JP2022157906A - Triazine compound for use in organic electroluminescent device - Google Patents

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 The present disclosure relates to a triazine compound, an organic electroluminescent device material containing the triazine compound, and an organic electroluminescent device.

Organic electroluminescence devices have begun to be put into practical use, mainly for small mobile applications. However, performance improvement is essential for further expansion of applications, and materials having high luminous efficiency characteristics and long life characteristics are required.

Patent Literature 1 discloses a triazine compound which is a material for an organic electroluminescence device capable of reducing driving voltage with high efficiency.
Patent Literature 2 discloses a triazine compound that is a material for organic electroluminescence devices capable of reducing driving voltage with high efficiency.
Patent Document 3 discloses a triazine compound which is a material for an organic electroluminescence device having high heat resistance and capable of reducing driving voltage.

JP 2017-178931 A Korean Patent Publication No. 1666751 JP 2011-63584 A

However, the demand from the market for expansion of applications and expansion of usable environments is very strong, and the triazine compounds according to Patent Documents 1, 2 and 3 sufficiently satisfy these two characteristics of high luminous efficiency and long life characteristics. However, there is a demand for a material that achieves the above two characteristics at a higher level.

Accordingly, 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 electroluminescence device containing the triazine compound.
Furthermore, still another aspect of the present disclosure is directed to providing an organic electroluminescence device that exhibits high luminous efficiency and long life characteristics at a high level.

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

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group or a naphthylphenyl group, and these groups are selected from the group consisting of a fluorine atom, a methyl group and a cyano group. optionally substituted by one or more substituents;
Ar ³ represents a polycyclic aromatic group optionally substituted with one or more 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 selected from the group consisting of a methyl group and a phenyl group;
X ¹ is a 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group, 2,6-naphthylene group or 2,7- represents a naphthylene group;
X2 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;
provided that 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.

According to another aspect of the present disclosure, there is provided a material for an organic electroluminescence device containing the triazine compound.

According to still another aspect of the present disclosure, an organic electroluminescent device containing the above triazine compound is provided.

According to one aspect of the present disclosure, it is possible to provide 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. Further, according to another aspect of the present disclosure, it is possible to provide a material for an organic electroluminescence device containing the triazine compound. Furthermore, according to still another aspect of the present disclosure, it is possible to provide an organic electroluminescence device that exhibits high luminous efficiency and long life characteristics to a high degree.

1 is a schematic cross-sectional view showing an example of a layered structure of an organic electroluminescence element according to one aspect of the present disclosure; FIG. FIG. 4 is a schematic cross-sectional view showing another example of the layered structure of the organic electroluminescence element according to one aspect of the present disclosure (structure of Element Example-1).

The triazine compound according to one aspect of the present disclosure will be described in detail below.

<Triazine compound>
A triazine compound according to one aspect of the present disclosure is a triazine compound represented by formula (1):

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group or a naphthylphenyl group, and these groups are selected from the group consisting of a fluorine atom, a methyl group and a cyano group. optionally substituted by one or more substituents;
Ar ³ represents a polycyclic aromatic group optionally substituted with one or more 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 selected from the group consisting of a methyl group and a phenyl group;
X ¹ is a 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group, 2,6-naphthylene group or 2,7- represents a naphthylene group;
X2 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;
provided that 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.

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

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

Ar ¹ and Ar ² each independently include, for example, a phenyl group, p-tolyl group, m-tolyl group, o-tolyl group, 2,4-dimethylphenyl group, 3,5-dimethylphenyl group and mesityl group. , 1-naphthyl group, 2-naphthyl group, biphenyl-2-yl group, biphenyl-3-yl group, biphenyl-4-yl group, 3-methylbiphenyl-4-yl group, 2'-methylbiphenyl-4- yl group, 4'-methylbiphenyl-4-yl group, 2,2'-dimethylbiphenyl-4-yl group, 6-methylbiphenyl-3-yl group, 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.

Ar ¹ and Ar ² are preferably each independently a phenyl group or a biphenylyl group, and more preferably a phenyl group or a 4-biphenylyl group, because the triazine compound (1) has excellent electron transport properties.

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

The polycyclic aromatic group is preferably a bicyclic, tricyclic or tetracyclic polycyclic aromatic group in terms of ease of synthesis of the triazine compound (1). Polycyclic aromatic groups are more preferred.

The polycyclic aromatic group is a hydrocarbon-based aromatic group, a nitrogen-containing 6-membered ring aromatic group or a chalcogen-containing group in that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device. An aromatic group is preferred.

Examples of aromatic hydrocarbon groups include naphthyl, phenanthryl, anthryl, pyrenyl, fluorenyl, benzofluorenyl, triphenylenyl and fluoranthenyl groups. The aromatic hydrocarbon is preferably a phenanthryl group, a fluorenyl group, an anthryl group, or a triphenylenyl group in that the triazine compound (1) contributes to the formation of a higher-performance organic electroluminescent device. ,9-dimethylfluoren-2-yl group and 2-triphenylenyl group are more preferred.

