JP2020147543A - Triazine compound having 2'-aryl biphenylyl group - Google Patents

Abstract

To provide a triazine compound capable of contributing to manufacture of an organic electroluminescent element achieving a driving voltage, luminous efficiency and a service life, in a high dimension, and having high heat resistance; and to provide a material for the organic electroluminescent element, and a manufacturing method of the triazine compound.SOLUTION: A triazine compound has a specific structure shown by formula (1).SELECTED DRAWING: Figure 2

Description

The present disclosure relates to triazine compounds, methods for producing the same, and materials for organic electroluminescent devices.

Practical use of organic electroluminescent devices has begun, mainly for small mobile applications. However, although recent organic field effect light emitting devices have been gradually improved, further performance improvement is required. Here, the performance improvement of the organic electroluminescent element is to achieve a high degree of reduction of driving voltage, improvement of luminous efficiency, and extension of life without sacrificing any of them. There is a strong demand for its realization from the perspective of expanding applications.
Further, the organic electroluminescent element has begun to be put into practical use in applications other than small mobile applications, and is used, for example, as an in-vehicle display device.

Here, Patent Document 1 discloses a triazine compound having a specific structure as an electron transporting material.

Japanese Unexamined Patent Publication No. 2011-063584

However, even with the triazine compound according to Patent Document 1, further improvements are required in terms of drive voltage, luminous efficiency and life.
Furthermore, applications such as in-vehicle display devices are exposed to high-temperature environments, and even small mobile applications are increasingly used in various environments including high-temperature environments due to their widespread use. Therefore, the material used for the organic electroluminescent device is required to have further heat resistance.

Therefore, one aspect of the present disclosure contributes to the production of an organic electroluminescent element that achieves a high level of drive voltage, luminous efficiency, and life, and a triazine compound having high heat resistance, a material for the organic electroluminescent element, and the like. It is directed to provide a method for producing a triazine compound. Further, another aspect of the present disclosure is directed to provide an organic electroluminescent device that achieves a high level of drive voltage, luminous efficiency and life, and has excellent heat resistance.

The triazine compound according to one aspect of the present disclosure is represented by the formula (1):

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2.

In the method for producing a triazine compound represented by the formula (1) according to another aspect of the present disclosure, the compound represented by the formula (2) and the compound represented by the formula (3) are coupled by a coupling reaction. Including:

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2;
M ¹ represents ZnY ¹ , MgY ² , Sn (Y ³ ) ₃ , or B (OY ⁴ ) _{2 in} which two (OY ⁴ ) groups may be integrated to form a ring with a boron atom. ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ each independently represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ independently represents a hydrogen atom, an alkyl group or a phenyl group having 1 to 4 carbon atoms;
X ¹ represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom.

In the method for producing a triazine compound represented by the formula (1) according to another aspect of the present disclosure, the compound represented by the formula (4) and the compound represented by the formula (5) are coupled by a coupling reaction. Including:

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2;
X ² represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom;
M ² represents ZnY ¹ , MgY ² , Sn (Y ³ ) ₃ , or B (OY ⁴ ) _{2 in} which two (OY ⁴ ) groups may be integrated to form a ring with a boron atom. ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ each independently represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.

The material for an organic electroluminescent device according to another aspect of the present disclosure contains the above triazine compound.

The organic electroluminescent device according to another aspect of the present disclosure contains the above triazine compound.

According to one aspect of the present disclosure, a triazine compound having high heat resistance, a material for an organic electroluminescent device, and the triazine, which contribute to the production of an organic electroluminescent device that achieves a high level of drive voltage, light emission efficiency, and life. A method for producing a compound can be provided.
According to another aspect of the present disclosure, it is possible to provide an organic electroluminescent device which achieves a high level of drive voltage, luminous efficiency and life, and has excellent heat resistance.

It is schematic cross-sectional view which shows an example of the laminated structure of the organic electroluminescence element which concerns on one aspect of this disclosure. It is schematic cross-sectional view which shows the example of another laminated structure (the structure of the device Example-1) of the organic electroluminescence device which concerns on one aspect of this disclosure.

Hereinafter, the triazine compound according to one aspect of the present disclosure will be described in detail.
The triazine compound according to one aspect of the present disclosure is represented by the formula (1):

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2.

In the triazine compound having the structure represented by the formula (1), the present inventors can obtain a twist of the molecular structure by introducing a 1,2-phenylene site at an appropriate position in the molecule. I'm guessing that it can be solved.

Hereinafter, the triazine compound according to one aspect of the present disclosure (hereinafter, also simply referred to as triazine compound (1)) will be described in more detail.
The definitions of Ar ¹ , Ar ² , Ar ³ , Ar ⁴ , R, p and q in the triazine compound (1) will be described.

[About Ar ¹ and Ar ² ]
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group. Ar ¹ and Ar ² may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group.
Ar ¹ and Ar ² are preferably the same group in that the triazine compound (1) can be easily synthesized.
Further, it is preferable that Ar ¹ and Ar ² are independently phenyl groups or biphenylyl groups, respectively, because the triazine compound (1) is excellent in electron-transporting material properties.

[About Ar ³ ]
Ar ³ consists of 3 or 4 rings,
(I) Aromatic hydrocarbon groups,
(Ii) Nitrogen-containing heterocyclic group or
(Iii) Represents a heterocyclic group in which the heteroatom is a Group 16 element.

(I) Aromatic hydrocarbon group Examples of the aromatic hydrocarbon group include a phenanthryl group, an anthryl group, a pyrenyl group, a fluorenyl group, a benzofluorenyl group, a triphenylenyl group and a fluoranthenyl group. These groups may be substituted with one or more groups selected from the group consisting of fluorine atoms, methyl groups, and phenyl groups. Ar ³ is an aromatic hydrocarbon group consisting of an unsubstituted 3 or 4 ring or an aromatic hydrocarbon group consisting of a methyl group substituted with a methyl group in that the triazine compound (1) can be easily synthesized. It is preferably present, and a phenanthrenyl group, a dimethylfluorenyl group, and a triphenylenyl group are particularly preferable.

(Ii) Nitrogen-containing heterocyclic group Examples of the nitrogen-containing heterocycle include a benzo [b] quinolyl group, a benzo [c] quinolyl group, a benzo [f] quinolyl group, a benzo [g] quinolyl group, and a benzo [h]. Examples thereof include a quinolyl group, a phenazinyl group, an azapyrenyl group, a diazapyrenyl group, an azatriphenylenyl group, and a diazatriphenylenyl group. These groups may be substituted with one or more groups selected from the group consisting of fluorine atoms, methyl groups, and phenyl groups. Ar ³ is an unsubstituted benzo [c] quinolyl group, a benzo [h] quinolyl group, an azapyrenyl group, and an azatrife in that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device. It is preferably a nirenyl group or a diazatriphenylenyl group.

