JP7361564B2 - Triazine compounds containing Group 14 elements - Google Patents

Description

The present disclosure relates to a triazine compound having a Group 14 element, a method for producing the same, and an organic electroluminescent device.

Organic electroluminescent devices have begun to be put into practical use mainly for small mobile applications. However, performance improvement is essential for further popularization and expansion of applications, and in particular, materials with high luminous efficiency characteristics are required to reduce power consumption.

Here, Patent Document 1 discloses a triazine compound that is a material for an organic electroluminescent device that can reduce driving voltage with high efficiency.

Patent No. 5812583

There is a strong demand from the market for expanding the applications of organic electroluminescent devices. For this reason, materials with particularly high luminous efficiency are required.
Here, although the triazine compound according to Patent Document 1 sufficiently satisfies the above characteristics at a predetermined level, there is a need to develop a material having even higher luminous efficiency.

Accordingly, one embodiment of the present disclosure is directed to providing a triazine compound and a method for producing the same that contribute to the formation of an organic electroluminescent device that exhibits high luminous efficiency.
Further, another aspect of the present disclosure is directed to providing an organic electroluminescent device using the above triazine compound and having high luminous efficiency.

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

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
hydrogen atom,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
Represents a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring;
Ar ¹ , Ar ² and Ar ³ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R are the same or different,
an alkyl group having 1 to 6 carbon atoms,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, which may be substituted with an alkyl group having 1 to 4 carbon atoms,
A nitrogen-containing aromatic group having 4 to 14 carbon atoms, consisting only of a 6-membered ring which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group, or
represents a heterocyclic group having 4 to 14 carbon atoms, in which the heteroatom which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group is a Group 16 element;
Two adjacent R's may each be combined to form a 5- or 6-membered ring containing Z to which the two Rs are bonded;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p represents 0, 1 or 2.

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

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
hydrogen atom,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
Represents a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring;
Ar ¹ , Ar ² and Ar ³ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R are the same or different,
an alkyl group having 1 to 6 carbon atoms,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, which may be substituted with an alkyl group having 1 to 4 carbon atoms,
A nitrogen-containing aromatic group having 4 to 14 carbon atoms, consisting only of a 6-membered ring which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group, or
represents a heterocyclic group having 4 to 14 carbon atoms, in which the heteroatom which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group is a Group 16 element;
Two adjacent R's may each be combined to form a 5- or 6-membered ring containing Z to which the two Rs are bonded;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p' represents 1 or 2;
M ¹ represents ZnY ¹ , MgY ² , Sn(Y ³ ) ₃ or B(OY ⁴ ) ₂ ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ are the same or different and represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group;
The two (OY ⁴ ) groups may be combined to form a ring with the boron atom to which the two (OY ⁴ ) groups are bonded;
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 formula (1b) according to another aspect of the present disclosure involves a coupling reaction between a compound represented by formula (4) and a compound represented by formula (5). Including:

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
hydrogen atom,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
Represents a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring;
Ar ¹ , Ar ² and Ar ³ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R are the same or different,
an alkyl group having 1 to 6 carbon atoms,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, which may be substituted with an alkyl group having 1 to 4 carbon atoms,
A nitrogen-containing aromatic group having 4 to 14 carbon atoms, consisting only of a 6-membered ring which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group, or
represents a heterocyclic group having 4 to 14 carbon atoms, in which the heteroatom which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group is a Group 16 element;
Two adjacent R's may each be combined to form a 5- or 6-membered ring containing Z to which the two Rs are bonded;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p'' represents 1 or 2;
^X2 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 ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ are the same or different and represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group;
The two (OY ⁴ ) groups may be combined to form a ring together with the boron atom to which the two (OY ⁴ ) groups are bonded.

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

According to one aspect of the present disclosure, it is possible to provide a triazine compound that contributes to the production of an organic electroluminescent device that exhibits high luminous efficiency, and a method for producing the triazine compound.
According to other aspects of the present disclosure, it is possible to provide an organic electroluminescent device with high luminous efficiency.

1 is a schematic cross-sectional view showing an example of a stacked structure of an organic electroluminescent element according to one embodiment of the present disclosure. FIG. 3 is a schematic cross-sectional view showing another example of a stacked structure of an organic electroluminescent device according to one embodiment of the present disclosure (structure of device example-1).

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

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
hydrogen atom,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
Represents a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring;
Ar ¹ , Ar ² and Ar ³ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R are the same or different,
an alkyl group having 1 to 6 carbon atoms,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, which may be substituted with an alkyl group having 1 to 4 carbon atoms,
A nitrogen-containing aromatic group having 4 to 14 carbon atoms, consisting only of a 6-membered ring which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group, or
represents a heterocyclic group having 4 to 14 carbon atoms, in which the heteroatom which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group is a Group 16 element;
Two adjacent R's may each be combined to form a 5- or 6-membered ring containing Z to which the two Rs are bonded;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p represents 0, 1 or 2.

In a triazine compound having the structure shown in formula (1), the present inventors increased the molecular volume by introducing a Group 14 element having a substituent into an appropriate position within the molecule, and It is assumed that the above problems can be solved by this effect.

Hereinafter, the triazine compound (hereinafter also simply referred to as triazine compound (1)) according to one embodiment of the present disclosure will be described in more detail.
The triazine compound (1) is represented by formula (1a), (1b), (1c), (1d), (1e), (1f), (1g), (1h), (1i), or (1j). be done.

In the formula, Ar ¹ , Ar ² , Ar ³ , R, Z, L and p have the same definitions as in formula (1) above.

A compound represented by formula (1a), (1b), (1c), (1d), or (1e) in that the triazine compound (1) contributes to the formation of a higher-performance organic electroluminescent device is preferable, and a compound represented by formula (1a), formula (1b), or (1c) is particularly preferable.
Also, among the compounds represented by formula (1a), formula (1b), or (1c), it is particularly preferable that the compound represented by formula (11a), formula (11b), or formula (11c) preferable.

In the formula, Ar ¹ , Ar ² , Ar ³ , R, Z, and L have the same definitions as in formula (1) above.
q represents 0 or 1.

