 2,7-naphthylene group, and a 2,8-naphthylene group. Examples of the quinolylene group include a quinolylene group, a 2,3-quinolylene group, a 2,4-quinolylene group, a 2,5-quinolylene group, a 2,6-quinolylene group, a 2,7-quinolylene group, a 2,8-quinolylene group, a 3,4-quinolylene group, a 3,5-quinolylene group, a 3,6-quinolylene group, a 3,7-quinolylene group, a 3,8-quinolylene group, a 4,5-quinolylene group, a 4,6-quinolylene group, a 4,7-quinolylene group, a 4,8-quinolylene group, a 5,8-quinolylene group, a 2,3-quinoxalylene group, a 2,5-quinoxalylene group, a 2,6-quinoxalylene group, a 2,4-quinazolylene group, a 2,5-quinazolylene group, and a 2,6-quinazolylene group.

[0035] The triazine compound (1) contributes to the formation of a high-performance organic electroluminescent device, 2 However, it is preferably a phenylene group, and more preferably a 1,2-phenylene group or a 1,4-phenylene group.

[0036] [About p] p represents 1 or 2. However, when p is 2, two X 1 may be the same or different. It is more preferable that p is 1, since the triazine compound (1) contributes to the formation of an organic electroluminescent device with higher performance.

[0037] [About q] q represents 0, 1 or 2. However, when p is 2, two X 2 may be the same or different. It is more preferable that q is 0 or 1 in terms of ease of synthesis of the triazine compound (1).

[0038] [Preferred embodiment of triazine compound (1)] Ar 1 and Ar 2 is a phenyl group, Ar 3 is a 9-phenanthryl group, Ar 4 is a 3-pyridyl group, X 1 is a 1,3-phenylene group or a 1,4-phenylene group, q is 0, It is preferred that p is 1.

[0039] [Specific examples of triazine compound (1)] Specific examples of the triazine compound (1) include the following (1-1) to (1-93), but the present disclosure is not limited thereto. As the triazine compound (1), the compound represented by 1-1 or 1-46 is preferred because of its excellent performance as an electron transport material in an organic electroluminescent device.

[0040] [ka]

[0041] [ka]

[0042] [ka]

[0043] [ka]

[0044] [ka]

[0045] [ka]

[0046] [ka]

[0047] [ka]

[0048] [ka]

[0049] [ka]

[0050] [ka]

[0051] Next, a method for producing the triazine compound (1) will be described. The triazine compound (1) can be produced by the method shown in the following synthetic route. That is, a method for producing a triazine compound according to one embodiment of the present disclosure includes subjecting a triazine intermediate represented by formula (2) to a coupling reaction with a compound represented by formula (3) in the presence of a palladium catalyst:

[0052] [ka]

[0053] During the ceremony, Ar 1 , Ar 2 , Ar 3 , Ar4 , X 1 , X 2 , p and q have the same meanings as above; Y represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group, or an iodine atom; M is ZnZ 1 , MgZ 2 , Sn(Z 3 )3, or B(OZ 4 )2 represents; Z 1 and Z 2 each independently represents a chlorine atom, a bromine atom, or an iodine atom; Z 3 are the same or different and represent an alkyl group having 1 to 4 carbon atoms or a phenyl group, and three Z 3 may be the same or different; Z 4 are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group; two Z 4 may be the same or different 2 (OZ 4 ) groups may be taken together to form a ring with the boron atom.

[0054] Among these, M is the triazine compound (1) which is easy to synthesize, and B(OZ 4 )2 is preferred.

[0055] ZnZ 1 , MgZ 2 Examples of the cations include, but are not limited to, ZnCl, ZnBr, ZnI, MgCl, MgBr, and MgI. Sn(Z 3 Although there is no particular limitation on Sn(Me)3, Sn(Bu)3 and the like can be exemplified. B(OZ 4 )2 is not particularly limited, but examples thereof include B(OH)2, B(OMe)2, and B(O i Examples include B(Pr), B(OBu), and B(OPh). Me represents a methyl group. iPr represents an isopropyl group, Bu represents a butyl group, and Ph represents a phenyl group. 4 ) groups together with the boron atom to form a ring, 4 Examples of 2) are not particularly limited, but include the following groups (I) to (VI), and the group (II) is preferred in terms of good yield.

[0056] [ka]

[0057] The coupling reaction in the synthetic route is a step in which a triazine compound represented by formula (2) is reacted with a halogen compound represented by formula (3) in the presence of a palladium catalyst to produce triazine compound (1). The synthetic route can obtain the target product in good yield by applying reaction conditions for common coupling reactions such as the Suzuki-Miyaura reaction, Negishi reaction, Tamao-Kumada reaction, and Stille reaction. When applying the reaction conditions for the Suzuki-Miyaura reaction to the synthetic route, it is preferable to carry out the reaction in the presence of a base. The triazine compound used in the coupling reaction can be produced, for example, according to the method disclosed in WO 2017 / 052259. Alternatively, commercially available products may be used. The halogenated compound used in the coupling reaction can be produced, for example, according to Korean Patent Publication No. 2015 / 122343. Alternatively, commercially available products may be used. There are no particular restrictions on the molar equivalent of the halogenated compound used, but it is preferable to use 0.5 to 3.0 molar equivalents relative to the triazine compound in terms of a good reaction yield.

[0058] Examples of the group represented by Y include a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group, and an iodine atom. The trifluoromethanesulfonyloxy group is preferred in terms of the high yield of the triazine compound (1).