(Iii) Heterocyclic Group Examples of the heterocyclic group include a dibenzothiophenyl group, a dibenzofuranyl group, a benzonaphthofuranyl group and a benzonaphthophenyl group. These groups may be substituted with one or more groups selected from the group consisting of fluorine atoms, methyl groups, and phenyl groups. Ar ³ is preferably a dibenzofuranyl group or a dibenzothiophenyl group in that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device.

[About Ar ⁴ ]
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group. These groups may be substituted with one or more groups selected from the group consisting of fluorine atoms, methyl groups and phenyl groups. Ar ⁴ is preferably a phenyl group or a biphenylyl group because the triazine compound (1) can be easily synthesized.

[About R]
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, which may be independently substituted with an alkyl group having 1 to 4 carbon atoms. Examples of the aromatic hydrocarbon group represented by R include a phenyl group, a naphthyl group, a biphenylyl group, and a fluorenyl group.
The aromatic hydrocarbon group represented by R may be substituted with an alkyl group having 1 to 4 carbon atoms. The alkyl group having 1 to 4 carbon atoms may be a linear, branched or cyclic alkyl group, and specifically, a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group or a cyclo. Examples thereof include propyl group, butyl group, 2-butyl group, tert-butyl group and cyclobutyl group.
R is preferably a phenyl group or a biphenylyl group because the triazine compound (1) can be easily synthesized.

[About p]
p represents 0 or 1. It is preferable that p is 0 because the triazine compound (1) can be easily synthesized.

[About q]
q represents 1 or 2. Q is preferably 1 in that the triazine compound (1) can be easily synthesized.

[Specific example of triazine compound (1)]
Specific examples of the triazine compound (1) are not particularly limited, but for example, the compounds having the structures shown in 1-1 to 1-78 below can be specifically exemplified. The triazine compound (1) is preferably a compound represented by 1-1 or 1-2 in that it has good performance as an electron transporting material in an organic electroluminescent device.

Next, a method for producing a triazine compound according to another aspect of the present disclosure (hereinafter, referred to as a method for producing a triazine compound (1)) will be described.
The triazine compound (1) can be produced by step 1 or 2 shown in the following reaction formula.
That is, the method for producing the triazine compound (1) is as follows.
Including or causing a coupling reaction between the compound represented by the formula (2) and the compound represented by the formula (3), or
This includes a coupling reaction between the compound represented by the formula (4) and the compound represented by the formula (5).

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2;
M ¹ represents ZnY ¹ , MgY ² , Sn (Y ³ ) ₃ , or B (OY ⁴ ) _{2 in} which two (OY ⁴ ) groups may be integrated to form a ring with a boron atom. ;
M ² represents ZnY ¹ , MgY ² , Sn (Y ³ ) ₃ , or B (OY ⁴ ) _{2 in} which two (OY ⁴ ) groups may be integrated to form a ring with a boron atom. ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ each independently represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ independently represents a hydrogen atom, an alkyl or phenyl group having 1 to 4 carbon atoms;
X ¹ represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom;
X ² represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom.

Step 1 is a step of reacting the triazine compound (2) and the compound (3) in the presence of a catalyst to produce the triazine compound (1). In step 1, the desired product can be obtained in good yield by applying the reaction conditions of general coupling reactions such as Suzuki-Miyaura reaction, Negishi reaction, Tamao-Kumada reaction, and Stille reaction. When the reaction conditions of the Suzuki-Miyaura reaction are applied to step 1, it is preferable to carry out the reaction in the presence of a base. Further, as the catalyst, a palladium catalyst is preferable.

The compound represented by the formula (2) used in the step 1 is, for example, a method disclosed in Japanese Patent No. 6326930, or a general organometallic compound is synthesized from the compound represented by the formula (4). It can be synthesized using a reaction (see, eg, Angew. Chem. Int. Ed. 2007, 46, 5359-5363).
Examples of the compound represented by the formula (2) include compounds having the structures shown in 2-1 to 2-36 below, but the present invention is not limited thereto. In equations (2-1) to (2-36), M ¹ has the same definition as equation (2).

The group represented by M ¹ is not particularly limited, but for example, ZnY ¹ , MgY ² , Sn (Y ³ ) _3, or two (OY ⁴ ) groups are integrally ringed together with a boron atom. B (OY ⁴ ) _{2 and the} like which may form the above. Among these, B (OY ⁴ ) ₂ is preferable.

The ZnY ¹ and MgY ² are not particularly limited, and examples thereof include ZnCl, ZnBr, ZnI, MgCl, MgBr, and MgI.
The Sn (Y ³ ) ₃ is not particularly limited, and examples thereof include Sn (Me) ₃ and Sn (Bu) ₃ .
The B (OY ⁴ ) ₂ is not particularly limited, but for example, B (OH) ₂ , B (OMe) ₂ , B (O ⁱ Pr) ₂ , B (OBu) ₂ , B (OPh). ₂ etc. can be exemplified. Me is a methyl group, ⁱ Pr is an isopropyl group, Bu is a butyl group, and Ph is a phenyl group. Further, the example of B (OY ⁴ ) _{2 in} the case where two (OY ⁴ ) groups are integrally formed with a boron atom is not particularly limited, but for example, the following ( The groups represented by (I) to (VI) can be exemplified, and the group represented by (II) is preferable in terms of good yield.

Compound (3) used in step 1 can be produced, for example, according to International Publication No. 2017/209277. Moreover, you may use a commercially available product.
Examples of the compound (3) include the following 3-1 to 3-6, but the present invention is not limited thereto. In equations (3-1) to (3-6), X ¹ has the same definition as equation (3).

The desorbing group represented by X ¹ is not particularly limited, and examples thereof include a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group, and an iodine atom, and the yield of the triazine compound (1). A chlorine atom or a bromine atom is preferable in that However, it may be preferable to use a trifluoromethanesulfonyloxy group from the viewpoint of availability of raw materials.

The palladium catalyst that can be used in step 1 is not particularly limited, but specifically,
Palladium salts such as palladium chloride, palladium acetate, palladium trifluoroacetate, palladium nitrate;
Complex compounds such as π-allyl palladium chloride dimer, palladium acetylacetonato, tris (dibenzylideneacetone) dipalladium, bis (dibenzylideneacetone) palladium, dichlorobis (acetonitrile) palladium, dichlorobis (benzonitrile) palladium;
Dichlorobis (triphenylphosphine) palladium, tetrakis (triphenylphosphine) palladium, dichloro (1,1'-bis (diphenylphosphino) ferrocene) palladium, bis (tri-tert-butylphosphine) palladium, bis (tricyclohexylphosphine) Palladium complex having a tertiary phosphine such as palladium, dichlorobis (tricyclohexylphosphine) palladium as a ligand;
Can be exemplified.