The definitions of Ar ¹ , Ar ² , Ar ³ , R, L, Z and p in the triazine compound (1) will be explained.

[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, an alkyl group having 1 to 4 carbon atoms, and a phenyl group.

Further, since the triazine compound (1) has excellent electron transport properties, it is preferable that Ar ¹ and Ar ² are each independently a phenyl group or a biphenylyl group.
Ar ¹ and Ar ² are preferably the same group in terms of easy synthesis of the triazine compound (1).

[About Ar ³ ]
Ar ³ is
(i) Hydrogen atom,
(ii) a monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
(iii) Represents a nitrogen-containing heterocyclic group having 4 to 14 carbon atoms.
Ar ³ may be substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group.

(ii) Aromatic hydrocarbon group Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, biphenylyl group, phenanthryl group, anthryl group, pyrenyl group, fluorenyl group, benzofluorenyl group, triphenylenyl group, An example is an oranthenyl group. These groups may be substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group. The alkyl group having 1 to 4 carbon atoms may be a linear, branched, or cyclic alkyl group, and specifically includes a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, and a cycloalkyl group. Examples include propyl group, butyl group, 2-butyl group, and tert-butyl group.

(iii) Nitrogen-containing heterocyclic group Examples of the nitrogen-containing heterocyclic group include a pyridyl group, a piperidyl group, a benzo[b]quinolyl group, a phenylpyridyl group, a carbazolyl group, and the like. These groups may be substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group. The alkyl group having 1 to 4 carbon atoms may be a linear, branched, or cyclic alkyl group, and specifically includes a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, and a cycloalkyl group. Examples include propyl group, butyl group, 2-butyl group, and tert-butyl group.

In that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device, Ar ³
hydrogen atom, or
Unsubstituted or substituted with a methyl group,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
Preferably, it is a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring,
Furthermore, it is particularly preferable that Ar ³ is a hydrogen atom, a phenyl group, a biphenyl group, a naphthyl group, a phenanthrenyl group, a dimethylfluorenyl group, a pyridyl group, a dimethylpyridyl group, or a phenylpyridyl group.

[About R]
R are the same or different,
(i) an alkyl group having 1 to 6 carbon atoms,
(ii) a monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms;
(iii) a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting only of a 6-membered ring which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group, or
(iv) represents a heterocyclic group having 4 to 14 carbon atoms in which the heteroatom which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group is a Group 16 element;
Here, two adjacent Rs may each be combined to form a 5- or 6-membered ring containing Z to which the two Rs are bonded.

(i) Alkyl group The alkyl group having 1 to 6 carbon atoms may be, for example, a linear, branched, or cyclic alkyl group, specifically a methyl group, an ethyl group, a propyl group, or a 2-methyl group. Examples include propyl group, isopropyl group, cyclopropyl group, butyl group, 2-butyl group, tert-butyl group, and cyclobutyl group. R is preferably a methyl group from the viewpoint of easy synthesis of the triazine compound (1).

(ii) Aromatic hydrocarbon group Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, biphenylyl group, phenanthryl group, anthryl group, pyrenyl group, fluorenyl group, benzofluorenyl group, triphenylenyl group, Examples include oranthenyl group. These groups 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 includes a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, and a cycloalkyl group. Examples include propyl group, butyl group, 2-butyl group, and tert-butyl group. From the viewpoint of easy synthesis of the triazine compound (1), R is an unsubstituted aromatic hydrocarbon group having 6 to 14 carbon atoms or an aromatic hydrocarbon group having 6 to 14 carbon atoms substituted with a methyl group. is preferable, and phenyl group or biphenylyl group is particularly preferable.

(iii) Nitrogen-containing aromatic group Examples of the nitrogen-containing heterocycle include a pyridyl group, a piperidyl group, a benzo[b]quinolyl group, a phenylpyridyl group, and a carbazolyl group. These groups may be substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 4 carbon atoms and a phenyl group. The alkyl group having 1 to 4 carbon atoms may be a linear, branched, or cyclic alkyl group, and specifically includes a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, and a cycloalkyl group. Examples include propyl group, butyl group, 2-butyl group, and tert-butyl group. R is preferably a pyridyl group from the viewpoint of easy synthesis of the triazine compound (1).

(iv) Heterocyclic group whose heteroatom is a Group 16 element Examples of the heterocyclic group include a dibenzothiophenyl group, a dibenzofuranyl group, a benzonaphthofuranyl group, and a benzonaphthothiophenyl group. These groups may be substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 4 carbon atoms and a phenyl group. The alkyl group having 1 to 4 carbon atoms may be a linear, branched, or cyclic alkyl group, and specifically includes a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, and a cycloalkyl group. Examples include propyl group, butyl group, 2-butyl group, and tert-butyl group. R is preferably a dibenzofuranyl group or a dibenzothiophenyl group, since the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device.

Here, R is the same or different,
All three Rs may be different from each other,
All three Rs may be the same,
Two of the three R's may be the same and the remaining one may be different from the other two,
Indicates that it is one of the following.

Also, R is the same or different,
an alkyl group having 1 to 4 carbon atoms, or
Unsubstituted or substituted with a methyl group,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms,
A nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring, or
More preferably, it is a C4-C14 heterocyclic group in which the heteroatom is a Group 16 element.

Furthermore, it is particularly preferred that R's are the same or different and are a methyl group, a phenyl group, a biphenylyl group, a naphthyl group, a fluorenyl group, a pyridyl group, a dibenzofuranyl group or a dibenzothiophenyl group.

[About L]
L represents a phenylene group. Examples of the phenylene group include orthophenylene group (1,2-phenylene group), metaphenylene group (1,3-phenylene group), and paraphenylene group (1,4-phenylene group). In that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device, L is a metaphenylene group (1,3-phenylene group) or a paraphenylene group (1,4-phenylene group). is preferable, and a metaphenylene group (1,3-phenylene group) is particularly preferable.

[About Z]
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom. In that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device, Z is preferably a carbon atom, a silicon atom, or a germanium atom, and is a silicon atom or a germanium atom. is particularly preferred.