[0059] Palladium catalysts that can be used in the synthesis route are not particularly limited, but specific examples include: Palladium salts such as palladium chloride, palladium acetate, palladium trifluoroacetate, and palladium nitrate; Complex compounds such as π-allylpalladium chloride dimer, palladium acetylacetonate, tris(dibenzylideneacetone)dipalladium, bis(dibenzylideneacetone)palladium, dichlorobis(acetonitrile)palladium, and dichlorobis(benzonitrile)palladium; and Palladium complexes having a tertiary phosphine as a ligand, such as dichlorobis(triphenylphosphine)palladium, tetrakis(triphenylphosphine)palladium, dichloro[1,1'-bis(diphenylphosphino)ferrocene]palladium, bis(tri-t-butylphosphine)palladium, bis(tricyclohexylphosphine)palladium, and dichlorobis(tricyclohexylphosphine)palladium; Examples include:

[0060] Palladium complexes having a tertiary phosphine as a ligand can also be prepared in situ by adding a tertiary phosphine to a palladium salt or complex compound. Examples of tertiary phosphines that can be used in this case include triphenylphosphine, trimethylphosphine, tributylphosphine, tri(tert-butyl)phosphine, tricyclohexylphosphine, t-butyldiphenylphosphine, 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene, 2-(diphenylphosphino)-2'-(N,N-dimethylamino)biphenyl, 2-(di-t-butylphosphino)biphenyl, 2-(dicyclohexylphosphino)biphenyl, and bis(diphenylphosphine). Examples of the bis(diphenylphosphino) include 1,2-bis(diphenylphosphino)methane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,1'-bis(diphenylphosphino)ferrocene, tri(2-furyl)phosphine, tri(o-tolyl)phosphine, tris(2,5-xylyl)phosphine, (±)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl, and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl.

[0061] Among these, palladium complexes having a tertiary phosphine as a ligand are preferred in terms of good yield, and palladium complexes having 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl or triphenylphosphine as a ligand are more preferred.

[0062] The molar ratio of the tertiary phosphine to the palladium salt or complex compound is preferably in the range of 1:10 to 10:1, and from the viewpoint of a good yield, is more preferably in the range of 1:2 to 3:1. There is no limitation on the amount of the palladium catalyst used in the synthesis route, but from the viewpoint of a good yield, the molar equivalent of the palladium catalyst is preferably in the range of 0.005 to 0.5 molar equivalents relative to the triazine compound.

[0063] The synthesis route may be carried out by adding a base. The base to be used is not particularly limited, but examples thereof include metal hydroxide salts such as sodium hydroxide, potassium hydroxide, and calcium hydroxide; metal carbonates such as sodium carbonate, potassium carbonate, lithium carbonate, and cesium carbonate; metal acetates such as potassium acetate and sodium acetate; metal phosphates such as potassium phosphate and sodium phosphate; metal fluoride salts such as sodium fluoride, potassium fluoride, and cesium fluoride; and metal alkoxides such as sodium methoxide, potassium methoxide, sodium ethoxide, potassium isopropyl oxide, and potassium tert-butoxide. Among these, metal carbonates or metal phosphates are preferred in terms of good reaction yield, with potassium carbonate or potassium phosphate being more preferred. The amount of base is not particularly limited, but in terms of good reaction yield, the molar ratio of the base to the triazine compound is preferably in the range of 1:2 to 10:1, and more preferably in the range of 1:1 to 4:1.

[0064] The synthetic route can be carried out in a solvent, such as water; ethers such as diisopropyl ether, dibutyl ether, cyclopentyl methyl ether (CPME), tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,4-dioxane, and dimethoxyethane; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, and tetralin; carbonates such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and 4-fluoroethylene carbonate; ethyl acetate, butyl acetate, methyl propionate, methyl butyrate, and γ-lactopropanol. Examples of suitable solvents include esters such as methyl ether, ...

[0065] The synthesis route can be carried out at a temperature appropriately selected from 0°C to 200°C, and is preferably carried out at a temperature appropriately selected from 40°C to 150°C in terms of good reaction yield. The synthetic route can be obtained by carrying out the usual treatment after the completion of the reaction. If necessary, the product may be purified by recrystallization, column chromatography, sublimation, preparative HPLC, or the like.

[0066] The triazine compound (1) can be used for organic electronic devices such as organic electroluminescent devices and photoelectric devices.

[0067] <Materials for organic electroluminescent devices> A material for organic electroluminescent devices according to one embodiment of the present disclosure contains a triazine compound (1). The triazine compound (1) can be used, for example, as an electron transport material for organic electroluminescent devices. A material for organic electroluminescent devices containing the triazine compound (1) exhibits high luminous efficiency and long lifetime characteristics at a high level, and contributes to the production of organic electroluminescent devices that can be used for various applications.

[0068] <Organic electroluminescent device> The organic electroluminescent device containing the triazine compound (1) will be described below. The organic electroluminescent device contains a triazine compound (1).

[0069] The configuration of the organic electroluminescent device is not particularly limited, but examples thereof include the following configurations (i) to (v). (i): Anode / Emitting layer / Cathode (ii): Anode / hole transport layer / light-emitting layer / cathode (iii): Anode / Emitting layer / Electron transport layer / Cathode (iv): Anode / hole transport layer / light-emitting layer / electron transport layer / cathode (v): Anode / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode

[0070] The triazine compound (1) may be contained in any of the above layers, but is preferably contained in one or more layers selected from the group consisting of the light-emitting layer and the layer between the light-emitting layer and the cathode, in terms of excellent light-emitting properties of the organic electroluminescent device.