A palladium complex having a tertiary phosphine as a ligand can also be prepared in a reaction system by adding a tertiary phosphine to a palladium salt or a complex compound. Examples of the tertiary phosphine that can be used at this time include triphenylphosphine, trimethylphosphine, tributylphosphine, tri (tert-butyl) phosphine, tricyclohexylphosphine, tert-butyldiphenylphosphine, 9,9-dimethyl-4, 5-bis (diphenylphosphino) xanthene, 2- (diphenylphosphino) -2'-(N, N-dimethylamino) biphenyl, 2- (di-tert-butylphosphino) biphenyl, 2- (dicyclohexylphosphino) ) Biphenyl, bis (diphenylphosphino) methane, 1,2-bis (diphenylphosphino) ethane, 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-kisilyl) phosphine, (±) -2,2'-bis (diphenylphosphine) ) -1,1'-binaphthyl, 2-dicyclohexylphosphino-2', 4', 6'-triisopropylbiphenyl and the like can be exemplified.

Among these, a palladium complex having a tertiary phosphine as a ligand is preferable in terms of good yield, and 2-dicyclohexylphosphino-2', 4', 6'-triisopropylbiphenyl or triphenylphosphine is coordinated. A palladium complex having a child is more preferable.

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 more preferably in the range of 1: 2 to 3: 1 in terms of good yield. preferable. The amount of the palladium catalyst used in step 1 is not limited, but the molar equivalent of the palladium catalyst is preferably in the range of 0.005 to 0.5 molar equivalent with respect to the boron compound in terms of good yield.

The base used in step 1 is not particularly limited, but for example, metal hydroxide salts such as sodium hydroxide, potassium hydroxide, and calcium hydroxide; sodium carbonate, potassium carbonate, lithium carbonate, and cesium carbonate. Metal carbonates such as; 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; sodium Metal alkoxides such as methoxide, potassium methoxide, sodium methoxide, potassium isopropyl oxide, potassium tert-butoxide; and the like can be mentioned. Among them, metal carbonate and metal phosphate are preferable, and potassium carbonate or potassium phosphate is more preferable in terms of good reaction yield. The amount of the base is not particularly limited, but the molar ratio of the base to the boron compound is preferably in the range of 1: 2 to 10: 1 and 1: 1 to 4: 1 in terms of good reaction yield. It is more preferable that it is in the range of.

Step 1 can be carried out in a solvent, which includes water; diisopropyl ether, dibutyl ether, cyclopentylmethyl ether (CPME), tetrahydrofuran (THF), 2-methyl tetrahydrofuran, 1,4-dioxane, dimethoxyethane. Etc.; Aromatic hydrocarbons such as benzene, toluene, xylene, mesityrene, tetralin; etc .; Carbonated esters such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, 4-fluoroethylene carbonate; ethyl acetate, acetic acid Esters such as butyl, methyl propionate, ethyl propionate, methyl butyrate, γ-lactone; amides such as N, N-dimethylformamide (DMF), dimethylacetamide (DMAc), N-methylpyrrolidone (NMP); N, N , N', N'-tetramethylurea (TMU), N, N'-dimethylpropylene urea (DMPU) and other ureas; and dimethyl sulfoxide (DMSO), methanol, ethanol, isopropyl alcohol, butanol, octanol, benzyl alcohol. , Ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, alcohols such as 2,2,2-trifluoroethanol; and the like; these may be mixed and used in any ratio. There is no particular limitation on the amount of solvent used. Of these, water, ether, amide, alcohol or a mixed solvent thereof is preferable from the viewpoint of good reaction yield, and a mixed solvent of THF and water or a mixed solvent of toluene and butanol is more preferable.

Step 1 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 100 ° C. to 160 ° C. in terms of good reaction yield.
Step 1 is obtained by performing a normal treatment after the reaction is completed. If necessary, it may be purified by recrystallization, column chromatography, sublimation, preparative HPLC or the like.

Next, step 2 will be described.
Step 2 is a step of reacting the compound represented by the formula (4) with the compound (5) represented by the formula (5) in the presence of a catalyst to produce the triazine compound (1). .. In step 2, the desired product can be obtained in good yield by applying the reaction conditions of general coupling reactions such as Suzuki-Miyaura reaction, Negishi reaction, Tamao-Kumada reaction, and Stille reaction. When the reaction conditions of the Suzuki-Miyaura reaction are applied to step 2, it is preferable to carry out the reaction in the presence of a base. Further, as the catalyst, a palladium catalyst is preferable.

The triazine compound represented by the formula (4) used in the step 2 can be produced, for example, according to the method disclosed in Japanese Patent No. 5812583.
The triazine compound represented by the formula (4) is a compound in which M ¹ in the formulas (2-1) to (2-36), which is a specific example of the compound represented by the formula (2), is replaced with X ^2. It can be exemplified. Here, X ² has the same definition as in equation (4).

The desorbing group represented by X ² is not particularly limited, and examples thereof include a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom, and the yield of the triazine compound (1). In that respect, a chlorine atom or a bromine atom is preferable.

The compound represented by the formula (5) used in the step 2 can be produced according to, for example, Journal of American Chemical Society, Vol. 134, p. 18932, 2012. Further, it can be synthesized from the compound represented by the formula (3) by using a reaction for synthesizing a general organometallic compound (for example, Angew.Chem.Int.Ed.2007,46,5359-5363). Commercially available products may be used.

The compound represented by the formula (5) can exemplify a skeleton in which X ¹ is replaced with M ² in the compounds represented by the formulas (3-1) to (3-6). M ² has the same definition as equation (5).

As the palladium catalyst, base, solvent, reaction temperature, and post-treatment (purification) that can be used in step 2, the same ones as those exemplified in step 1 can be exemplified, and the same applies to the preferable configurations thereof. is there.

The triazine compound (1) can be used, for example, in organic electronic device applications such as organic electroluminescent devices and photoelectric devices. Among these, the triazine compound (1) is preferably used as a material for an organic electroluminescent device.

<Material for organic electroluminescent device>
The material for an organic electroluminescent device according to one aspect of the present disclosure contains the above-mentioned triazine compound (1).
The triazine compound (1) can be used, for example, as an electron transport material for an organic electroluminescent device. The material for an organic electroluminescent device containing the triazine compound (1) achieves a high level of drive voltage, luminous efficiency and life, and contributes to the production of an organic electroluminescent device that can be used in various applications and in various environments. Is.

<Organic electroluminescent device>
The material for an organic electroluminescent device according to one aspect of the present disclosure contains the above-mentioned triazine compound (1).