Examples of nitrogen-containing aromatic groups include azanaphthyl group, diazanaphthyl group, benzo[b]quinolyl group, benzo[c]quinolyl group, benzo[f]quinolyl group, benzo[g]quinolyl group, and benzo[h]quinolyl group. , phenazinyl group, phenanthrolinyl group, azapyrenyl group, diazapyrenyl group, azatriphenylenyl group, diazatriphenylenyl group and the like. From the viewpoint 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 1,10-phenanth. Lorinyl groups are more preferred.

Examples of chalcogen-containing aromatic groups include benzothiophenyl, benzofuranyl, dibenzothiophenyl, dibenzofuranyl, benzonaphthofuranyl, benzonaphthothiophenyl, xanthenyl, and benzoxanthenyl groups. be done. The chalcogen-containing aromatic group is preferably a dibenzofuranyl group in terms of ease of synthesis of the triazine compound (1).

[About ^Ar4 ]
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 selected from the group consisting of a methyl group and a phenyl group.

Azaphenyl group, diazaphenyl group, azanaphthyl group or diazanaphthyl group includes, for example, pyridyl group, pyrazyl group, pyrimidyl group, quinolyl group, isoquinolyl group, naphthyridinyl group, quinoxalinyl group or quinazolinyl group.

In that the triazine compound (1) contributes to the formation of higher performance organic electroluminescent devices, Ar ⁴
a phenyl group, or
An azaphenyl group optionally substituted with one or more selected from the group consisting of a methyl group and a phenyl group is preferred.
More preferably Ar ⁴ is a pyridyl group.

[About ^X1 ]
X ¹ is a 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group, 2,6-naphthylene group or 2,7- represents a naphthylene group.

X ¹ is preferably a phenylene group, such as a 1,3-phenylene group or a 1,4-phenylene group, in that the triazine compound (1) contributes to the formation of an organic electroluminescent device with higher performance. It is more preferable to have

[About ^X2 ]
X2 represents a phenylene group, a naphthylene group, an ^azaphenylene group, a diazaphenylene group, an azanaphthylene group or a diazanaphthylene group.

Examples of X ² include 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 2,3-pyridylene group, 2,4-pyridylene group, 2,5-pyridylene group, 2 ,6-pyridylene group, 2,4-pyrimidylene group, 2,5-pyrimidylene group, 2,5-pyrazylene group, 1,2-naphthylene group, 1,3-naphthylene group, 1,4-naphthylene group, 1, 5-naphthylene group, 1,6-naphthylene group, 1,7-naphthylene group, 1,8-naphthylene group, 2,3-naphthylene group, 2,4-naphthylene group, 2,5-naphthylene group, 2,6 -naphthylene group, 2,7-naphthylene group, 2,8-naphthylene group, 2,3-quinolylene group, 2,4-quinolylene group, 2,5-quinolylene group, 2,6-quinolylene group, 2,7- quinolylene group, 2,8-quinolylene group, 3,4-quinolylene group, 3,5-quinolylene group, 3,6-quinolylene group, 3,7-quinolylene group, 3,8-quinolylene group, 4,5-quinolylene group group, 4,6-quinolylene group, 4,7-quinolylene group, 4,8-quinolylene group, 5,8-quinolylene group, 2,3-quinoxalylen group, 2,5-quinoxalylen group, 2,6-quinoxalylen group , 2,4-quinazolylene group, 2,5-quinazolylene group, and 2,6-quinazolylene group.

X ² is preferably a phenylene group, such as a 1,2-phenylene group or a 1,4-phenylene group, in that the triazine compound (1) contributes to the formation of an organic electroluminescent device with higher performance. It is more preferable to have

[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 in that the triazine compound (1) contributes to the formation of an organic electroluminescent device with higher performance.

[About q]
q represents 0, 1 or 2; However, when p is 2, two X ² may be the same or different.
q is more preferably 0 or 1 from the viewpoint of easy synthesis of the triazine compound (1).

[Preferred Embodiment of Triazine Compound (1)]
Ar ¹ and Ar ² are phenyl groups;
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.

[Specific examples of triazine compound (1)]
Specific examples of the triazine compound (1) include (1-1) to (1-93) below, but the present disclosure is not limited thereto. A compound represented by 1-1 or 1-46 is preferable as the triazine compound (1) in terms of good performance as an electron transport material in an organic electroluminescent device.

Next, a method for producing triazine compound (1) will be described.
Triazine compound (1) can be produced by the method shown in the following synthetic route.
That is, in the method for producing a triazine compound according to one aspect of the present disclosure, a triazine intermediate represented by formula (2) and a compound represented by formula (3) are subjected to a coupling reaction in the presence of a palladium catalyst. Including letting:

During the ceremony,
Ar ¹ , Ar ² , Ar ³ , Ar ⁴ , 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 represents ^ZnZi , ^MgZ2 , Sn(Z3) ³ , or B ₍ ^OZ4 ) ₂ ;
Z ¹ and Z ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Z ³ is the same or different and represents 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, and two Z ⁴ may be the same or different The two (OZ ⁴ ) groups are united may form a ring together with the boron atom.