[0071] Therefore, in the case of the above configurations (i) to (v), it is preferable that the triazine compound (1) is contained in one or more layers selected from the group consisting of the light-emitting layer, the electron-transporting layer, and the electron-injecting layer.

[0072] Hereinafter, the organic electroluminescent device will be described in more detail with reference to FIG. 1, taking the above configuration (v) as an example.

[0073] 1 has a so-called bottom-emission type element configuration, the organic electroluminescent element is not limited to the bottom-emission type element configuration. In other words, the organic electroluminescent element may have other known element configurations, such as a top-emission type.

[0074] FIG. 1 is a schematic cross-sectional view showing an example of a layer structure of an organic electroluminescent device containing a triazine compound (1).

[0075] The organic electroluminescent device 100 comprises, in this order, a substrate 1, an anode 2, a hole injection layer 3, a hole transport layer 4, an emitting layer 5, an electron transport layer 6, an electron injection layer 7, and a cathode 8. However, some of these layers may be omitted, or other layers may be added. For example, a hole blocking layer may be provided between the emitting layer 5 and the electron transport layer 6, or the hole injection layer 3 may be omitted and the hole transport layer 4 may be provided directly on the anode 2.

[0076] Alternatively, a single layer having the functions of multiple layers, such as an electron injection / transport layer having the functions of both an electron injection layer and an electron transport layer, may be provided instead of the multiple layers.Furthermore, the single-layer hole transport layer 4 and the single-layer electron transport layer 6 may each be made up of multiple layers.

[0077] <<Layer Containing Triazine Compound (1)>>

[0078] 1, the organic electroluminescent device 100 contains a triazine compound (1) in one or more layers selected from the group consisting of a light-emitting layer 5, an electron transport layer 6, and an electron injection layer 7. It is preferable that the electron transport layer 6 contains the triazine compound (1). The triazine compound (1) may be contained in multiple layers of the organic electroluminescent device.

[0079] The organic electroluminescent device 100 in which the electron transport layer 6 contains the triazine compound (1) will be described below.

[0080] [Board 1] The substrate 1 is not particularly limited as long as it is a substrate that is commonly used by those skilled in the art for the relevant portion, and examples thereof include a glass plate, a quartz plate, a plastic plate, a plastic film, etc. Among these, a glass plate, a quartz plate, and a light-transmitting plastic film are preferred.

[0081] Examples of light-transmitting plastic films include films made of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC), cellulose acetate propionate (CAP), etc.

[0082] In the case where light is extracted from the substrate 1 side, the substrate 1 is transparent to the wavelength of the emitted light.

[0083] [Anode 2] An anode 2 is provided on the substrate 1 (on the hole injection layer 3 side).

[0084] Examples of anode materials include metals, alloys, electrically conductive compounds, and mixtures thereof, each having a large work function (e.g., 4 eV or more). Specific examples of anode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO, and ZnO.

[0085] In the case of an organic electroluminescent device configured so that light is extracted through the anode, the anode is formed from a conductive transparent material that is transparent or substantially transparent to the light emitted.

[0086] [Hole injection layer 3, hole transport layer 4] Between the anode 2 and the light-emitting layer 5, a hole injection layer 3 and a hole transport layer 4 are provided in this order from the anode 2 side.

[0087] The hole injection layer 3 and the hole transport layer 4 have the function of transporting holes injected from the anode to the light-emitting layer. By interposing the hole injection layer 3 and the hole transport layer 4 between the anode 2 and the light-emitting layer 5, a large number of holes can be injected into the light-emitting layer 5 with a lower electric field.

[0088] The hole injection layer 3 and the hole transport layer 4 also function as electron blocking layers. That is, electrons injected from the cathode 8 and transported from the electron injection layer 7 and / or the electron transport layer 6 to the light-emitting layer 5 are prevented from leaking to the hole injection layer 3 and / or the hole transport layer 4 by the electron barrier present at the interface between the light-emitting layer 5 and the hole injection layer 3 and / or the hole transport layer 4. As a result, the electrons accumulate at the interface within the light-emitting layer 5, which brings about effects such as improved luminous efficiency, and an organic electroluminescent device with excellent luminous performance is obtained.

[0089] The material for the hole injection layer 3 and the hole transport layer 4 has at least one of hole injection property, hole transport property, and electron barrier property. The material for the hole injection layer 3 and the hole transport layer 4 may be either an organic compound or an inorganic substance.

[0090] Specific examples of materials for the hole injection layer 3 and the hole transport layer 4 include triazole derivatives, oxadiazole derivatives, imidazole 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 copolymers, conductive polymer oligomers (particularly thiophene oligomers), porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds.

[0091] Among these, porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds are preferred in terms of good performance of the organic electroluminescent device, and aromatic tertiary amine compounds are particularly preferred.

[0092] Specific examples of the aromatic tertiary amine compound and the styrylamine compound include N,N,N',N'-tetraphenyl-4,4'-diaminophenyl, N,N'-diphenyl-N,N'-bis(m-tolyl)-[1,1'-biphenyl]-4,4'-diamine (TPD), 2,2-bis(4-di-p-tolylaminophenyl)propane, 1,1-bis(4-di-p-tolylaminophenyl)cyclohexane, N,N,N',N'-tetra-p-tolyl-4,4'-diaminobiphenyl, 1,1-bis(4-di-p-tolylaminophenyl)-4-phenylcyclohexane, bis(4-dimethylamino-2-methylphenyl)phenylmethane, bis(4-di-p-tolylaminophenyl)phenylmethane, N,N'-diphenyl-N,N'- Examples of such an amino acid include di(4-methoxyphenyl)-4,4'-diaminobiphenyl, N,N,N',N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis(diphenylamino)quadriphenyl, N,N,N-tri(p-tolyl)amine, 4-(di-p-tolylamino)-4'-[4-(di-p-tolylamino)styryl]stilbene, 4-N,N-diphenylamino-(2-diphenylvinyl)benzene, 3-methoxy-4'-N,N-diphenylaminostilbenzene, N-phenylcarbazole, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPD), and 4,4',4''-tris[N-(m-tolyl)-N-phenylamino]triphenylamine (MTDATA).