<Organic electroluminescent device>
Hereinafter, an organic electroluminescent device containing the triazine compound (1) (hereinafter, may be simply referred to as an organic electroluminescent device) will be described.
The organic electroluminescent device according to one aspect of the present disclosure contains a triazine compound (1).
The configuration of the organic electroluminescent device is not particularly limited, and examples thereof include the configurations (i) to (v) shown below.
(I): Anode / light emitting layer / cathode (ii): anode / hole transport layer / light emitting layer / cathode (iii): anode / light 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

The triazine compound (1) may be contained in any of the above layers, but is superior to the group consisting of the light emitting layer and the layer between the light emitting layer and the cathode in that the organic electroluminescent device is excellent in light emitting characteristics. It is preferably contained in one or more selected layers. Therefore, in the case of the configurations shown in (i) to (v) above, it is preferable that the triazine compound (1) is contained in one or more layers selected from the group consisting of a light emitting layer, an electron transporting layer and an electron injecting layer. ..

Hereinafter, the organic electroluminescent device according to one aspect of the present disclosure will be described in more detail with reference to FIG. 1 by taking the configuration of the above (v) as an example.
The organic electroluminescent device shown in FIG. 1 has a so-called bottom emission type element configuration, but the organic electroluminescent device according to one aspect of the present disclosure is not limited to the bottom emission type element configuration. Absent. That is, the organic electroluminescent device according to one aspect of the present disclosure may have another known device configuration such as a top emission type.

FIG. 1 is a schematic cross-sectional view showing an example of a laminated structure of an organic electroluminescent device containing a triazine compound according to one aspect of the present disclosure.

The organic electroluminescent device 100 includes a substrate 1, an anode 2, a hole injection layer 3, a hole transport layer 4, a light emitting layer 5, an electron transport layer 6, an electron injection layer 7, and a cathode 8 in this order. However, some layers of these layers may be omitted, and conversely, other layers may be added. For example, a hole blocking layer may be provided between the light emitting layer 5 and the electron transport layer 6, the hole injection layer 3 is omitted, and the hole transport layer 4 is directly provided on the anode 2. May be good. Further, for example, a single layer having a function of a plurality of layers, such as an electron injection / transport layer having a function of an electron injection layer and a function of an electron transport layer in a single layer, is provided as a plurality of layers. It may be a configuration provided in place of. Further, for example, the single-layer hole transport layer 4 and the single-layer electron transport layer 6 may each be composed of a plurality of layers.

<< Layer containing triazine compound (1) >>
In the configuration example shown in FIG. 1, the organic electroluminescent device 100 contains the triazine compound (1) in one or more layers selected from the group consisting of the light emitting layer 5, the electron transport layer 6, and the electron injection layer 7. In particular, it is preferable that the electron transport layer 6 contains the triazine compound (1). The triazine compound (1) may be contained in a plurality of layers included in the organic electroluminescent device.
In the following, the organic electroluminescent device 100 in which the electron transport layer 6 contains the triazine compound (1) will be described.

[Board 1]
The substrate 1 is not particularly limited, and examples thereof include a glass plate, a quartz plate, and a plastic plate.
Examples of the substrate 1 include a glass plate, a quartz plate, a plastic plate, a plastic film, and the like. Among these, a glass plate, a quartz plate, and a light-transmitting plastic film are preferable.
Examples of the light-transmitting plastic film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, and polycarbonate (PC). ), Cellulose triacetate (TAC), cellulose acetate propionate (CAP) and the like.
In the case of a configuration in which light emission is extracted from the substrate 1 side, the substrate 1 is transparent with respect to the wavelength of light.

[Anode 2]
An anode 2 is provided on the substrate 1 (on the hole injection layer 3 side).
Examples of the anode material include metals, alloys, electrically conductive compounds and mixtures thereof having a high work function (for example, 4 eV or more). Specific examples of the anode material include metals such as Au; conductive transparent materials such as CuI, indium tin oxide (ITO; Indium Tin Oxide), SnO ₂ , and ZnO.
In the case of an organic electroluminescent device in which light emission is taken out through an anode, the anode is formed of a conductive transparent material that allows or substantially passes the light emission.

[Hole injection layer 3, hole transport layer 4]
A hole injection layer 3 and a hole transport layer 4 are provided in this order between the anode 2 and the light emitting layer 5 described later from the anode 2 side.

The hole injection layer and the hole transport layer have a function of transmitting holes injected from the anode to the light emitting layer, and the hole injection layer and the hole transport layer are interposed between the anode and the light emitting layer. Injects more holes into the light emitting layer with a lower electric field.

The hole injection layer and the hole transport layer also function as electron barrier layers. That is, the electrons injected from the cathode and transported from the electron injection layer and / or the electron transport layer to the light emitting layer are generated by the electron barrier existing at the interface between the light emitting layer and the hole injection layer and / or the hole transport layer. , Leakage into the hole injection layer and / or the hole transport layer is suppressed. As a result, the electrons are accumulated at the interface in the light emitting layer, which has the effect of improving the luminous efficiency and the like, and an organic electroluminescent device having excellent luminous performance can be obtained.

The material of the hole injection layer and the hole transport layer has at least one of hole injection property, hole transport property, and electron barrier property. The material of the hole injection layer and the hole transport layer may be either an organic substance or an inorganic substance.

Specific examples of the materials for the hole injection layer and the hole transport layer include triazole derivative, oxadiazole derivative, imidazole derivative, polyarylalkane derivative, pyrazoline derivative, pyrazolone derivative, phenylenediamine derivative, arylamine derivative, and amino-substituted chalcone. Derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilben derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers (particularly thiophene oligomers), porphyrin compounds, aromatic tertiary amine compounds, styryl Examples include amine compounds. Among these, porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds are preferable, and aromatic tertiary amine compounds are particularly preferable, because the performance of the organic electroluminescent element is good.

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-trill)-[1,1'-biphenyl] -4,4'-diamine (TPD), 2,2-bis (4-di-p-tolylaminophenyl) propane, 1,1-bis ( 4-di-p-trillaminophenyl) cyclohexane, N, N, N', N'-tetra-p-tolyl-4,4'-diaminobiphenyl, 1,1-bis (4-di-p-tolylaminophenyl) Phenyl) -4-phenylcyclohexane, bis (4-dimethylamino-2-methylphenyl) phenylmethane, bis (4-di-p-tolylaminophenyl) phenylmethane, N, N'-diphenyl-N, N'- 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] stillben, 4-N, N-diphenylamino -(2-Diphenylvinyl) benzene, 3-methoxy-4'-N, N-diphenylaminostillbenzene, N-phenylcarbazole, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] Examples thereof include biphenyl (NPD), 4,4', 4''-tris [N- (m-tolyl) -N-phenylamino] triphenylamine (MTDATA) and the like.

Further, inorganic compounds such as p-type-Si and p-type-SiC can also be mentioned as examples of the material of the hole injection layer and the material of the hole transport layer.