Among these, M is preferably B(OZ ⁴ ) ₂ in terms of easy synthesis of the triazine compound (1).

ZnZ ¹ and MgZ ² are not particularly limited, but can be exemplified by ZnCl, ZnBr, ZnI, MgCl, MgBr and MgI.
Examples of Sn(Z ³ ) ₃ include, but are not limited to, Sn(Me) ₃ and Sn(Bu) ₃ .
B(OZ ⁴ ) ₂ is not particularly limited, but examples include 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, examples of B(OZ ⁴ ) ₂ when two (OZ ⁴ ) groups are united to form a ring together with a boron atom are 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 that the yield is good.

The coupling reaction in the synthetic route is a step of reacting a triazine compound represented by formula (2) with a halogen compound represented by formula (3) in the presence of a palladium catalyst to produce triazine compound (1). is. As for the synthesis route, the desired product can be obtained in good yield by applying reaction conditions for 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 the synthetic route, it is preferably carried out in the presence of a base. .
A triazine compound used in the coupling reaction can be produced, for example, according to the method disclosed in WO2017/052259. Moreover, you may use a commercial item.
A halogenated compound used in the coupling reaction can be produced, for example, according to Korean Patent Publication No. 2015/122343. Moreover, you may use a commercial item. Although there is no particular limitation on the molar equivalent of the halogenated compound to be used, it is preferable to use 0.5 to 3.0 molar equivalents relative to the triazine compound from the viewpoint of good reaction yield.

Groups represented by Y include a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group and an iodine atom. A trifluoromethanesulfonyloxy group is preferable in that the yield of the triazine compound (1) is good.

The palladium catalyst that can be used in the synthetic route is not particularly limited, but specifically,
palladium salts such as palladium chloride, palladium acetate, palladium trifluoroacetate, palladium nitrate;
complex compounds such as π-allylpalladium chloride dimer, palladium acetylacetonato, tris(dibenzylideneacetone)dipalladium, bis(dibenzylideneacetone)palladium, dichlorobis(acetonitrile)palladium, dichlorobis(benzonitrile)palladium; and
Dichlorobis(triphenylphosphine)palladium, Tetrakis(triphenylphosphine)palladium, Dichloro[1,1'-bis(diphenylphosphino)ferrocene]palladium, Bis(tri-t-butylphosphine)palladium, Bis(tricyclohexylphosphine) Palladium complexes having tertiary phosphines as ligands such as palladium and dichlorobis(tricyclohexylphosphine)palladium;
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 complex compound. Tertiary phosphines that can be used at this time 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, 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-xylyl)phosphine, (±)-2,2'-bis(diphenylphosphino )-1,1′-binaphthyl, 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl and the like.

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 as a child is more preferred.

The molar ratio of the tertiary phosphine and the palladium salt or complex compound is preferably in the range of 1:10 to 10:1, more preferably in the range of 1:2 to 3:1 in terms of good yield. preferable. Although the amount of the palladium catalyst used in the synthetic route is not limited, the molar equivalent of the palladium catalyst is preferably in the range of 0.005 to 0.5 molar equivalents with respect to the triazine compound in terms of good yield.

The synthetic route may be carried out by adding a base, and 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; Sodium fluoride and potassium fluoride , metal fluoride salts such as cesium fluoride; metal alkoxides such as sodium methoxide, potassium methoxide, sodium ethoxide, potassium isopropyl oxide, potassium tert-butoxide; and the like. Among them, metal carbonates or metal phosphates are preferable, and potassium carbonate or potassium phosphate is more preferable, because of good reaction yield. Although the amount of the base is not particularly limited, the molar ratio between the base and the triazine compound is preferably in the range of 1:2 to 10:1, more preferably 1:1 to 4:1, from the viewpoint of good reaction yield. is more preferably in the range of

The synthetic route can be carried out in solvents such as water; diisopropyl ether, dibutyl ether, cyclopentyl methyl ether (CPME), tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,4-dioxane, ethers such as dimethoxyethane; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, and tetralin; carbonate esters such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethylmethyl carbonate, and 4-fluoroethylene carbonate; ethyl acetate , butyl acetate, methyl propionate, ethyl propionate, methyl butyrate, gamma-lactone; , N,N',N'-tetramethylurea (TMU), N,N'-dimethylpropyleneurea (DMPU); dimethyl sulfoxide (DMSO); and methanol, ethanol, isopropyl alcohol, butanol, octanol, Alcohols such as benzyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 2,2,2-trifluoroethanol; There are no particular restrictions on the amount of solvent used. Among these, water, ether, amide, alcohol, or a mixed solvent thereof is preferable, and a mixed solvent of THF and water is more preferable, because the reaction yield is good.

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 is obtained by usual work-up after completion of the reaction. If necessary, it may be purified by recrystallization, column chromatography, sublimation, preparative HPLC, or the like.