[0093] Furthermore, examples of materials for the hole injection layer 3 and the hole transport layer 4 include inorganic compounds such as p-type Si and p-type SiC.

[0094] The hole injection layer 3 and the hole transport layer 4 may have a single structure made of one or more materials, or may have a laminate structure made of multiple layers of the same or different compositions.

[0095] [Emitting layer 5] The light-emitting layer 5 is provided between the hole transport layer 4 and the electron transport layer 6 .

[0096] Examples of the material for the light-emitting layer 5, that is, the light-emitting material, include phosphorescent materials, fluorescent materials, and thermally activated delayed fluorescent materials. In the light-emitting layer 5, electron-hole pairs recombine, resulting in light emission.

[0097] The light-emitting layer 5 may consist of a single small molecule or single polymer material, but more commonly consists of a host material doped with a guest compound. Emission comes primarily from the dopant and can be of any color.

[0098] Examples of the host material include compounds having a biphenylyl group, a fluorenyl group, a triphenylsilyl group, a carbazole group, a pyrenyl group, and an anthryl group. More specific examples include DPVBi (4,4'-bis(2,2-diphenylvinyl)-1,1'-biphenyl), BCzVBi (4,4'-bis(9-ethyl-3-carbazovinylene)1,1'-biphenyl), TBADN (2-tert-butyl-9,10-di(2-naphthyl)anthracene), ADN (9,10-di(2-naphthyl)anthracene), CBP (4,4'-bis(carbazol-9-yl)biphenyl), CDBP (4,4'-bis(carbazol-9-yl)-2,2'-dimethylbiphenyl), 2-(9-phenylcarbazol-3-yl)-9-[4-(4-phenylphenylquinazolin-2-yl)carbazole, 9,10-bis(biphenyl)anthracene, and the like.

[0099] Examples of fluorescent dopants include anthracene, pyrene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, quinacridone, dicyanomethylenepyran compounds, thiopyran compounds, polymethine compounds, pyrylium, thiapyrylium compounds, fluorene derivatives, periflanthene derivatives, indenoperylene derivatives, bis(azinyl)amine boron compounds, bis(azinyl)methane compounds, carbostyril compounds, boron compounds, cyclic amine compounds, etc. The fluorescent dopant may be a combination of two or more selected from these.

[0100] Examples of phosphorescent dopants include complexes of metals such as iridium, platinum, palladium, and osmium.

[0101] Specific examples of fluorescent dopants and phosphorescent dopants include Alq3 (tris(8-hydroxyquinoline)aluminum), DPAVBi (4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl), perylene, bis[2-(4-n-hexylphenyl)quinoline](acetylacetonate)iridium(III), Ir(PPy)3 (tris(2-phenylpyridine)iridium(III)), and FIrPic (bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium(III))).

[0102] Furthermore, the luminescent material is not limited to being contained only in the luminescent layer 5. For example, the luminescent material may be contained in a layer adjacent to the luminescent layer 5 (the hole transport layer 4 or the electron transport layer 6). This can further increase the luminous efficiency of the organic electroluminescent device 100.

[0103] The light-emitting layer 5 may have a single layer structure made of one or more materials, or may have a laminate structure made of multiple layers of the same or different compositions.

[0104] [Electron transport layer 6] Between the light-emitting layer 5 and the electron injection layer 7, an electron transport layer 6 is provided.

[0105] The electron transport layer 6 has a function of transporting electrons injected from the cathode 8 to the light-emitting layer. By interposing the electron transport layer 7 between the cathode 8 and the light-emitting layer 5, electrons are injected into the light-emitting layer 5 at a lower electric field.

[0106] As described above, the electron transport layer 6 preferably contains the triazine compound (1). In addition to the triazine compound (1), the electron transport layer 6 may further contain one or more types selected from conventionally known electron transport materials.

[0107] When the triazine compound (1) is not contained in the electron transport layer 6 but is contained in another layer, one or more electron transport materials selected from conventionally known electron transport materials can be used as the electron transport material constituting the electron transport layer 6.

[0108] Conventionally known electron transporting materials include alkali metal compounds, alkaline earth metal compounds, transition metal compounds, zinc group element compounds, earth metal compounds, etc. Examples of alkali metal compounds, alkaline earth metal compounds, transition metal compounds, zinc group element compounds, earth metal compounds, etc. include 8-hydroxyquinolinatolithium (Liq), bis(8-hydroxyquinolinato)zinc, bis(8-hydroxyquinolinato)copper, bis(8-hydroxyquinolinato)manganese, tris(8-hydroxyquinolinato)aluminum, tris(2-methyl-8-hydroxyquinolinato)aluminum, tris(8-hydroxyquinolinato)aluminum, tris(8-hydroxyquinolinato) bis(2-methyl-8-quinolinato)gallium, bis(10-hydroxybenzo[h]quinolinato)beryllium, bis(10-hydroxybenzo[h]quinolinato)zinc, bis(2-methyl-8-quinolinato)chlorogallium, bis(2-methyl-8-quinolinato)(o-cresolate)gallium, bis(2-methyl-8-quinolinato)-1-naphtholatealuminum, and bis(2-methyl-8-quinolinato)-2-naphtholategallium are examples of chelate-type aryloxides.