The hole injection layer and the hole transport layer may have a single structure made of one or more kinds of materials, or may have a laminated structure made of a plurality of layers having the same composition or different compositions.

[Light emitting layer 5]
A light emitting layer 5 is provided between the hole transport layer 4 and the electron transport layer 6 described later.
Examples of the material of the light emitting layer include a phosphorescent light emitting material, a fluorescent light emitting material, and a heat activation delayed fluorescent light emitting material. In the light emitting layer, electron-hole pairs are recombined, resulting in light emission.

The light emitting layer may consist of a single low molecular weight material or a single polymer material, but more generally it consists of a host material doped with a guest compound. The luminescence comes primarily from the dopant and can have any color.

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 specifically, DPVBi (4,4'-bis (2,2-diphenylvinyl) -1,1'-biphenyl), BCzVBi (4,4'-bis (9-ethyl-3-carbazobinylene) 1, 1'-biphenyl), TBADN (2-talshalbutyl-9,10-di (2-naphthyl) anthracene), ADN (9,10-di (2-naphthyl) anthracene), CBP (4,4'-bis) (Carbazole-9-yl) biphenyl), CDBP (4,4'-bis (carbazole-9-yl) -2,2'-dimethylbiphenyl), 2- (9-phenylcarbazole-3-yl) -9- [Examples include 4- (4-phenylphenylquinazoline-2-yl) carbazole, 9,10-bis (biphenyl) anthracene and the like.

Examples of the fluorescent dopant include anthracene, pyrene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, quinacridone, dicyanomethylenepyran compound, thiopyran compound, polymethine compound, pyrylium, thiapyrylium compound, fluorene derivative, perifrantene derivative, and indenoperylene. Derivatives, bis (azinyl) amine boron compounds, bis (azinyl) methane compounds, carbostryl compounds, and the like can be mentioned. The fluorescent dopant may be a combination of two or more selected from these.

Examples of the phosphorescent dopant include organometallic complexes of transition metals such as iridium, platinum, palladium, and osmium.

Specific examples of the fluorescent dopant and the phosphorescent dopant include Alq3 (tris (8-hydroxyquinoline) aluminum), DPAVBi (4,5'-bis [4- (di-p-tolylamino) styryl] biphenyl), perylene, and 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))) and the like can be mentioned.

Further, the light emitting material is not limited to being contained only in the light emitting layer. For example, the light emitting material may contain a layer (hole transport layer 4 or electron transport layer 6) adjacent to the light emitting layer. This makes it possible to further increase the current efficiency of the organic electroluminescent device.

The light emitting layer may have a single layer structure made of one or more kinds of materials, or may have a laminated structure made of a plurality of layers having the same composition or different compositions.

[Electronic transport layer 6]
An electron transport layer 6 is provided between the light emitting layer 5 and the electron injection layer 7 described later.
The electron transport layer has a function of transferring electrons injected from the cathode to the light emitting layer. By interposing the electron transport layer between the cathode and the light emitting layer, electrons are injected into the light emitting layer with a lower electric field.

As described above, the electron transport layer preferably contains the triazine compound (1). Further, the electron transport layer may further contain one or more selected from conventionally known electron transport materials in addition to the triazine compound (1).
When the triazine compound (1) is not contained in the electron transport layer but is contained in another layer, one or more selected from conventionally known electron transport materials should be used as the electron transport material constituting the electron transport layer. Can be done.

Conventionally known electron transporting materials include alkali metal complexes, alkaline earth metal complexes, earth metal complexes and the like. Examples of the alkali metal complex, alkaline earth metal complex, and earth metal complex include 8-hydroxyquinolinate lithium (Liq), bis (8-hydroxyquinolinate) zinc, and bis (8-hydroxyquinolinate) copper. , Bis (8-hydroxyquinolinate) manganese, tris (8-hydroxyquinolinate) aluminum, tris (2-methyl-8-hydroxyquinolinate) aluminum, tris (8-hydroxyquinolinate) gallium, bis (10-Hydroxybenzo [h] quinolinate) berylium, bis (10-hydroxybenzo [h] quinolinate) zinc, bis (2-methyl-8-quinolinate) chlorogallium, bis (2-methyl-8-quinolinate) (o -Crezolate) gallium, bis (2-methyl-8-quinolinate) -1-naphtholate aluminum, bis (2-methyl-8-quinolinate) -2-naphtholate gallium and the like can be mentioned.

The electron transport layer may have a single layer structure composed of one or more kinds of materials, or may have a laminated structure composed of a plurality of layers having the same composition or a different composition.

In the organic electroluminescent device according to this embodiment, an electron injection layer may be provided for the purpose of improving the electron injection property and the device characteristics (for example, luminous efficiency, constant voltage drive, or high durability).

[Electronic injection layer 7]
An electron injection layer 7 is provided between the electron transport layer 6 and the cathode 8 described later.
The electron injection layer has a function of transferring electrons injected from the cathode to the light emitting layer. By interposing the electron injection layer between the cathode and the light emitting layer, electrons are injected into the light emitting layer with a lower electric field.

Examples of the material of the electron injection layer include fluorenone, anthracinodimethane, diphenoquinone, thiopyrandioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fleolenilidenemethane, anthracinodimethane, and antron. Examples include organic compounds. Further, as the material of the electron injection layer, various oxides, nitrides, oxide nitrides such as SiO ₂ , AlO, SiN, SiON, AlON, GeO, LiO, LiON, TiO, TiON, TaO, TaON, TaN, C and the like are used. Inorganic compounds such as, etc. are also mentioned.

[Cathode 8]
A cathode 8 is provided on the electron injection layer 7.
In the case of an organic electroluminescence device having a configuration in which only light emitted through the anode is extracted, the cathode can be formed from any conductive material.
Examples of the material of the cathode include metals having a small work function (hereinafter, also referred to as electron-injectable metals), alloys, electrically conductive compounds, and mixtures thereof. Here, the metal having a small work function is, for example, a metal having a work function of 4 eV or less.
Specific examples of cathode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ). Examples include mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like.
Among these, from the viewpoint of electron injectability and durability against oxidation, a mixture of an electron injectable metal and a second metal which is a stable metal having a larger work function value than this, for example, magnesium / silver mixture, magnesium / Aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, lithium / aluminum mixture and the like are preferable.

[Formation method of each layer]
Each layer excluding the electrodes (anode, cathode) described above is formed by thinning by a known method such as a vacuum deposition method, a spin coating method, a casting method, or an LB (Langmuir-Blodgett method) method. be able to. The material of each layer may be used alone, or may be used together with a material such as a binder resin and a solvent if necessary.
The film thickness of each layer formed in this manner is not particularly limited and may be appropriately selected depending on the situation, but is usually in the range of 5 nm to 5 μm.