The triazine compound (1) can be used, for example, for organic electronic devices such as organic electroluminescence devices and photoelectric devices.

<Materials for Organic Electroluminescent Devices>
A material for an organic electroluminescence device according to one aspect of the present disclosure contains a triazine compound (1).
Triazine compound (1) can be used, for example, as an electron transport material for organic electroluminescence devices. The organic electroluminescent element material containing the triazine compound (1) exhibits high luminous efficiency and long life characteristics at a high level, and contributes to the production of organic electroluminescent elements that can be used in various applications.

<Organic electroluminescent element>
An organic electroluminescence device containing the triazine compound (1) will be described below.
The organic electroluminescent device contains triazine compound (1).

The configuration of the organic electroluminescent device is not particularly limited, but includes, for example, 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

Although the triazine compound (1) may be contained in any of the above layers, it is preferred 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. It is preferably contained in one or more selected layers.

Therefore, in the case of the structures shown in (i) to (v) above, the triazine compound (1) is preferably 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 electroluminescence device will be described in more detail with reference to FIG. 1, taking the above configuration (v) as an example.

The organic electroluminescence device 100 shown in FIG. 1 has a so-called bottom emission type device configuration, but the organic electroluminescence device is not limited to the bottom emission type device configuration. That is, the organic electroluminescent device may have other known device configurations such as top emission type.

FIG. 1 is a schematic cross-sectional view showing an example of a lamination structure of an organic electroluminescence device containing a triazine compound (1).

The organic electroluminescent device 100 comprises 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 of these layers may be omitted, or conversely, other layers may be added. For example, a hole-blocking layer may be provided between the light-emitting layer 5 and the electron-transporting layer 6, the hole-injecting layer 3 may be omitted, and the hole-transporting layer 4 may be provided directly on the anode 2. good too.

Further, a single layer having the functions of a plurality of layers, such as an electron injection/transport layer having both the function of an electron injection layer and the function of an electron transport layer in a single layer. may be provided instead of. Further, for example, each of the single-layer hole transport layer 4 and the single-layer electron transport layer 6 may be composed of a plurality of layers.

<<Layer containing triazine compound (1)>>

In the structural example shown in FIG. 1, the organic electroluminescence 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 . The electron transport layer 6 preferably contains the triazine compound (1). In addition, the triazine compound (1) may be contained in a plurality of layers included in the organic electroluminescence device.

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

[Substrate 1]
The substrate 1 is not particularly limited as long as it is a substrate that a person skilled in the art normally uses for the part, and examples thereof include a glass plate, a quartz plate, a plastic plate, and a plastic film. Among these, a glass plate, a quartz plate, and a transparent plastic film are preferable.

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

In addition, in the case of a configuration in which emitted light is extracted from the substrate 1 side, the substrate 1 is transparent to the wavelength of the emitted light.

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

Materials for the anode include metals, alloys, electrically conductive compounds, and mixtures thereof having a large work function (for example, 4 eV or more). Specific examples of materials for the anode include metals such as Au; conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ and ZnO.

For organic electroluminescent devices configured such that emitted light is extracted through the anode, the anode is formed of a conductive transparent material that is transparent or substantially transparent to the emitted light.

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

The hole-injecting layer 3 and the hole-transporting layer 4 have a function of transferring holes injected from the anode to the light-emitting layer. , more holes are injected into the light-emitting layer 5 at a lower electric field.

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 transferred to the interface between the light emitting layer 5 and the hole injection layer 3 and/or the hole transport layer 4. The barrier of electrons present in the hole-injecting layer 3 and/or the hole-transporting layer 4 is suppressed from leaking. As a result, the electrons are accumulated at the interface in the light-emitting layer 5, resulting in an effect such as an improvement in light-emitting efficiency, and an organic electroluminescence device with excellent light-emitting performance can be obtained.

A material for the hole injection layer 3 and the hole transport layer 4 has at least one of hole injection properties, hole transport properties, and electron blocking properties. Materials for the hole injection layer 3 and the hole transport layer 4 may be either organic compounds or inorganic substances.

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 (especially thiophene oligomers), porphyrin compounds, aromatic tertiary amine compounds , styrylamine compounds, and the like.

Among these, porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds are preferred, and aromatic tertiary amine compounds are particularly preferred, from the viewpoint of good performance of the organic electroluminescent device.

Specific examples of aromatic tertiary amine compounds and styrylamine compounds 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-tolylamino 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]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), 4,4',4''-tris[N-(m-tolyl)-N-phenylamino]triphenylamine (MTDATA) and the like.

Inorganic compounds such as p-type-Si and p-type-SiC can also be given as examples of materials for the hole injection layer 3 and the hole transport layer 4 .

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 laminated structure made up of multiple layers of 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 .

Materials for the light-emitting layer 5, that is, light-emitting materials, include phosphorescent light-emitting materials, fluorescent light-emitting materials, and thermally activated delayed fluorescent light-emitting materials. In the light-emitting layer 5, electron-hole pairs recombine, resulting in light emission.