[About p]
p represents 0, 1 or 2. It is preferable that p is 0 or 1 in that the triazine compound (1) contributes to the formation of a higher performance organic electroluminescent device.

[Specific example of triazine compound (1)]
Specific examples of the triazine compound (1) are not particularly limited, but examples include compounds having structures shown in 1-1 to 1-192 below. Triazine compounds (1) include 1-1, 1-2, 1-28, 1-40, 1-41, 1-66, and 1-74 because of their good performance as electron transport materials in organic electroluminescent devices. , 1-133, 1-148, 1-165, 1-178, or 1-179 are preferred.

Next, a method for producing a triazine compound (hereinafter referred to as a method for producing a triazine compound (1)) according to another aspect of the present disclosure will be described.
Triazine compounds (1a) and (1b) contained in triazine compound (1) can be produced by Step 1 or 2 shown in the following reaction formula.
That is, the method for producing triazine compound (1a) includes coupling a compound represented by formula (2) and a compound represented by formula (3) to a coupling reaction.
Further, the method for producing the triazine compound (1b) includes coupling a compound represented by formula (4) and a compound represented by formula (5) to a coupling reaction.

During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
hydrogen atom,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, or
Represents a nitrogen-containing aromatic group having 4 to 14 carbon atoms consisting of only a 6-membered ring;
Ar ¹ , Ar ² and Ar ³ may each be independently substituted with one or more groups selected from the group consisting of a fluorine atom, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R are the same or different,
an alkyl group having 1 to 6 carbon atoms,
A monocyclic, connected ring, or fused ring aromatic hydrocarbon group having 6 to 20 carbon atoms, which may be substituted with an alkyl group having 1 to 4 carbon atoms,
A nitrogen-containing aromatic group having 4 to 14 carbon atoms, consisting only of a 6-membered ring which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group, or
represents a heterocyclic group having 4 to 14 carbon atoms, in which the heteroatom which may be substituted with an alkyl group having 1 to 4 carbon atoms or a phenyl group is a Group 16 element;
Two adjacent R's may each be combined to form a 5- or 6-membered ring containing Z to which the two Rs are bonded;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p' and p'' each independently represent 1 or 2;
M ¹ represents ZnY ¹ , MgY ² , Sn(Y ³ ) ₃ or B(OY ⁴ ) ₂ ;
M ² represents ZnY ¹ , MgY ² , Sn(Y ³ ) ₃ or B(OY ⁴ ) ₂ ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ are the same or different and represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group;
The two (OY ⁴ ) groups may be combined to form a ring with the boron atom to which the two (OY ⁴ ) groups are bonded;
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 in which triazine compound (2) and compound (3) are subjected to a coupling reaction to produce triazine compound (1a). Here, the coupling reaction is preferably performed in the presence of a catalyst. Step 1 is to obtain the target product in good yield by applying the reaction conditions of general coupling reactions such as Suzuki-Miyaura reaction, Negishi reaction, Tamao-Kumada reaction, Migita-Kosugi-Stille reaction, etc. Can be done. When applying the reaction conditions of the Suzuki-Miyaura reaction 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 formula (2) used in step 1 can be obtained by, for example, the method disclosed in Japanese Patent No. 5312824, or by synthesizing a general organometallic compound from the compound represented by formula (4). It can be synthesized using a reaction (for example, see Angew. Chem. Int. Ed. 2007, 46, 5359-5363).

Examples of the compound represented by formula (2) include compounds having structures shown in 2-1 to 2-48 below, but the present invention is not limited thereto. Note that in formulas (2-1) to (2-48), M ¹ has the same definition as in formula (2).

The group represented by M ¹ is not particularly limited, and examples thereof include ZnY ¹ , MgY ² , Sn(Y ³ ) ₃ , B(OY ⁴ ) ₂ and the like. Among these, B(OY ⁴ ) ₂ is preferred.

Although ZnY ¹ and MgY ² are not particularly limited, examples thereof include ZnCl, ZnBr, ZnI, MgCl, MgBr, MgI, and the like.
Sn(Y ³ ) ₃ is not particularly limited, but examples include Sn(Me) ₃ and Sn(Bu) ₃ .
Examples of B(OY ⁴ ) ₂ include, but are not limited to, B(OH) ₂ , B(OMe) ₂ , B(O ⁱ Pr) ₂ , B(OBu) ₂ , B(OPh) _2nd grade can be exemplified. Note that Me represents a methyl group, ⁱ Pr represents an isopropyl group, Bu represents a butyl group, and Ph represents a phenyl group.

In addition, examples of B(OY ⁴ ) ₂ in which two (OY ⁴ ) groups come together to form a ring with a boron atom are not particularly limited, but include the following ( The groups represented by I) to (VI) can be exemplified, and the group represented by (II) is preferred in terms of good yield.

Compound (3) used in Step 1 can be produced, for example, according to JP-A-2013-93432. Alternatively, commercially available products may be used.
Examples of compound (3) include the following 3-1 to 3-60, but the present disclosure is not limited thereto. Note that in formulas (3-1) to (3-60), X ¹ has the same definition as in formula (3).

The leaving group represented by X ¹ is a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group, or an iodine atom. A chlorine atom or a bromine atom is preferred in terms of a good yield of the triazine compound (1a). However, it may be preferable to use a trifluoromethanesulfonyloxy group due to the 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-allylpalladium chloride dimer, palladium acetylacetonate, 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-tert-butylphosphine)palladium, bis(tricyclohexylphosphine) palladium, a palladium complex having a tertiary phosphine such as 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 tertiary phosphine that can be used in this case 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-xylyl)phosphine, (±)-2,2'-bis(diphenylphosphino) )-1,1'-binaphthyl, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and the like.

Among these, palladium complexes having tertiary phosphine as a ligand are preferable from the viewpoint of high yield, and palladium complexes having tertiary phosphine as a ligand are preferable because they have a high yield. More preferred are palladium complexes having it as a child.

The molar ratio of tertiary phosphine and 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. There is no limit to the amount of palladium catalyst used in Step 1, but from the viewpoint of a good yield, the molar equivalent of the palladium catalyst is preferably in the range of 0.005 to 0.5 molar equivalent relative to the boron compound.