[0109] The electron transport layer 6 may have a single layer structure made of one or more materials, or may have a laminate structure made of multiple layers of the same or different compositions.

[0110] In the organic electroluminescent device 100, an electron injection layer 7 may be provided for the purpose of improving electron injection properties and improving device characteristics (for example, luminous efficiency, low-voltage driving, or high durability).

[0111] [Electron injection layer 7] An electron injection layer 7 is provided between the electron transport layer 6 and the cathode 8. The electron injection layer 7 has a function of transferring electrons injected from the cathode to the light-emitting layer 5. By providing the electron injection layer between the cathode 8 and the light-emitting layer 5, electrons are injected into the light-emitting layer 5 at a lower electric field.

[0112] Examples of materials for the electron injection layer 7 include organic compounds such as fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylene tetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane, and anthrone.

[0113] Further, examples of materials for the electron injection layer 7 include inorganic compounds such as various oxides, fluorides, nitrides, and oxynitrides, such as SiO, AlO, SiN, SiON, AlON, GeO, LiO, LiON, TiO, TiON, TaO, TaON, TaN, LiF, C, and Yb.

[0114] [Cathode 8] A cathode 8 is provided on the electron injection layer 7. In the case of an organic electroluminescence element configured so that only emitted light that has passed through the anode 8 is extracted, the cathode 8 can be formed from any conductive material.

[0115] Examples of materials for the cathode 8 include metals with a low work function (hereinafter also referred to as electron injection metals), alloys, electrically conductive compounds, and mixtures thereof. Here, the metals with a low work function are, for example, metals with a work function of 4 eV or less.

[0116] Specific examples of materials for the cathode 8 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, and rare earth metals.

[0117] Among these, from the viewpoints of electron injection properties and durability against oxidation, etc., mixtures of an electron-injecting metal and a second metal that has a larger and more stable work function than the electron-injecting metal, such as magnesium / silver mixtures, magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al2O3) mixtures, and lithium / aluminum mixtures, are preferred.

[0118] [How each layer is formed] Each layer except for the electrodes (anode and cathode) described above can be formed into a thin film by a known method such as vacuum deposition, spin coating, casting, LB (Langmuir-Blodgett) method, etc. The material for each layer may be used alone or, if necessary, together with a material such as a binder resin or a solvent.

[0119] There are no particular limitations on the thickness of each layer thus formed, and it can be selected appropriately depending on the situation, but it is usually in the range of 5 nm to 5 μm.

[0120] The anode 1 and the cathode 8 can be formed by thinning an electrode material by a method such as vapor deposition or sputtering. A pattern may be formed using a mask of a desired shape during vapor deposition or sputtering, or a pattern of a desired shape may be formed by photolithography or the like after forming a thin film by vapor deposition or sputtering.

[0121] The thickness of the anode 1 and the cathode 8 is preferably 1 μm or less, and more preferably 10 nm or more and 200 nm or less.

[0122] The layer containing triazine compound (1) may be formed in combination with the above-mentioned conventionally known electron transporting material. For example, triazine compound (1) and the conventionally known electron transporting material may be co-deposited, or a layer of the conventionally known electron transporting material may be laminated on a layer of triazine compound (1).

[0123] The organic electroluminescent device may be used as a type of lamp for illumination or exposure light source, or may be used as a projection device that projects an image onto a screen or the like, or as a display device (display) that displays still images or moving images directly.

[0124] When organic electroluminescent elements are used as display devices for playing moving images, the driving method may be a passive matrix method or an active matrix method. In addition, by using two or more types of organic electroluminescent elements having different emission colors, it is possible to produce a full-color display device.

[0125] When used in an electron transport layer, the triazine compound (1) can provide an organic electroluminescent device that is significantly superior in driving voltage and luminous efficiency compared to conventionally known triazine compounds.

[0126] Therefore, it is expected that the driving stability and luminous efficiency of the organic electroluminescent device will be improved. Furthermore, the triazine compound (1) has a characteristic skeleton, which makes it highly chemically stable, and can contribute to extending the life of the organic electroluminescent device.

[0127] The triazine compound (1) can be used as an electron transport layer in an organic electroluminescent device to provide a triazine compound that can achieve low-voltage operation, high efficiency, and long life of the device at a high level. Furthermore, an organic electroluminescent device that can achieve high efficiency and long life using the triazine compound (1) can be provided. [Example]

[0128] The present disclosure will be described in more detail below based on examples, but the present disclosure should not be construed as being limited to these examples. Commercially available reagents were used.

[0129] [ 1 H-NMR measurement] 1For H-NMR measurements, a Bruker ASCEND 400 (400 MHz; manufactured by BRUKER) or a Bruker ULTRASHIELD Plus 400 (400 MHz; manufactured by BRUKER) was used. 1 H-NMR was measured using deuterated chloroform (CDCl3) or deuterated dimethyl sulfoxide (DMSO-d6) as a measurement solvent and tetramethylsilane (TMS) as an internal standard.

[0130] [Emission characteristics measurement] The light-emitting characteristics of the organic electroluminescent device were evaluated by applying a direct current to the device prepared in each example (described later) in a 25°C environment using a luminance meter BM-9 (product name, manufactured by Topcon Technohouse Corporation).