Emissive layer 5 may consist of a single small molecule material or a single polymeric material, but more commonly consists of a host material doped with a guest compound. Emission comes primarily from dopants and can have any color.

Host materials include, for example, 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-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 can be mentioned.

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, and indenoperylenes. derivatives, bis(azinyl)amine boron compounds, bis(azinyl)methane compounds, carbostyril compounds, boron compounds, cyclic amine compounds and the like. The fluorescent dopant may be a combination of two or more selected from these.

Examples of phosphorescent dopants include metal complexes such as iridium, platinum, palladium and osmium.

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](acetylacetonato)iridium(III), Ir(PPy) ₃ (tris(2-phenylpyridine)iridium(III)), FIrPic (bis(3,5-difluoro -2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium (III))) and the like.

Moreover, 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). Thereby, the luminous efficiency of the organic electroluminescence device 100 can be further improved.

The light-emitting layer may have a single-layer structure composed of five, one, or two or more materials, or may have a laminated structure composed of multiple layers having the same composition or different compositions.

[Electron transport layer 6]
An electron transport layer 6 is provided between the light emitting layer 5 and the electron injection layer 7 .

The electron transport layer 6 has a function of transmitting electrons injected from the cathode 8 to the light emitting layer. By interposing the electron-transporting 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.

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 selected from conventionally known electron transport materials.

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

Conventionally known electron-transporting materials include alkali metal compounds, alkaline earth metal compounds, transition metal compounds, zinc group element compounds, and earth metal compounds. Examples of alkali metal compounds, alkaline earth metal compounds, transition metal compounds, zinc group element compounds, and earth metal compounds include lithium 8-hydroxyquinolinate (Liq), bis(8-hydroxyquinolinate)zinc, Bis(8-hydroxyquinolinato) copper, bis(8-hydroxyquinolinato) manganese, tris(8-hydroxyquinolinato) aluminum, tris(2-methyl-8-hydroxyquinolinato) aluminum, tris( 8-hydroxyquinolinato)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-cresolato) gallium, bis(2-methyl-8-quinolinato)-1-naphtholato aluminum, bis(2-methyl-8-quinolinato)-2-naphtholato gallium, etc. chelate-type aryloxides and the like.

The electron transport layer 6 may have a single layer structure made of one or more materials, or may have a laminated structure made up of a plurality of layers having the same composition or different compositions.

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

[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 interposing an 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.

Materials for the electron injection layer 7 include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, frelenylidenemethane, anthraquinodimethane, anthrone, and the like. organic compounds.

Materials for the electron injection layer 7 include various oxides such as SiO ₂ , AlO, SiN, SiON, AlON, GeO, LiO, LiON, TiO, TiON, TaO, TaON, TaN, LiF, C and Yb, and fluorine. Inorganic compounds such as oxides, nitrides, and oxynitrides are also included.

[Cathode 8]
A cathode 8 is provided on the electron injection layer 7 . In the case of an organic electroluminescence device configured so that only light emitted through the anode 8 is taken out, the cathode 8 can be made of any conductive material.

Examples of materials for the cathode 8 include metals with a small work function (hereinafter also referred to as electron-injecting metals), alloys, electrically conductive compounds, and mixtures thereof. Here, a metal with a small work function is, for example, a metal of 4 eV or less.

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 (Al ₂ O ₃ ) mixtures, indium, lithium/aluminum mixtures, rare earth metals, and the like.

Among these, mixtures of electron-injecting metals and second metals, which are stable metals with a larger work function value, such as magnesium/silver mixtures, magnesium /aluminum mixtures, magnesium/indium mixtures, aluminum/aluminum oxide _{( Al2O3} ) mixtures, lithium/aluminum mixtures, etc. are preferred.

[Method of Forming Each Layer]
Each layer except for 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 a LB (Langmuir-Blodgett method) method. be able to. The material for each layer may be used alone, or if necessary, it may be used together with a material such as a binder resin and a solvent.

The thickness of each layer thus formed is not particularly limited and can be appropriately selected depending on the situation, but is usually in the range of 5 nm to 5 μm.

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 through 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, sputtering, or the like.

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

Incidentally, the layer containing the triazine compound (1) may be formed in combination with the conventionally known electron-transporting material. Therefore, for example, the triazine compound (1) and a conventionally known electron-transporting material may be co-deposited, or a layer of a conventionally known electron-transporting material may be laminated on the layer of the triazine compound (1).

The organic electroluminescence element may be used as a kind of lamp for illumination or as a light source for exposure, a type of projection device for projecting an image onto a screen or the like, or a type of display for directly viewing still images or moving images. You may use it as a device (display).

When the organic electroluminescence element is used as a display device for reproducing moving images, the drive system may be a simple matrix (passive matrix) system or an active matrix system. Further, by using two or more kinds of organic electroluminescent elements having different emission colors, it is possible to produce a full-color display device.

The triazine compound (1) can provide an organic electroluminescence device that is significantly superior in driving voltage and luminous efficiency to conventionally known triazine compounds when used as an electron transport layer.