The base used in step 1 is not particularly limited, but includes, 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 ethoxide, potassium isopropyl oxide, and potassium tert-butoxide; and the like. Among them, metal carbonates and metal phosphates are preferred, and potassium carbonate or potassium phosphate is more preferred, from the standpoint of good reaction yield. There is no particular restriction on the amount of the base, but in terms of good reaction yield, 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. More preferably, it is within the range of .

Step 1 can be carried out in a solvent, such as water; diisopropyl ether, dibutyl ether, cyclopentyl methyl ether (CPME), tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,4-dioxane, dimethoxyethane. ethers such as benzene, toluene, xylene, mesitylene, tetralin, etc.; carbonic acid 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 sulfoxides such as dimethyl sulfoxide (DMSO); and methanol, ethanol, isopropyl alcohol, butanol. , octanol, benzyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 2,2,2-trifluoroethanol, and other alcohols; Good too. There is no particular restriction on the amount of solvent used. Among these, water, ether, amide, alcohol, or a mixed solvent thereof is preferred in terms of a good reaction yield, and a mixed solvent of THF and water is more preferred.

Step 1 can be carried out at a temperature suitably selected from 0°C to 200°C, and is preferably carried out at a temperature suitably selected from 40°C to 150°C in view of a good reaction yield.
Step 1 can be obtained by carrying out usual treatment after the completion of the reaction. If necessary, it may be purified by recrystallization, column chromatography, sublimation, preparative HPLC, or the like.

Next, Step 2 will be explained.
Step 2 is a step in which the compound represented by formula (4) and the compound represented by formula (5) are subjected to a coupling reaction to produce triazine compound (1b). Here, the coupling reaction is preferably performed in the presence of a catalyst. 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, Migita-Kosugi-Stille reaction, etc. I can do it. When applying the reaction conditions of the Suzuki-Miyaura reaction 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 formula (4) used in step 2 can be produced, for example, according to the method disclosed in JP-A-2018-115151.
The triazine compound represented by formula (4) is a compound in which M ¹ in formulas (2-1) to (2-36), which are specific examples of the compound represented by formula (2), is replaced with X ² . I can give an example. Here, X ² has the same definition as in formula (4).

The leaving ^group represented by A chlorine atom or a bromine atom is preferable because of its good properties.

The compound represented by formula (5) used in step 2 can be produced, for example, according to Dyes and Pigments, vol. 134, p. 266, 2016. In addition, it can be synthesized from the compound represented by formula (3) using a general reaction for synthesizing organometallic compounds (for example, Angew.Chem.Int.Ed.2007, 46, 5359-5363), Commercially available products may also be used.

The compound represented by formula (5) can be exemplified by a skeleton in which X ¹ in the compounds represented by formulas (3-1) to (3-60) is replaced with M ² . M ² has the same definition as in 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 preferable configuration is also the same. be.

Further, the triazine compound (1c) contained in the triazine compound (1) can be produced according to the method shown in Step 3 below.

In the formula, Ar ¹ , Ar ² , Ar ³ , R and Z have the same meanings as above;
^X3 represents a chlorine atom, a bromine atom, a trifluoromethanesulfonyloxy group, or an iodine atom;
M ³ represents ZnY ¹ , MgY ² , Sn(Y ³ ) ₃ or B(OY ⁴ ) ₂ ;
Y ³ are the same or different and represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group. Further, two (OY ⁴ ) groups may be combined to form a ring together with the bonded boron atom.

Next, step 3 will be explained.
Step 3 is a step of producing a triazine compound (1c) by coupling a compound represented by formula (6) and a compound represented by formula (7), for example, in Synthesis Example- By applying the conditions shown in 6, it can be obtained in good yield. Here, the coupling reaction is preferably performed in the presence of a catalyst. As the catalyst, a palladium catalyst is preferred.

The triazine compound represented by formula (6) used in Step 3 can be produced, for example, according to the method disclosed in Dyes and Pigments, Volume 157, Page 377, 2018.

The leaving ^group represented by A chlorine atom is preferable because of its good properties.

The compound represented by formula (7) used in step 3 can be obtained in good yield by applying, for example, the conditions shown in Synthesis Example-6 described below. In addition, it can be synthesized from the compound represented by formula (3) using a general reaction for synthesizing organometallic compounds (for example, Angew.Chem.Int.Ed.2007, 46, 5359-5363), Commercially available products may also be used.

As the palladium catalyst, base, solvent, reaction temperature, and post-treatment (purification) that can be used in Step 3, the same ones as those exemplified in Step 1 can be exemplified, and the preferable configuration is also the same. be.
Preferred examples of the triazine compound (1c) obtained in Step 3 include compounds having structures from 1-28 to 1-39.

The triazine compound (1) can be used, for example, in organic electronic devices 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.

<Materials for organic electroluminescent devices>
An organic electroluminescent device material according to one embodiment of the present disclosure contains the above-described triazine compound (1).
The triazine compound (1) can be used, for example, as an electron transport material for organic electroluminescent devices. The organic electroluminescent device material containing the triazine compound (1) achieves high levels of driving voltage, luminous efficiency, and lifetime, and contributes to the production of organic electroluminescent devices that can be used for various purposes and in various environments. It is.

<Organic electroluminescent device>
An organic electroluminescent device material according to one embodiment of the present disclosure contains the above-described triazine compound (1).

<Organic electroluminescent device>
An organic electroluminescent device (hereinafter sometimes simply referred to as an organic electroluminescent device) containing the triazine compound (1) will be described below.
An organic electroluminescent device according to one embodiment of the present disclosure contains a triazine compound (1).
The structure of the organic electroluminescent device is not particularly limited, but examples include the following structures (i) to (v).
(i): Anode/Emissive layer/Cathode (ii): Anode/Hole transport layer/Emissive layer/Cathode (iii): Anode/Emissive 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 in terms of superior luminescent properties of the organic electroluminescent device, it is preferred from the group consisting of the light-emitting layer and the layer between the light-emitting layer and the cathode. It is preferably included in one or more selected layers. Therefore, in the case of the configurations 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 transport layer, and an electron injection layer. .