[0131] Synthesis Example 1 [ka]

[0132] Under an argon atmosphere, 3-(9-phenanthryl)-5-(3-pyridyl)phenyl trifluoromethanesulfonate (4.99 g, 10 mmol), 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine (3.48 g, 8.0 mmol), palladium acetate (54 mg, 0.24 mmol), and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (229 mg, 0.48 mmol) were dissolved in tetrahydrofuran (80 mL). A 2M aqueous solution of potassium carbonate (12 mL) was added and the mixture was stirred at 80 °C for 24 hours. After cooling to room temperature, water and methanol were added, the mixture was suspended, and the mixture was filtered. The residue was washed with water and methanol to obtain the crude product. The crude product was dissolved in chloroform, activated carbon was added, and the mixture was stirred for 30 minutes. The activated carbon was removed by filtration through Celite, and the solvent was then distilled off under reduced pressure. The resulting solid was purified by recrystallization (toluene) to give 2-[3'-(phenanthren-9-yl)-5'-(pyridin-3-yl)-(1,1'-biphenyl)-4-yl]-4,6-diphenyl-1,3,5-triazine (Compound 1-1) as a white solid (3.81 g, 75%).

[0133] 1 H-NMR(CDCl3)δ(ppm):9.04(d,J=1.7,1H),8.90(d,J=8.5Hz,2H),8.76-8.85(m,6H),8.67(dd,J=4.8,1.6Hz,1H),8.04-8.07(m,2H),8 .01(t,J=1.7Hz,1H),7.93-7.97(m,4H),7.85(s,1H),7.83(t,J=1.6Hz,1H),7.70-7.75(m,2H),7.57-7.68(m,8H),7.42-7.46(m,1H).

[0134] Synthesis Example 2 [ka]

[0135] Under an argon atmosphere, 2,4-biphenylyl-6-{3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl}-1,3,5-triazine (3.50 g, 8.0 mmol), 3-(9-phenanthryl)-5-(3-pyridyl)phenyl trifluoromethanesulfonate (4.60 g, 9.6 mmol), palladium acetate (54 mg, 0.24 mmol), and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (228 mg, 0.48 mmol) were suspended in THF (80 mL). To this suspension was added 2M aqueous potassium carbonate (12 mL) and heated to reflux for 15 hours. After cooling to room temperature, water and methanol were added to the reaction mixture, and the precipitated solid was collected by filtration. The resulting solid was purified by silica gel column chromatography (hexane / chloroform) followed by recrystallization (toluene) to obtain the desired 2-[3'-(phenanthren-9-yl)-5'-(pyridin-3-yl)-(1,1'-biphenyl)-3-yl]-4,6-diphenyl-1,3,5-triazine (compound 1-46) (4.10 g, 80%).

[0136] 1 H-NMR(CDCl3)δ(ppm):9.10(t,J=1.6Hz,1H),9.05(dd,J=2.4,0.7Hz,1H),8.82-8.85(m,2H),8 .76-8.80(m,5H),8.66(dd,J=1.6,4.8Hz,1H),8.13(dd,J=8.2,1.0Hz,1H),8.07(ddd,J=7.9,2 .3,1.7Hz,1H),8.02(t,J=1.7Hz,1H),7.99(t,J=1.6Hz,1H),7.95-7.98(m,2H),7.87(s,1H),7 .85(t,J=1.6Hz,1H),7.66-7.76(m,3H),7.55-7.65(m,8H),7.44(ddd,J=8.0,4.8,0.7Hz,1H).

[0137] Reference example-1 [ka]

[0138] Under an argon atmosphere, 3-bromo-5-chlorophenol (10.0 g, 48 mmol), 9-phenanthreneboronic acid (15.0 g, 68 mmol), and tetrakis(triphenylphosphine)palladium (1.67 g, 1.4 mmol) were suspended in 1,4-dioxane (100 mL). 5 M aqueous sodium hydroxide solution (29 mL) was added to the suspension, and the mixture was stirred at 100 °C for 16 hours. Water and chloroform were added to the reaction mixture. The organic layer was separated, and sodium sulfate was added to it. The sodium sulfate was filtered off, and the filtrate was evaporated to dryness under reduced pressure. The resulting crude product was purified by silica gel column chromatography (chloroform / ethyl acetate = 20 / 1) to obtain the desired 3-chloro-5-(phenanthrene-9-yl)phenol as a brown solid (14.2 g, 97%).

[0139] 1 H-NMR(CDCl3)δ(ppm):8.77(d,J=8.2Hz,1H),8.72(d,J=8.2Hz,1H),7.88-7.91(m,2H),7.60-7.71(m,4 H),7.54-7.58(m,1H),7.12(t,J=1.7Hz,1H),6.96(t,J=1.7Hz,1H),6.89-6.91(m,1H),5.28(brs,1H).

[0140] Reference example-2 [ka]

[0141] Under an argon atmosphere, 3-chloro-5-(9-phenanthryl)phenol (6.60 g, 22 mmol), bis(pinacolato)diboron (11.0 g, 43 mmol), tris(dibenzylideneacetone)dipalladium (496 mg, 0.54 mmol), 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (1.03 g, 2.2 mmol), and potassium acetate (8.50 g, 87 mmol) were suspended in dioxane (216 mL) and stirred at 110 °C for 24 hours. After cooling, the resulting mixture was extracted with chloroform and washed with saturated brine. The organic layer was concentrated and then purified by silica gel column chromatography to give 3-(phenanthren-9-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenol as a white solid (yield: 8.50 g, 99%).