The anode and cathode can be formed by thinning the electrode material by a method such as vapor deposition or sputtering. A pattern may be formed through a mask having a desired shape during vapor deposition or sputtering, or a thin film may be formed by vapor deposition or sputtering, and then a pattern having a desired shape may be formed by photolithography.

The film thickness of the anode and the cathode is preferably 1 μm or less, and more preferably 10 nm or more and 200 nm or less.

The layer containing the triazine compound (1) may be formed in combination with the above-mentioned conventionally known electron-transporting material. Therefore, for example, the 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 the layer of the triazine compound (1).

The organic electroluminescent element may be used as a kind of lamp such as an illumination or an exposure light source, a projection device of a type that projects an image on a screen, or a display of a type that directly visually recognizes a still image or a moving image. It may be used as a device (display). When an organic electroluminescent element is used as a display device for moving image reproduction, the drive method may be a simple matrix (passive matrix) method or an active matrix method. Further, a full-color display device can be manufactured by using two or more kinds of organic electroluminescent elements having different emission colors.

The triazine compound (1) can provide an organic electroluminescent device which is remarkably excellent in luminous efficiency and long life characteristics as compared with a conventionally known triazine compound when used as an electron transport layer. Further, the triazine compound (1) is highly amorphous due to its steric hindrance skeleton and has high film quality stability. Therefore, effects such as improvement of driving stability of the organic electroluminescent element and improvement of luminous efficiency can be obtained. Furthermore, the triazine compound (1) has high chemical stability due to its characteristic skeleton, and can contribute to extending the life of the organic electroluminescent device.

By using the triazine compound (1) as an electron transport layer of an organic electroluminescent device, it is possible to provide a triazine compound capable of achieving high-dimensional drive in low voltage, high efficiency and long life of the device. Further, it is possible to provide an organic electroluminescent device using the triazine compound (1), which can exhibit low voltage drive, high efficiency and long life.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not construed as being limited to these Examples.

[ ^{1 1} H-NMR measurement]
¹ Bruker ASCEND 400 (400 MHz; manufactured by BRUKER) was used for ¹ H-NMR measurement. ^{1 1} H-NMR was measured using deuterated chloroform (CDCl ₃ ) as a measurement solvent and tetramethylsilane (TMS) as an internal standard substance.

[DSC measurement (glass transition temperature, crystallization temperature, melting point)]
The glass transition temperature, crystallization temperature, and melting point of Compounds 1-1 and 1-2 (obtained in Synthesis Examples 1 and 2 described later) are measured by the DSC (Differential scanning calorimetry) device DSC6220 (product name, Hitachi). It was carried out in a nitrogen atmosphere (flow rate 50 ml / min) using a high-tech science company. Aluminum oxide (Al ₂ O ₃ ) was used as a reference in the DSC measurement, and the sample was measured at 10 mg.
As a pretreatment for the measurement, the sample was melted by raising the temperature from 50 ° C. to a temperature above the melting point at a rate of 10 ° C./min, and then rapidly cooled with liquid nitrogen. Subsequently, the temperature of the pretreated sample was raised at a rate of 50 ° C. to 10 ° C./min, and the glass transition temperature, crystallization temperature and melting point were measured.

The glass transition temperature, crystallization temperature, and melting point of ETL-2 (details will be described later) are measured under a nitrogen atmosphere (flow rate 50 ml /) using a DSC (Differential scanning calorimetry) device DSC7020 (product name, manufactured by Hitachi High-Tech Science Co., Ltd.). It was done in min). Aluminum oxide (Al ₂ O ₃ ) was used as a reference in the DSC measurement, and the sample was measured at 10 mg.
As a pretreatment for the measurement, the sample was melted by raising the temperature from 30 ° C. to a temperature above the melting point at a rate of 15 ° C./min, and then rapidly cooled with liquid nitrogen. Subsequently, the temperature of the pretreated sample was raised from 30 ° C. to 5 ° C./min, and the glass transition temperature, crystallization temperature and melting point were measured.

[Measurement of light emission characteristics]
The light emitting characteristics of the organic electroluminescent device are evaluated using a luminance meter BM-9 (product name, manufactured by Topcon Techno House Co., Ltd.) by applying a direct current to the device manufactured in each example (described later) in an environment of 25 ° C. did.
In addition, commercially available reagents were used.

Synthesis Example-1

Under an argon atmosphere, 4,6-diphenyl-2- [3- (phenanthrene-9-yl) -5- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl) Phenyl] -1,3,5-triazine (7.83 g, 13 mmol), palladium acetate (144 mg, 0.64 mmol), 2-dicyclohexylphosphino-2', 4', 6'-triisopropylbiphenyl (XPhos, 544 mg) , 1.3 mmol) and cesium carbonate (12.5 g, 38 mmol) with 2'-chloro-1,1': 4', 1 "-terphenyl (4.40 g, 17 mmol) dissolved in THF (128 mL). The mixture was added dropwise and stirred at 80 ° C. for 17 hours. After allowing to cool to room temperature, water and methanol were added to the reaction mixture, the precipitated solid was filtered off, and the obtained solid was washed with water and methanol. The obtained solid was washed with toluene (115). It was dissolved in (° C., 470 mL), activated charcoal was added, and the mixture was stirred for a while. The liquid after stirring was filtered through Celite, and then a low boiling point was distilled off. The crude product was repeatedly recrystallized from toluene to obtain the desired product. 4,6-Diphenyl-2- [3 "-(phenanthrene-9-yl) -4'-phenyl-1,1': 2', 1" -terphenyl-5 "-yl] -1,3 , 5-Triazine (Compound 1-1) was obtained (3.94 g, 43%).

^{1 1} H-NMR (CDCl ₃ ): δ8.93 (dd, J = 1.6Hz, 1.6Hz, 1H), 8.82 (dd, J = 1.6Hz, 1.6Hz, 1H), 8.77 (D, J = 9.0Hz, 1H), 8.74 (ddd, J = 6.7Hz, 3.2Hz, 1.4Hz, 4H), 8.72-8.74 (m, 1H), 7. 92 (d, J = 1.9Hz, 1H), 7.89 (dd, J = 7.6Hz, 1.4Hz, 1H), 7.73-7.77 (m, 3H), 7.63-7 .71 (m, 3H), 7.59-7.62 (m, 2H), 7.54-7.58 (m, 5H), 7.44-7.53 (m, 6H), 7.36 -7.41 (m, 6H).

The glass transition temperature of the obtained compound 1-1 was 138 ° C., the melting point was 277 ° C., and the crystallization temperature was not observed.