Hereinafter, an organic electroluminescent device according to one embodiment of the present disclosure will be described in more detail with reference to FIG. 1, taking the configuration (v) above as an example.
Note that although the organic electroluminescent device shown in FIG. 1 has a so-called bottom emission type device configuration, the organic electroluminescent device according to one embodiment of the present disclosure is not limited to the bottom emission type device configuration. do not have. That is, the organic electroluminescent device according to one embodiment of the present disclosure may have other known device configurations such as a top emission type.

FIG. 1 is a schematic cross-sectional view showing an example of a stacked structure of an organic electroluminescent element containing a triazine compound according to one embodiment 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 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 transport layer 6, or the hole injection layer 3 may be omitted and the hole transport layer 4 may be provided directly on the anode 2. Good too. In addition, a single layer that has the functions of multiple layers, such as an electron injection/transport layer that has both the functions of an electron injection layer and an electron transport layer in a single layer, may be used as a layer. A configuration may be provided instead of. Furthermore, 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). Note that the triazine compound (1) may be included in a plurality of layers included in the organic electroluminescent device.
In addition, below, the organic electroluminescent element 100 in which the electron transport layer 6 contains a triazine compound (1) is demonstrated.

[Substrate 1]
The substrate 1 is not particularly limited, and examples thereof include a glass plate, a quartz plate, a plastic plate, and the like.
Examples of the substrate 1 include a glass plate, a quartz plate, a plastic plate, and a plastic film. Among these, glass plates, quartz plates, and light-transmitting plastic films are preferred.
Examples of light-transmitting plastic films include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, and polycarbonate (PC). ), cellulose triacetate (TAC), cellulose acetate propionate (CAP), and the like.
Note that in the case of a configuration in which light emission is extracted from the substrate 1 side, the substrate 1 is transparent 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 material for the anode include metals with a large work function (for example, 4 eV or more), alloys, electrically conductive compounds, and mixtures thereof. Specific examples of the material 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 in which the emitted light is extracted through an anode, the anode is formed of an electrically conductive transparent material that is transparent or substantially transparent to the emitted light.

[Hole injection layer 3, hole transport layer 4]
Between the anode 2 and a light emitting layer 5, which will be described later, a hole injection layer 3 and a hole transport layer 4 are provided in this order 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. As a result, many holes are injected into the light emitting layer at a lower electric field.

Further, the hole injection layer and the hole transport layer also function as electron barrier layers. That is, electrons injected from the cathode and transported from the electron injection layer and/or the electron transport layer to the light emitting layer are blocked 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 to the hole injection layer and/or hole transport layer is suppressed. As a result, the electrons are accumulated at the interface within the light-emitting layer, resulting in effects such as improved light-emitting efficiency, and an organic electroluminescent device with excellent light-emitting performance can be obtained.

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

Specific examples of materials for the hole injection layer and hole transport layer include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, and amino-substituted chalcone. Derivatives, oxazole derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers (especially 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 preferred, and aromatic tertiary amine compounds are particularly preferred, since they provide good performance for organic electroluminescent devices.

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] Examples 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 cited as examples of materials for the hole injection layer and hole transport layer.

The hole injection layer and the hole transport layer may have a single structure made of one or more materials, or may have a laminated structure made of multiple 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 an electron transport layer 6, which will be described later.
Examples of materials for the light-emitting layer include phosphorescent materials, fluorescent materials, and thermally activated delayed fluorescent materials. In the light-emitting layer, electron-hole pairs recombine, resulting in light emission.

The emissive layer may consist of a single small molecule material or a single polymeric material, but more commonly it consists of a host material doped with a guest compound. Luminescence arises 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-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, etc.].

Examples of fluorescent dopants include anthracene, pyrene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, quinacridone, dicyanomethylenepyran compound, thiopyran compound, polymethine compound, pyrylium, thiapyrylium compound, fluorene derivative, periflanthene derivative, and indenoperylene. Examples include derivatives, bis(azinyl)amine boron compounds, bis(azinyl)methane compounds, carbostyryl compounds, and the like. 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 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)), and FIrPic(bis(3,5- difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium(III)) and the like.

Furthermore, the luminescent material is not limited to being contained only in the luminescent layer. For example, the luminescent material may be contained in a layer adjacent to the luminescent layer (hole transport layer 4 or electron transport layer 6). This further increases 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 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 an electron injection layer 7, which will be described later.
The electron transport layer has a function of transmitting electrons injected from the cathode to the light emitting layer. By interposing the electron transport layer between the cathode and the emissive layer, electrons are injected into the emissive layer at a lower electric field.

As described above, the electron transport layer preferably contains the triazine compound (1). Moreover, in addition to the triazine compound (1), the electron transport layer may further contain one or more types selected from conventionally known electron transport materials.
Note that if the triazine compound (1) is not included in the electron transport layer but is included in another layer, one or more types selected from conventionally known electron transport materials may be used as the electron transport material constituting the electron transport layer. I can do it.

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

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

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

[Electron injection layer 7]
An electron injection layer 7 is provided between the electron transport layer 6 and a cathode 8, which will be described later.
The electron injection layer has a function of transmitting electrons injected from the cathode to the light emitting layer. By interposing the electron injection layer between the cathode and the emissive layer, electrons are injected into the emissive layer at a lower electric field.

Examples of materials for the electron injection layer include fluorenone, anthraquinodimethane, diphenoquinone, thiopyrane dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane, anthrone, etc. Examples include organic compounds. In addition, materials for the electron injection layer include various oxides, nitrides, and oxynitrides such as SiO ₂ , AlO, SiN, SiON, AlON, GeO, LiO, LiON, TiO, TiON, TaO, TaON, TaN, and C. Also included are inorganic compounds such as.