[0142] 1 H-NMR(CDCl3)δ(ppm):8.70-8.77(m,2H),7.86-7.93(m,2H),7.51-7.69(m,6H ),7.34(dd,J=2.6,0.8Hz,1H),7.12-7.14(m,1H),4.95(s,1H),1.35(s,12H).

[0143] Reference example-3 [ka]

[0144] Under an argon atmosphere, 3-(phenanthren-9-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenol (8.50 g, 21 mmol), 3-bromopyridine (3.1 mL, 32 mmol), and tetrakis(triphenylphosphine)palladium (496 mg, 0.43 mmol) were dissolved in tetrahydrofuran (214 mL). 2M aqueous sodium carbonate solution (43 mL) was added and stirred at 80 °C overnight. After cooling to room temperature, the mixture was suspended in chloroform and filtered. The residue was washed with water, methanol, and chloroform to give 3-(phenanthren-9-yl)-5-(pyridin-3-yl)phenol as a white solid (6.30 g, 85%).

[0145] 1 H-NMR(DMSO-d6)δ(ppm):9.96(br,1H),8.87-8.96(m,3H),8.58(dd,J=4.7,1.5Hz,1H),8.12(dt,J=8.0,1.9Hz,1H),8.05(d,J=7 .8,1H),7.97(d,J=7.4,1H),7.88(s,1H),7.63-7.77(m,4H),7.47-7.51(m,1H),7.30(s,1H),7.21(t,J=1.9Hz,1H),7.00(s,1H).

[0146] Reference example-3 [ka]

[0147] Under an argon atmosphere, 3-(9-phenanthryl)-5-(3-pyridyl)phenol (6.30 g, 18 mmol) and pyridine (2.9 mL) were dissolved in dichloromethane (36 mL), and trifluoromethanesulfonic anhydride (3.6 mL, 21 mmol) was added dropwise and stirred at room temperature overnight. After completion of the reaction, the resulting mixture was extracted with chloroform and washed with water and saturated brine. The organic layer was concentrated and purified by silica gel chromatography to obtain a white solid of 3-(9-phenanthryl)-5-(3-pyridyl)phenyltrifluoromethanesulfonic acid (6.7 g, 77%).

[0148] 1 H-NMR(CDCl3)δ(ppm):8.92(d,J=2.4,1H),8.82(d,J=8.2Hz,1H),8.75(d,J=7.9Hz,1H),8.68(dd,J=4.8,1.6Hz,1H),7.92-7.96(m,2H),7. 87(d,J=8.2Hz,1H),7.81(t,J=1.5Hz,1H),7.70-7.74(m,3H),7.64-7.68(m,1H),7.58-7.62(m,2H),7.52-7.53(m,1H),7.41-7.45(m,1H).

[0149] Reference example-4 [ka]

[0150] 4,6-Diphenyl-2-[5-(9-phenanthryl)-3-(3-pyridyl)phenyl]-1,3,5-triazine (ETL-1) was synthesized by the method described in Example 6 of JP-A-2011-63584. 1 H-NMR(CDCl3)δ(ppm):9.22(s,1H),9.14(s,1H),9.13(d,J=5.4Hz,1H),8.89(d, J=8.4Hz,1H),8.83(d,J=8.4Hz,1H),8.80(d,J=7.1Hz,4H),8.60(d,J=8.1Hz,1H ),8.05(s,1H),8.02(d,J=7.1Hz,1H),7.96(d,J=8.1Hz,1H),7.90(brt,J=6.5Hz ,1H),7.90(s,1H),7.76-7.80(m,2H),7.72(t,J=7.0Hz,1H),7.59-7.67(m,8H)..

[0151] Next, the obtained compound was used to carry out device evaluation.

[0152] [Evaluation as electron transport layer 6] Element Example 1 (see Figure 2) (Prepare substrate 1 and anode 2) A glass substrate with an indium tin oxide (ITO) transparent electrode, on which a 2 mm wide striped pattern of an ITO film (thickness: 110 nm), was prepared as a substrate 1 having an anode 2 on its surface. Next, this substrate was washed with isopropyl alcohol, and then subjected to surface treatment by ozone ultraviolet cleaning.

[0153] (Preparation for vacuum deposition) After cleaning, each layer was deposited on the surface-treated substrate by vacuum deposition using a vacuum deposition method, and each layer was laminated. First, the glass substrate was placed in a vacuum deposition chamber. -4 The pressure was reduced to 100 Pa. Then, each layer was formed in the following order according to the film formation conditions. Each organic material was formed by resistance heating.

[0154] (Fabrication of Hole Injection Layer 3) Sublimation-purified N-[1,1'-biphenyl]-4-yl-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluoren-2-amine and 1,2,3-tris[(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane were mixed in a mass ratio of 99:1 to form a 10 nm film, producing hole injection 3. The film formation rate was 0.1 nm / sec.

[0155] (Fabrication of First Hole Transport Layer 41) Sublimation-purified N-[1,1'-biphenyl]-4-yl-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluoren-2-amine was deposited at a rate of 0.2 nm / sec to form a 85 nm film, thereby forming a first hole transport layer 41.

[0156] (Fabrication of the second hole transport layer 42) Sublimation-purified N-phenyl-N-(9,9-diphenylfluoren-2-yl)-N-(1,1′-biphenyl-4-yl)amine was deposited at a rate of 0.15 nm / sec to form a film of 5 nm, thereby forming second hole transport layer 42 .

[0157] (Fabrication of Light-Emitting Layer 5) Sublimation-purified 3-(10-phenyl-9-anthryl)-dibenzofuran and 2,7-bis[N,N-di-(4-tertbutylphenyl)]amino-bisbenzofurano-9,9'-spirofluorene were mixed in a mass ratio of 95:5 to form a 20 nm film, thereby producing the light-emitting layer 5. The film formation rate was 0.1 nm / sec.