Therefore, effects such as improvement in drive stability of the organic electroluminescence device and improvement in luminous efficiency are expected. Moreover, the triazine compound (1) has high chemical stability due to its characteristic skeleton, and can contribute to the extension of the life of the organic electroluminescence 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 levels of low-voltage drive, high efficiency, and long life of the device. Further, it is possible to provide an organic electroluminescence device using the triazine compound (1), which can exhibit high efficiency and long life at a high level.

Hereinafter, the present disclosure will be described in more detail based on examples, but the present disclosure should not be construed as being limited by these examples. Commercially available reagents were used.

[ ¹ H-NMR measurement]
Bruker ASCEND 400 (400 MHz; manufactured by BRUKER) or Bruker ULTRASHIELD Plus 400 (400 MHz; manufactured by BRUKER) was used for ¹ H-NMR measurement. ¹ H-NMR was measured using deuterated chloroform (CDCl ₃ ) or deuterated dimethylsulfoxide (DMSO-d ₆ ) as a measurement solvent and tetramethylsilane (TMS) as an internal standard substance.

[Emission characteristic measurement]
The luminous properties of the organic electroluminescence device were evaluated using a luminance meter BM-9 (product name, manufactured by Topcon Technohouse Co., Ltd.) by applying a direct current to the device prepared in each example (described later) in an environment of 25°C. did.

Synthetic Example-1

Under an argon atmosphere, 3-(9-phenanthryl)-5-(3-pyridyl)phenyl trifluoromethanesulfonic acid (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), 2-dicyclohexyl Phosphino-2′,4′,6′-triisopropylbiphenyl (229 mg, 0.48 mmol) was dissolved in tetrahydrofuran (80 mL). A 2M potassium carbonate aqueous solution (12 mL) was added thereto, and the mixture was stirred at 80° C. for 24 hours. After allowing to cool to room temperature, water and methanol were added to suspend, followed by filtration. The residue was washed with water and methanol to give crude product. The crude product was dissolved in chloroform, activated carbon was added and stirred for 30 minutes. After removing the activated carbon by celite filtration, the solvent was distilled off under reduced pressure. The resulting solid is 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) was obtained as a white solid (3.81 g, 75%).

¹ H-NMR (CDCl ₃ ) δ (ppm): 9.04 (d, J = 1.7, 1H), 8.90 (d, J = 8.5 Hz, 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).

Synthesis example-2

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 trifluoromethanesulfonic acid (4.60 g, 9.6 mmol), palladium acetate (54 mg, 0.24 mmol), 2 -Dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (228 mg, 0.48 mmol) was suspended in THF (80 mL). A 2M potassium carbonate aqueous solution (12 mL) was added to this suspension, and the mixture was heated under reflux for 15 hours. After allowing to cool 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) and then recrystallization (toluene) to give the desired 2-[3′-(phenanthren-9-yl)-5′-(pyridine-3 -yl)-(1,1′-biphenyl)-3-yl]-4,6-diphenyl-1,3,5-triazine (compound 1-46) was obtained (4.10 g, 80%).

¹ H-NMR (CDCl ₃ ) δ (ppm): 9.10 (t, J = 1.6 Hz, 1H), 9.05 (dd, J = 2.4, 0.7 Hz, 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).

Reference example-1

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 added. Suspended in 1,4-dioxane (100 mL). A 5M aqueous sodium hydroxide solution (29 mL) was added to this 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 thereto. Sodium sulfate was filtered off, and the filtrate was dried under reduced pressure. The obtained crude product was purified by silica gel column chromatography (chloroform/ethyl acetate=20/1) to obtain the target 3-chloro-5-(phenanthren-9-yl)phenol as a brown solid (14. 2g, 97%).

¹ H-NMR (CDCl ₃ ) δ (ppm): 8.77 (d, J = 8.2 Hz, 1H), 8.72 (d, J = 8.2 Hz, 1H), 7.88-7.91 (m, 2H), 7.60-7.71 (m, 4H), 7.54-7.58 (m, 1H), 7.12 (t, J=1.7Hz, 1H), 6.96 (t, J=1.7 Hz, 1 H), 6.89-6.91 (m, 1 H), 5.28 (brs, 1 H).

Reference example-2

Under an argon atmosphere, 3-chloro-5-(9-phenanthryl)phenol (6.60 g, 22 mmol), bis(pinacolato)diboron (11.0 g, 43 mmol), and tris(dibenzylideneacetone) dipalladium (496 mg, 0.5 mmol). 54 mmol), 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (1.03 g, 2.2 mmol), potassium acetate (8.50 g, 87 mmol) were suspended in dioxane (216 mL), Stir at 110° C. for 24 hours. After allowing to cool, the resulting mixture was extracted with chloroform and washed with saturated brine. After concentrating the organic layer, purification by silica gel column chromatography was performed to give 3-(phenanthren-9-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl ) A white solid of phenol was obtained (8.50 g, 99% yield).

¹ H-NMR (CDCl ₃ ) 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 ).