[Cathode 8]
A cathode 8 is provided on the electron injection layer 7.
In the case of an organic electroluminescent device configured such that only light emitted from the anode is extracted, the cathode can be formed from any conductive material.
Examples of the material for the cathode include metals with a small work function (hereinafter also referred to as electron-injecting metals), alloys, electrically conductive compounds, and mixtures thereof. Here, the metal with a small work function is, for example, a metal with 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 ). Mixtures, indium, lithium/aluminum mixtures, rare earth metals, and the like.
Among these, from the viewpoint of electron injection properties and durability against oxidation, mixtures of electron injection metals and second metals that are stable metals with a larger work function value, such as magnesium/silver mixtures, magnesium /aluminum mixture, magnesium/indium mixture, aluminum/aluminum oxide (Al ₂ O ₃ ) mixture, lithium/aluminum mixture, etc. are preferred.

[Formation method of each layer]
Each layer other than the electrodes (anode, cathode) described above is formed by forming a thin film by a known method such as a vacuum evaporation method, a spin coating method, a casting method, or an LB (Langmuir-Blodgett method) method. be able to. The materials for each layer may be used alone, or may be used together with materials such as a binder resin and a solvent, if necessary.
The thickness of each layer formed in this way 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 and the cathode can be formed by forming an electrode material into a thin film 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 cathode is preferably 1 μm or less, more preferably 10 nm or more and 200 nm or less.

Note that the layer containing the triazine compound (1) may be formed in combination with the above-mentioned conventionally known electron-transporting materials. 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).

Organic electroluminescent elements may be used as a type of lamp for illumination or as an exposure light source, or as a type of projection device that projects images onto a screen, or as a type of display that allows direct viewing of still or moving images. It may also be used as a device (display). When using an organic electroluminescent element as a display device for video playback, the driving method may be a simple matrix (passive matrix) method or an active matrix method. Furthermore, by using two or more types of organic electroluminescent elements that emit light of different colors, it is possible to produce a full-color display device.

The triazine compound (1) can provide an organic electroluminescent device with superior luminous efficiency when used as an electron transport layer, compared to conventionally known triazine compounds. Furthermore, the triazine compound (1) is highly amorphous due to its sterically hindered skeleton and has high film quality stability. Therefore, effects such as improved driving stability of the organic electroluminescent device and improved luminous efficiency can be obtained.

By using the triazine compound (1) as an electron transport layer of an organic electroluminescent device, it is possible to achieve both low voltage driving and high efficiency of the device. Furthermore, the organic electroluminescent device using the triazine compound (1) can exhibit low voltage drive and high efficiency.

EXAMPLES Hereinafter, the present invention will be explained in more detail based on Examples, but the present invention should not be interpreted as being limited by these Examples.

[ ¹ H-NMR measurement]
For ¹ H-NMR measurement, Bruker ASCEND 400 (400 MHz; manufactured by BRUKER) was used. 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)]
The glass transition temperature was measured using a DSC (differential scanning calorimetry) device DSC6220 (product name, manufactured by Hitachi High-Tech Science) under a nitrogen atmosphere (flow rate 50 ml/min). Aluminum oxide (Al ₂ O ₃ ) was used as a reference in the DSC measurement, and the measurement was performed using 10 mg of the sample.
As a pretreatment for measurement, the sample was melted by increasing 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 increased from 50° C. at a rate of 10° C./min, and the glass transition temperature, crystallization temperature, and melting point were measured.

[Emission characteristics measurement]
The luminescence characteristics of the organic electroluminescent device were evaluated using a luminance meter BM-9 (product name, manufactured by Topcon Technohouse) by applying a direct current to the device manufactured in each example (described later) in a 25°C environment. did.
In addition, commercially available reagents were used.

Synthesis Example-1

Under argon atmosphere, 2,4-diphenyl-6-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,1':2',1''-terphenyl-3-yl]-1,3,5-triazine (2.74 g, 4.7 mmol), 3-bromo-1-triphenylsilylbenzene (2.18 g, 5.1 mmol), palladium acetate ( 60 mg, 0.29 mmol) and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (252 mg, 0.58 mmol) were suspended in THF (60 mL). A 2M aqueous potassium carbonate solution (8 mL) was added to this suspension, and the mixture was heated under reflux for 24 hours. After cooling, water and methanol were added to the reaction mixture, and the resulting solid was collected by filtration. By washing the obtained solid with toluene, the desired 2,4-diphenyl-6-[3-triphenylsilyl-1,1':5',1'':2'',1'''- Quaterphenyl-3'-yl]-1,3,5-triazine (1-41) was obtained (3.09 g, 3.88 mmol, 83%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 6.84 (tt, J=7.4, 1.2 Hz, 1H), 7.02 (ddd, J=8.0, 7.6, 1. 4Hz, 2H), 7.18 (dd, J = 8.0, 1.0Hz, 2H), 7.38-7.67 (m, 30H), 8.68 (dd, J = 1.6Hz, 1H ), 8.73 (ddd, 6.8, 1.6, 1.6Hz, 4H), 8.76 (dd, J=1.6Hz, 1H)

The obtained 2,4-diphenyl-6-[3-triphenylsilyl-1,1':5',1'':2'',1'''-quaterphenyl-3'-yl]-1 , 3,5-triazine had a glass transition temperature of 110°C.

Synthesis Example-2

Under argon atmosphere, 2,4-diphenyl-6-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-biphenyl-5-yl]-1,3 , 5-triazine (2.69 g, 5.3 mmol), 3-bromo-1-triphenylsilylbenzene (2.40 g, 5.8 mmol), palladium acetate (60 mg, 0.29 mmol), 2-dicyclohexylphosphino- 2',4',6'-triisopropylbiphenyl (252 mg, 0.58 mmol) was suspended in THF (60 mL). A 2M aqueous potassium carbonate solution (8 mL) was added to this suspension, and the mixture was heated under reflux for 24 hours. After cooling, water and methanol were added to the reaction mixture. The precipitated solid is collected by filtration and washed with toluene to obtain the desired 2,4-diphenyl-6-[3-triphenylsilyl-1,1':5',1''-terphenyl-3'- [yl]-1,3,5-triazine (1-40) was obtained (2.66 g, 3.7 mmol, 70%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 7.38-7.47 (m, 9H), 7.51-7.68 (m, 16H), 7.18 (dd, J=8.0 , 1.0Hz, 2H), 7.75 (dd, J=7.1, 1.4Hz, 1H), 7.86 (ddd, 7.7, 1.8, 1.3Hz, 1H), 7. 94 (dd, J=1.8, 1.8Hz, 1H), 8.00 (s, 1H), 8.77 (ddd, J=6.7, 1.5, 1.4Hz, 4H), 8 .90 (dd, 1.6, 1.6Hz, 1H), 8.95 (dd, 1.6, 1.6Hz, 1H).