[0158] (Fabrication of Hole Blocking Layer 9) Sublimation-purified 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)[1,1'-biphenyl]-3-yl]-4,6-diphenyl-1,3,5-triazine was deposited at a rate of 0.05 nm / sec to form a 6 nm film as a hole-blocking layer 9 .

[0159] (Fabrication of Electron Transport Layer 6) 2-[3'-(phenanthren-9-yl)-5'-(pyridin-3-yl)-(1,1'-biphenyl)-4-yl]-4,6-diphenyl-1,3,5-triazine (compound 1-1) synthesized in Synthesis Example 1 and 8-hydroxyquinolinolatolithium (hereinafter referred to as Liq) were mixed in a mass ratio of 50:50 to form a 25 nm film, thereby producing an electron transport layer 6. The film formation rate was 0.15 nm / sec.

[0160] (Fabrication of Electron Injection Layer 7) Liq was deposited at a rate of 0.02 nm / sec to a thickness of 2 nm to form an electron injection layer 7 .

[0161] (Fabrication of cathode 8) Finally, a metal mask was placed perpendicular to the ITO stripes (anode 2) on the substrate 1, and a cathode 8 was formed. The cathode had a two-layer structure, with silver / magnesium (mass ratio 1 / 10) and silver deposited in that order to thicknesses of 80 nm and 20 nm, respectively. The silver / magnesium deposition rate was 0.5 nm / sec, and the silver deposition rate was 0.2 nm / sec.

[0162] As a result, the light-emitting area of ​​4mm as shown in Figure 2 2An organic electroluminescent device 100 was produced. The thickness of each film was measured using a stylus film thickness measuring instrument (DEKTAK, manufactured by Bruker). The device was then sealed in a nitrogen atmosphere glove box with an oxygen and moisture concentration of 1 ppm or less by sealing the glass sealing cap and the film-formed substrate (device) with bisphenol F epoxy resin (manufactured by Nagase ChemteX Corporation).

[0163] Element Example 2 An organic electroluminescent device was produced in the same manner as in Device Example 1, except that in Device Example 1, a 25 nm film (film formation rate: 0.15 nm / sec) of Compound A-49 and Liq was formed in a mass ratio of 50:50 as the electron transport layer 6 instead of a 25 nm film (film formation rate: 0.15 nm / sec) of 2-[3'-(phenanthren-9-yl)-5'-(pyridin-3-yl)-(1,1'-biphenyl)-3-yl]-4,6-diphenyl-1,3,5-triazine (Compound 1-46) synthesized in Synthesis Example 2 and Liq in a mass ratio of 50:50. Element reference example 1

[0164] An organic electroluminescent device was produced in the same manner as in Device Example 1, except that, instead of forming a 25 nm film (film formation rate: 0.15 nm / sec) of 2-[3′-(phenanthren-9-yl)-5′-(pyridin-3-yl)-(1,1′-biphenyl)-4-yl]-4,6-diphenyl-1,3,5-triazine (Compound 1-1) and Liq in a mass ratio of 50:50, a 25 nm film (film formation rate: 0.15 nm / sec) of ETL-1 and Liq was formed in a mass ratio of 50:50.

[0165] A direct current was applied to the produced organic electroluminescent device, and the light-emitting characteristics were evaluated according to the method described above for measuring light-emitting characteristics.

[0166] The light-emitting characteristics are as follows: current density 10mA / cm 2 The current efficiency (cd / A) was measured when the current was passed through the device, and the device lifespan during continuous lighting was measured. The device lifespan was measured when the initial luminance was 1000 cd / m2 The luminance decay time was measured during continuous lighting when driven at 1000 Hz, and the luminance (cd / m 2 The time required for the current efficiency (cd / A) to decrease by 5% was measured. The current efficiency (cd / A) and lifetime values ​​were expressed as relative values ​​with the value of Reference Example Element-1 taken as 100. The results are shown in Table 1.

[0167] [Table 1] [Explanation of symbols]

[0168] 1. Substrate 2.Anode 3. Hole injection layer 4. Hole transport layer 5. Emitting layer 6.Electron transport layer 7.Electron injection layer 8.Cathode 9. Hole-blocking layer 51. First hole transport layer 52. Second hole transport layer 100. Organic electroluminescent device

Claims

1. Triazine compounds represented by formula (1): 【Chemistry 1】 During the ceremony, Ar １ and Ar ２ each independently represents a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group, or a naphthylphenyl group, and these groups may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar ３ represents a polycyclic aromatic group which may be substituted with one or more groups selected from the group consisting of a methyl group and a phenyl group; Ar ４ represents a pyridyl group; X １ represents a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, a 1,4-naphthylene group, a 1,5-naphthylene group, a 2,6-naphthylene group, or a 2,7-naphthylene group; X ２ represents a phenylene group, a naphthylene group, an azaphenylene group, a diazaphenylene group, an azanaphthylene group, or a diazanaphthylene group; p represents 1 or 2; However, when p is 2, two X １ may be the same or different; q represents 0, 1 or 2; However, when q is 2, two X ２ may be the same or different.

2. Ar １ and Ar ２ is a phenyl group, Ar ３ is a 9-phenanthryl group, Ar ４ is a 3-pyridyl group, X １ is a 1,3-phenylene group or a 1,4-phenylene group, q is 0, The triazine compound of claim 1 , wherein p is 1.

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