Reference example - 3

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), tetrakis(triphenylphosphine)palladium (496 mg, 0.43 mmol) were dissolved in tetrahydrofuran (214 mL). A 2M aqueous sodium carbonate solution (43 mL) was added thereto, and the mixture was stirred at 80° C. overnight. After cooling to room temperature, chloroform was added to suspend 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%).

¹ H-NMR (DMSO-d ₆ ) δ (ppm): 9.96 (br, 1H), 8.87-8.96 (m, 3H), 8.58 (dd, J = 4.7, 1 .5 Hz, 1 H), 8.12 (dt, J=8.0, 1.9 Hz, 1 H), 8.05 (d, J=7.8, 1 H), 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=1.9 Hz, 1 H), 7.00 (s, 1 H).

Reference example - 3

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 was added thereto. (3.6 mL, 21 mmol) was added dropwise and stirred overnight at room temperature. After completion of the reaction, the resulting mixture was extracted with chloroform and washed with water and saturated brine. After concentrating the organic layer, purification by silica gel chromatography was performed to obtain a white solid of 3-(9-phenanthryl)-5-(3-pyridyl)phenyltrifluoromethanesulfonic acid (6.7 g, 77%).

¹ H-NMR (CDCl ₃ ) δ (ppm): 8.92 (d, J = 2.4, 1H), 8.82 (d, J = 8.2 Hz, 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).

Reference example - 4

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

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

[Evaluation as electron transport layer 6]
Device example-1 (see Fig. 2)
(Preparation of substrate 1 and anode 2)
As a substrate 1 having an anode 2 on its surface, a glass substrate with an ITO transparent electrode, in which an indium-tin oxide (ITO) film (thickness: 110 nm) with a width of 2 mm was patterned in stripes, was prepared. Then, after washing the substrate with isopropyl alcohol, the surface was treated by ozone ultraviolet washing.

(Preparation for vacuum deposition)
Each layer was vacuum-deposited on the surface-treated substrate after cleaning by a vacuum deposition method to laminate each layer.
First, the glass substrate was introduced into a vacuum 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. In addition, each organic material was formed into a film by a resistance heating method.

(Preparation 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-fluorene -2-amine and 1,2,3-tris[(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane were deposited at a ratio of 99:1 (mass ratio) to form a 10 nm film. , hole-injection 3 were made. The deposition rate was 0.1 nm/sec.

(Preparation 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-fluorene-2 -Amine was deposited at a rate of 0.2 nm/sec to a thickness of 85 nm to prepare the first hole transport layer 41 .

(Preparation of 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 5 nm film. , a second hole transport layer 42 was produced.

(Preparation of light-emitting layer 5)
3-(10-phenyl-9-anthryl)-dibenzofuran and 2,7-bis[N,N-di-(4-tertbutylphenyl)]amino-bisbenzofurano-9,9′-spirofluorene purified by sublimation and were deposited at a ratio of 95:5 (mass ratio) to a thickness of 20 nm to prepare a light-emitting layer 5 . The deposition rate was 0.1 nm/sec.

(Preparation 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- A film of triazine having a thickness of 6 nm was formed at a rate of 0.05 nm/sec to prepare a hole blocking layer 9 .

(Preparation of electron transport layer 6)
2-[3′-(phenanthren-9-yl)-5′-(pyridin-3-yl)-(1,1′-biphenyl)-4-yl]-4,6 synthesized in Synthesis Example-1 -Diphenyl-1,3,5-triazine (compound 1-1) and 8-hydroxyquinolinolatolithium (hereinafter, Liq) were deposited at a ratio of 50:50 (mass ratio) to form a 25 nm film, and an electron transport layer 6 was formed. made. The deposition rate was 0.15 nm/sec.

(Preparation of electron injection layer 7)
An electron injection layer 7 was produced by depositing Liq to a thickness of 2 nm at a rate of 0.02 nm/sec.

(Preparation of cathode 8)
Finally, a metal mask was placed so as to be perpendicular to the ITO stripes (anode 2) on the substrate 1, and a cathode 8 was formed. The cathode was formed by depositing silver/magnesium (mass ratio 1/10) and silver in this order to 80 nm and 20 nm, respectively, to form a two-layer structure. The deposition rate of silver/magnesium was 0.5 nm/second, and the deposition rate of silver was 0.2 nm/second.

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

Element example-2
In Device Example-1, 2-[3′-(phenanthren-9-yl)-5′-(pyridin-3-yl)-(1,1) synthesized in Synthesis Example-2 was added to the electron transport layer 6 '-Biphenyl)-3-yl]-4,6-diphenyl-1,3,5-triazine (compound 1-46) and Liq at a ratio of 50:50 (mass ratio) to form a 25 nm film (film formation rate: 0 .15 nm/sec), except that compound A-49 and Liq were deposited at a ratio of 50:50 (mass ratio) to form a 25 nm film (film formation rate: 0.15 nm/sec). An organic electroluminescence device was fabricated by the method.
Element reference example-1

In Device Example-1, the electron transport layer 6 contains 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 at a ratio of 50:50 (mass ratio) to form a 25 nm film (film formation rate 0.15 nm / sec) Instead of , ETL-1 and Liq were deposited at a ratio of 50:50 (mass ratio) to form a 25 nm film (film formation rate: 0.15 nm/sec). .