Synthesis Example-2

Under an argon atmosphere, 4,6-diphenyl-2- [3- (phenanthrene-9-yl) -5- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl ] -1,3,5-triazine (5.00 g, 8.2 mmol), 2'-iodo-1,1': 3', 1 "-terphenyl (3.20 g, 9.0 mmol), tetrakis (tri) Phenylphosphine) palladium (472 mg, 0.41 mmol) and cesium carbonate (7.99 g, 25 mmol) were suspended in toluene (82 mL). This suspension was heated to reflux for 24 hours, allowed to cool, and then added to the reaction mixture. Water and methanol were added, and the resulting solid was filtered off. The obtained solid was dissolved in toluene (115 ° C., 120 ml), activated charcoal was added, and the mixture was stirred for a while. The stirred liquid was filtered through Celite and then brought to room temperature. By allowing to cool and filtering the precipitated solid, the target product, 4,6-diphenyl-2- [3 "- (phenanthrene-9-yl) -3'-phenyl-1,1': 2' , 1 "-terphenyl-5" -yl] -1,3,5-triazine (Compound 1-2) was obtained (4.10 g, 70%).

¹ HNMR (CDCl ₃ ) δ8.75 (d, J = 8.2Hz, 1H), 8.71 (d, J = 8.0, Hz, 1H), 8.66 (dd, J = 8.0, 1.6Hz, 4H), 8.56 (dd, J = 1.6, 1.6Hz, 1H), 8.43 (dd, J = 1.6, 1.6Hz, 1H), 7.87 (dd) , J = 7.7, 1.5Hz, 1H), 7.50-7.69 (m, 13H), 7.42 (ddd, J = 7.0, 7.0, 1.0Hz, 1H), 7.24-7.39 (m, 12H).

The melting point of the obtained compound 1-2 was 290 ° C., the crystallization temperature was 213 ° C., and the glass transition temperature was not observed.

Reference example-1

2- [3-Chloro-5- (phenanthrene-9-yl) phenyl] -4,6-diphenyl-1,3,5-triazine (1.00 g, 1.9 mmol), phenylboronic acid (1.00 g, 1.9 mmol) in a nitrogen atmosphere. 282 mg, 2.3 mmol), palladium acetate (13.0 mg, 0.06 mmol), 2-dicyclohexylphosphino-2', 4', 6'-triisopropylbiphenyl (XPhos, 55.0 mg, 0.12 mmol), 1 , 4-Dioxane (50 mL) and 2M-tripotassium phosphate aqueous solution (2.9 mL, 5.8 mmol) were added to a 300 mL four-necked flask, and the mixture was stirred at 95 ° C. for 6 hours. The obtained reaction solution was allowed to cool to room temperature, water (100 mL) was added to the reaction mixture, the precipitate was collected by filtration, and washed with water, methanol, and then hexane to obtain a gray powder. The obtained gray powder was purified by recrystallization with toluene, and the target product was 4,6-diphenyl-2- [5- (phenanthrene-9-yl) -biphenyl-3-yl] -1,3. A gray powder (yield 700 mg, yield 65%) of 5-triazine (compound ETL-1) was obtained.

^{1 1} H-NMR (CDCl ₃ ): δ7.45 (t, J = 7.3Hz, 1H), 7.52-7.63 (m, 9H), 7.67 (t, J = 7.2Hz, 1H) ), 7.73 (t, J = 7.8Hz, 1.3Hz, 2H), 7.84 (dd, J = 8.1Hz, 1.0Hz, 2H), 7.88 (s, 1H), 7 .98 (dd, J = 7.8Hz, 1.4Hz, 1H), 8.01-8.04 (m, 2H), 8.77-8.80 (m, 5H), 8.85 (d, J = 8.3Hz, 1H), 8.93 (t, J = 1.7Hz, 1H), 9.12 (t, J = 1.7Hz, 1H).

The obtained compound ETL-1 had a glass transition temperature of 108 ° C., a crystallization temperature of 207 ° C., and a melting point of 260 ° C.

From the above results, the compound 1-1, which is a triazine compound according to one aspect of the present disclosure, has a higher glass transition temperature than the conventionally known triazine compound (compound ETL-1) obtained in Reference Example-1. I understand. Furthermore, it was found that the triazine compound according to one aspect of the present disclosure has low crystallinity due to the characteristics of its skeleton, and the crystallization temperature is not detected or the crystallization temperature is high. Therefore, the triazine compound (1) can be expected to have high amorphousness when forming a thin film, and when an organic electroluminescent device using the triazine compound (1) is produced, it exhibits high drive stability and high luminous efficiency. Guess.

Then, device evaluation was carried out using the obtained compound.

Device Example-1 (see FIG. 2)

(Preparation of substrate 1 and anode 2)
As the substrate 1 having the anode 2 on its surface, a glass substrate with an ITO transparent electrode having a 2 mm wide indium tin oxide (ITO) film (film thickness 110 nm) patterned in a stripe shape was prepared. Then, after cleaning this substrate with isopropyl alcohol, surface treatment was performed by ozone ultraviolet cleaning.

(Preparation for vacuum deposition)
Each layer was vacuum-deposited by a vacuum-film deposition method on the surface-treated substrate after cleaning, and each layer was laminated and formed.
First, the glass substrate was introduced into a vacuum vapor deposition tank, and the pressure was reduced to 1.0 × 10 ^-4 Pa. Then, each layer was produced in the following order according to the film forming conditions of each layer. Each organic material was formed by a resistance heating method.

(Preparation of hole injection layer 3)
Sublimated and purified N- [1,1'-biphenyl] -4-yl-9,9-dimethyl-N- [4- (9-phenyl-9H-carbazole-3-yl) phenyl] -9H-fluorene-2 -Amine and 1,2,3-tris [(4-cyano-2,3,5,6-tetrafluorophenyl) methylene] cyclopropane were formed in a 99: 1 (mass ratio) ratio of 10 nm to form a positive film. The pore injection layer 3 was prepared. The film forming rate was 0.1 nm / sec.

(Preparation of the first hole transport layer 41)
Sublimated and purified N- [1,1'-biphenyl] -4-yl-9,9-dimethyl-N- [4- (9-phenyl-9H-carbazole-3-yl) phenyl] -9H-fluorene-2 -Amine was formed into a film at 85 nm at a rate of 0.2 nm / sec to prepare a first hole transport layer 41.

(Preparation of second hole transport layer 42)
Sublimated and purified N-phenyl-N- (9,9-diphenylfluorene-2-yl) -N- (1,1'-biphenyl-4-yl) amine was formed into a 5 nm film at a rate of 0.15 nm / sec. , The second hole transport layer 42 was prepared.

(Preparation of light emitting layer 5)
Sublimated and purified 3- (10-phenyl-9-anthril) -dibenzofuran and 2,7-bis [N, N-di- (4-tertbutylphenyl)] amino-bisbenzofurano-9,9'-spirofluorene And 20 nm were formed at a ratio of 95: 5 (mass ratio) to prepare a light emitting layer 5. The film forming rate was 0.1 nm / sec.