Synthesis Example-3

Under argon atmosphere, 2,4-diphenyl-6-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,1':2',1''-terphenyl-3-yl]-1,3,5-triazine (3.14 g, 5.3 mmol), 4-bromo-1-triphenylsilylbenzene (2.23 g, 5.9 mmol), palladium acetate ( 60 mg, 0.29 mmol), 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (254 mg, 0.58 mmol) were suspended in THF (60 mL). A 2M aqueous potassium carbonate solution (8 mL) was added to this suspension, and the mixture was heated under reflux for 24 hours. After cooling, water and methanol were added to the reaction mixture. The precipitated solid is collected by filtration and washed with toluene to obtain the desired 2,4-diphenyl-6-[4-triphenylsilyl-1,1':5',1'':2'',1'''-quaterphenyl-3'-yl]-1,3,5-triazine (1-2) was obtained (3.09 g, 3.9 mmol, 84%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 7.13-7.24 (m, 2H), 7.26-7.30 (m, 4H), 7.39 (dd, J = 1.6 , 1.4Hz, 1H), 7.40-7.59 (m, 16H), 7.60-7.64 (m, 10H), 7.65-7.66 (m, 2H), 8.68 (dd, J=1.6, 1.6Hz, 1H), 8.74 (ddd, 6.8, 1.7, 1.4Hz, 4H), 8.85 (dd, J=1.7, 1 .6Hz, 1H).

Synthesis Example-4

Under argon atmosphere, 2,4-diphenyl-6-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-biphenyl-5-yl]-1,3 , 5-triazine (2.76 g, 5.4 mmol), 4-bromo-1-triphenylsilylbenzene (2.37 g, 5.8 mmol), palladium acetate (60 mg, 0.29 mmol), 2-dicyclohexylphosphino- 2',4',6'-triisopropylbiphenyl (252 mg, 0.58 mmol) was suspended in THF (60 mL). A 2.0M aqueous potassium carbonate solution (8 mL) was added to this suspension, and the mixture was heated under reflux for 24 hours. After cooling, water and methanol were added to the reaction mixture. The resulting solid is collected by filtration and washed with toluene to obtain the desired 2,4-diphenyl-6-[4-triphenylsilyl-1,1':5',1''-terphenyl-3'- ]-1,3,5-triazine (1-1) was obtained (2.68 g, 3.8 mmol, 70%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 7.39-7.50 (m, 10H), 7.51-7.67 (m, 14H), 7.75 (dd, J=8.2 , 1.8Hz, 2H), 7.81 (ddd, J=8.3, 8.2, 1.1, 4H), 8.07 (dd, J=1.8, 1.8Hz, 1H), 8.80 (ddd, J=6.4, 2.0, 1.4Hz, 4H), 8.98-9.01 (m, 2H).

Glass transition temperature of the obtained 2,4-diphenyl-6-[4-triphenylsilyl-1,1':5',1''-terphenyl-3'-yl]-1,3,5-triazine The temperature was 119℃.

Synthesis Example-5

Under argon atmosphere, 2,4-diphenyl-6-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,1':2',1''-terphenyl-3-yl]-1,3,5-triazine (5.00 g, 8.5 mmol), 1-trifluoromethylsulfonyloxy-4-triphenylmethylbenzene (4.31 g, 9.3 mmol) ), palladium acetate (96 mg, 0.43 mmol), and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (409 mg, 0.86 mmol) were suspended in THF (80 mL). A 2M aqueous potassium carbonate solution (14 mL) was added to this suspension, and the mixture was heated under reflux for 24 hours. After cooling, water and methanol were added to the reaction mixture. The precipitated solid is collected by filtration and washed with toluene to obtain the desired 2,4-diphenyl-6-[4-triphenylmethyl-1,1':5',1'':2'',1'''-quaterphenyl-3'-yl]-1,3,5-triazine (1-66) was obtained (2.08 g, 3.4 mmol, 40%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 7.15-7.25 (m, 8H), 7.25-7.32 (m, 15H), 7.36 (ddd, J=8.6 , 2.2, 1.2Hz, 2H), 7.48-7.66 (m, 11H), 8.62 (dd, J=1.6, 1.6Hz, 1H), 8.73 (ddd, J=6.5, 1.6, 1.4Hz, 4H), 8.82(dd, J=1.6Hz, 1H).

Synthesis Example-6

3-chloro-5-triphenylsilylbiphenyl (3.61 g, 8.1 mmol), bis(pinacolato)diboron (2.46 g, 9.7 mmol), palladium acetate (54 mg, 0.24 mmol), to 2-dicyclo Xylphosphino-2',4',6'-triisopropylbiphenyl (231 mg, 0.48 mmol) and potassium acetate (2.37 g, 24 mmol) were suspended in THF (81 mL) and heated under reflux for 18 hours. After cooling to room temperature, water and methanol were added to the reaction mixture, and the resulting solid was collected by filtration. After dissolving the obtained solid in chloroform, activated carbon was added and stirred for a while. After stirring, the desired 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-triphenylsilylbiphenyl was obtained by filtration with Celite. Yield: 3.87 g, yield: 89%).
¹ HNMR (CDCl ₃ ) δ1.31 (s, 12H), 7.30 (td, J=7.4, 2.5Hz, 1H), 7.35-7.41 (m, 8H), 7.41 -7.46 (m, 3H), 7.51-7.54 (m, 2H), 7.60 (td, J=6.5, 2.5Hz, 6H), 7.87 (dd, J= 1.1, 0.8Hz, 1H), 8.07 (t, J=1.1Hz, 1H), 8.12 (dd, J=1.1, 0.8Hz, 1H).