A direct current was applied to the produced organic electroluminescence device, and the luminous properties were evaluated according to the method described in the measurement of luminous properties.

As light emission characteristics, the current efficiency (cd/A) was measured when a current density of 10 mA/cm ² was applied, and the life of the element during continuous lighting was measured. The device life was measured by measuring the luminance decay time during continuous lighting when the device was driven at an initial luminance of 1000 cd/m ² , and measuring the time required for the luminance (cd/m ² ) to decrease by 5%. The values of current efficiency (cd/A) and lifetime are expressed as relative values when the device reference example-1 is set to 100. Table 1 shows the results.

1. Substrate 2 . Anode 3 . hole injection layer 4 . hole transport layer 5 . Light-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 element

Claims (19)

Triazine compound represented by formula (1):

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group or a naphthylphenyl group, and these groups are selected from the group consisting of a fluorine atom, a methyl group and a cyano group. optionally substituted by one or more substituents;
Ar ³ represents a polycyclic aromatic group optionally substituted with one or more 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 selected from the group consisting of a methyl group and a phenyl group;
X ¹ is a 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group, 2,6-naphthylene group or 2,7- represents a naphthylene group;
X2 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;
provided that 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. The triazine compound according to claim 1, wherein Ar ¹ and Ar ² are each independently a phenyl group or a biphenylyl group. 3. The triazine compound according to claim 1 or 2, wherein the polycyclic aromatic group is a bicyclic, tricyclic or tetracyclic polycyclic aromatic group. 4. The triazine compound according to any one of claims 1 to 3, wherein said polycyclic aromatic group is a tricyclic or tetracyclic polycyclic aromatic group. 5. The triazine compound according to any one of claims 1 to 4, wherein the polycyclic aromatic group is a hydrocarbon aromatic group, a nitrogen-containing 6-membered ring aromatic group or a chalcogen-containing aromatic group. the hydrocarbon aromatic group is a 9-phenanthryl group, a 9,9-dimethylfluoren-2-yl group or a 2-triphenylenyl group;
the nitrogen-containing 6-membered ring aromatic group is a 1,10-phenanthrolinyl group,
6. The triazine compound according to claim 5, wherein the chalcogen-containing aromatic group is a dibenzofuranyl group. ^Ar4 is
a phenyl group, or
7. The triazine compound according to any one of claims 1 to 6, which is an azaphenyl group optionally substituted with one or more selected from the group consisting of a methyl group and a phenyl group. 8. The triazine compound according to any one of claims 1 to 7, wherein ^Ar4 is a pyridyl group. 9. The triazine compound according to any one of claims 1 to 8, wherein X ¹ is a 1,3-phenylene group or a 1,4-phenylene group. 10. ^The triazine compound according to any one of claims 1 to 9, wherein X2 is a phenylene group. 11. The triazine compound according to any one of claims 1 to 10, wherein p is 1. 12. The triazine compound of any one of claims 1-11, wherein q is 0 or 1. Ar ¹ and Ar ² are phenyl groups;
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;
2. The triazine compound of claim 1, wherein p is 1. A triazine compound represented by formula (1), comprising coupling a triazine intermediate represented by formula (2) with a compound represented by formula (3) in the presence of a palladium catalyst. Production method:

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group, a naphthyl group, a phenylnaphthyl group or a naphthylphenyl group, and these groups are selected from the group consisting of a fluorine atom, a methyl group and a cyano group. optionally substituted by one or more substituents;
Ar ³ represents a polycyclic aromatic group optionally substituted with one or more 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 selected from the group consisting of a methyl group and a phenyl group;
X ¹ is a 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group, 2,6-naphthylene group or 2,7- represents a naphthylene group;
X2 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;
provided that when p is 2, two X ¹ may be the same or different;
q represents 0, 1 or 2;
provided that when q is 2, two X ² may be the same or different;
M represents ^ZnZi , ^MgZ2 , Sn(Z3) ³ , or B ₍ ^OZ4 ) ₂ ;
Z ¹ and Z ² each independently represent 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, and two Z ⁴ may be the same or different;
the two (OZ ⁴ ) groups may together form a ring together with the boron atom;
Y represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group or an iodine atom. 15. The method for producing a triazine compound according to claim 14, wherein M is B( ^OZ4 ) ₂ . The production method according to claim 14 or 15, wherein the palladium catalyst is a palladium catalyst having a tertiary phosphine as a ligand. The production method according to claim 16, wherein the tertiary phosphine is triphenylphosphine or 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl. A material for an organic electroluminescence device, comprising the triazine compound according to any one of claims 1 to 13. An organic electroluminescence device containing the triazine compound according to any one of claims 1 to 13.

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