(Preparation of hole blocking layer 9)
Synthesis Example-1, 4,6-diphenyl-2- [3 "-(phenanthrene-9-yl) -4'-phenyl-1,1': 2', 1" terphenyl-5 "-yl synthesized in Example-1. ] -1,3,5-Triazine was deposited at a rate of 0.05 nm / sec at 6 nm to prepare a hole blocking layer 9.

(Preparation of electron transport layer 6)
Sublimated and purified 4,6-diphenyl-2- [5- (phenanthrene-9-yl) -3- (dimethylpyridin-3-yl) phenyl] -1,3,5-triazine and 8-hydroxyquinolinolate lithium (Hereinafter, Liq) was formed into a 25 nm film at a ratio of 50:50 (mass ratio) to prepare an electron transport layer 6. The film forming rate was 0.15 nm / sec.

(Preparation of electron injection layer 7)
A 1 nm film was formed on Liq at a rate of 0.02 nm / sec to prepare an electron injection layer 7.

(Preparation of cathode 8)
Finally, a metal mask was arranged so as to be orthogonal to the ITO stripe (anode 2) on the substrate 1, and a cathode 8 was formed. As the cathode, silver / magnesium (mass ratio 1/10) and silver were formed in this order at 80 nm and 20 nm, respectively, to form a two-layer structure. The film formation rate of silver / magnesium was 0.5 nm / sec, and the film formation rate of silver was 0.2 nm / sec.

As described above, the ² organic electroluminescent device 100 having a light emitting area of 4 mm as shown in FIG. 2 was manufactured. Each film thickness was measured with a stylus type film thickness measuring meter (DEKTAK, manufactured by Bruker).
Further, this device was sealed in a nitrogen atmosphere glove box having an oxygen and water concentration of 1 ppm or less. The sealing was performed by using a glass sealing cap and a film-forming substrate (element) with a bisphenol F type epoxy resin (manufactured by Nagase ChemteX Corporation).

Element reference example-1
In the element Example-1, 4,6-diphenyl-2- [5- (phenanthrene-9-yl) -biphenyl-3-yl] -1,3,5-triazine (ETL-) was applied to the hole blocking layer 9. Instead of forming 25 nm of 1) and Liq at a ratio of 50:50 (mass ratio) (deposition rate of 0.15 nm / sec), ETL-1 and Liq are formed at a ratio of 50:50 (mass ratio) of 25 nm. An organic electroluminescent device was produced in the same manner as in Device Example-1 except that a film (deposition rate of 0.15 nm / sec) was formed.

A direct current was applied to the produced organic electroluminescent device, and the luminescence characteristics were evaluated according to the method described in the above luminescence characteristic measurement.

As the light emission characteristics, the voltage (V) and the current efficiency (cd / A) when a current density of 10 mA / cm ² was passed were measured, and the element life during continuous lighting was measured. The device lifetime was measured luminance decay time at the time of continuous lighting when driving the initial luminance 1000 cd / m ^2, to measure the time required until the luminance (cd / m ²⁾ is reduced 3%. The values of voltage (V), current efficiency (cd / A), and lifetime are expressed as relative values when the device reference example-1 is set to 100. The results are shown in Table 1.

From Table 1, as compared with the reference example, the organic electroluminescent device using the triazine compound (1) has a high glass transition temperature and is excellent in heat resistance, and has a voltage, a luminous efficiency, and an element life. It has been found that it can be achieved at a higher level.

1. 1. Board 2. Anode 3. Hole injection layer 4. Hole transport layer 5. Light emitting layer 6. Electronic 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 (15)

Triazine compound represented by the formula (1):

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2. The triazine compound according to claim 1, wherein Ar ¹ and Ar ² are the same group. The triazine compound according to claim 1 or 2, wherein Ar ¹ and Ar ² are independently phenyl groups or biphenylyl groups, respectively. The triazine compound according to any one of claims 1 to 3, wherein Ar ³ is an aromatic hydrocarbon group consisting of 3 or 4 rings, which is unsubstituted or substituted with a methyl group. The triazine compound according to any one of claims 1 to 4, wherein Ar ³ is a phenanthrenyl group, a dimethylfluorenyl group or a triphenylenyl group. The triazine compound according to any one of claims 1 to 5, wherein Ar ⁴ is a phenyl group or a biphenylyl group. The triazine compound according to any one of claims 1 to 6, wherein R is a phenyl group or a biphenylyl group. The triazine compound according to any one of claims 1 to 7, wherein p is 0. The triazine compound according to any one of claims 1 to 8, wherein q is 1. A method for producing a triazine compound represented by the formula (1), which comprises a coupling reaction between a compound represented by the formula (2) and a compound represented by the formula (3).

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2;
M ¹ represents ZnY ¹ , MgY ² , Sn (Y ³ ) ₃ , or B (OY ⁴ ) _{2 in} which two (OY ⁴ ) groups may be integrated to form a ring with a boron atom. ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ each independently represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ independently represents a hydrogen atom, an alkyl or phenyl group having 1 to 4 carbon atoms;
X ¹ represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom. A method for producing a triazine compound represented by the formula (1), which comprises a coupling reaction between a compound represented by the formula (4) and a compound represented by the formula (5).

During the ceremony
Ar ¹ and Ar ² independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ consists of 3 or 4 rings,
Aromatic hydrocarbon groups,
Nitrogen-containing heterocyclic group or
Represents a heterocyclic group in which the heteroatom is a Group 16 element;
Ar ⁴ represents a phenyl group, a biphenylyl group or a naphthyl group;
Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group and a phenyl group;
R represents an aromatic hydrocarbon group of a monocyclic, linked ring, or condensed ring having 6 to 13 carbon atoms, each of which may be independently substituted with an alkyl group having 1 to 4 carbon atoms;
p represents 0 or 1;
q represents 1 or 2;
X ² represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom;
M ² represents ZnY ¹ , MgY ² , Sn (Y ³ ) ₃ , or B (OY ⁴ ) _{2 in} which two (OY ⁴ ) groups may be integrated to form a ring with a boron atom. ;
Y ¹ and Y ² independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ independently represents an alkyl or phenyl group having 1 to 4 carbon atoms;
Y ⁴ independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group. The method for producing a triazine compound according to claim 10 or 11, wherein M ¹ or M ² is B (OY ⁴ ) ₂ . The production method according to any one of claims 10 to 12, wherein the coupling reaction is carried out in the presence of a palladium catalyst having a tertiary phosphine as a ligand. Any of claims 10 to 13, wherein the coupling reaction is carried out in the presence of a palladium catalyst having triphenylphosphine or 2-dicyclohexylphosphine-2', 4', 6'-triisopropylbiphenyl as a ligand. The manufacturing method according to item 1. A material for an organic electroluminescent device containing the triazine compound according to any one of claims 1 to 9.

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