Synthesis Example-A

Under argon atmosphere, 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-triphenylsilylbiphenyl (3.00 g, 5.57 mmol), 2- Chloro-4,6-diphenyl-1,3,5-triazine (1.49 g, 5.57 mmol) and tetrakis(triphenylphosphine)palladium (322 mg, 0.28 mmol) were suspended in THF (56 mL). A 2.0M potassium phosphate aqueous solution (8.4 mL) was added to this suspension, and the mixture was heated under reflux for 14 hours. After cooling, water and methanol were added to the reaction mixture. The resulting solid was collected by filtration. The obtained solid was purified by silica gel column chromatography (hexane/chloroform) to obtain the desired 2,4-diphenyl-6-[(5-phenyl-3-triphenylsilyl)phenyl]-1,3,5 -triazine (1-28) was obtained (yield: 3.21 g, yield: 90%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 7.40 (tt, J=7.6, 1.3Hz, 1H), 7.43-7.59 (m, 15H), 7.62 (tt , J=7.6, 0.7Hz, 2H), 7.68-7.73(m, 8H), 8.10(dd, J=1.8, 0.5Hz, 1H), 8.68( dt, J=6.9, 1.5Hz, 4H), 9.01 (dd, J=5.9, 1.8Hz, 1H).

Synthesis Example-7

Under argon atmosphere, 2-[5-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-4,6-diphenyl-1,3, 5-triazine (2.04 g, 4.00 mmol), 3-chloro-1-triphenylgermylbenzene (1.96 g, 4.60 mmol), palladium acetate (45 mg, 0.20 mmol) and 2-dicyclohexylphosphino- 2',4',6'-triisopropylbiphenyl (191 mg, 0.40 mmol) was suspended in THF (40 mL). A 2M aqueous potassium phosphate solution (6.0 mL) was added to this suspension, and the mixture was heated under reflux for 18 hours. After cooling, water and methanol were added to the reaction mixture. The resulting solid was collected by filtration. The obtained solid was purified by silica gel column chromatography (hexane/chloroform) to obtain the desired 2,4-diphenyl-6-[(5-phenyl-3-triphenylgermyl)phenyl]-1,3, 5-triazine (1-74) was obtained (yield 1.81 g, yield 59%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 9.04 (dt, J = 9.0, 1.7 Hz, 2H), 8.81 (dt, J = 6.8, 1.7 Hz, 4H) , 8.24 (td, J=7.0, 1.5Hz, 4H), 8.13 (t, J=1.7Hz, 1H), 8.10 (t, J=1.8Hz, 1H), 8.00 (s, 2H), 7.91 (td, J = 7.7, 1.4Hz, 1H), 7.84 (d, J = 1.2Hz, 1H), 7.82 (t, J = 1.3Hz, 1H), 7.72 (t, J = 7.7Hz, 1H), 7.50-7.63 (m, 15H), 7.42-7.49 (m, 4H).

Synthesis Example-8

Under argon atmosphere, 2,4-diphenyl-6-[3-chloro-4-(4-pyridyl)phenyl]-1,3,5-triazine (147 mg, 0.35 mmol), 4,4,5,5- Tetramethyl-2-[3-(trimethylsilyl)phenyl]-1,3,2-dioxaborolane (125 mg, 0.45 mmol), palladium acetate (2.4 mg, 0.01 mmol), 2-dicyclohexylphosphino-2', 4',6'-triisopropylbiphenyl (10 mg, 21 μmol) was dissolved in tetrahydrofuran (3.5 mL). A 2M aqueous potassium carbonate solution (0.5 mL) was added thereto, and the mixture was stirred at 80°C for 24 hours. After cooling to room temperature, low-boiling components were distilled off under reduced pressure, chloroform and water were added to the obtained solid, and the organic layer was extracted. The organic layer was dried over sodium sulfate, and low-boiling components were distilled off under reduced pressure. The obtained crude product was purified by column chromatography to obtain 2,4-diphenyl-6-[2-(4-pyridyl)-3'-trimethylsilylbiphenyl-5-yl]-1,3,5-triazine. A white solid (1-94) was obtained (yield: 182 mg, yield: 98%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 0.14 (s, 9H), 7.12-7.14 (m, 2H), 7.24 (s, 1H), 7.38-7. 48 (m, 3H), 7.56-7.65 (m, 7H), 8.49-8.51 (m, 2H), 8.78-8.81 (m, 4H), 8.85 ( dd, J=8.0, 1.8Hz, 1H), 8.90 (d, J=1.6Hz, 1H)

Synthesis Example-9

Under argon atmosphere, 2-[4-chloro-2-(9-phenanthrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine (104 mg, 0.20 mmol), 4,4,5,5- Tetramethyl-2-[3-(triphenylsilyl)phenyl]-1,3,2-dioxaborolane (120 mg, 0.26 mmol), palladium acetate (1.3 mg, 6 μmol), 2-dicyclohexylphosphino-2', 4',6'-triisopropylbiphenyl (5.7 mg, 12 μmol) was dissolved in tetrahydrofuran (2 mL). A 2M aqueous potassium carbonate solution (0.6 mL) was added thereto, and the mixture was stirred at 80°C for 24 hours. After cooling to room temperature, low-boiling components were distilled off under reduced pressure, and the residue was washed with water and methanol to obtain a crude product. By purifying the obtained crude product by column chromatography, 2,4-diphenyl-6-[2-(9-phenanthrenyl)-3'-triphenylsilyl(biphenyl-4-yl)]-1, A white solid of 3,5-triazine (1-95) was obtained (yield: 122 mg, yield: 74%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 7.18 (t, J = 8.0 Hz, 4H), 7.36-7.51 (m, 13H), 7.55-7.72 (m , 12H), 7.76 (d, J = 1.8Hz, 1H), 7.78-7.82 (m, 2H), 7.87 (d, J = 7.8Hz, 1H), 7.95 -7.99 (m, 5H), 8.70-8.73 (m, 3H)

Synthesis Example-10

Under argon atmosphere, 2-[5-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-4,6-diphenyl-1,3, 5-triazine (1.27 g, 2.5 mmol), 3-bromo-1-diphenylmethylsilylbenzene (1.06 g, 3.0 mmol), palladium acetate (28 mg, 0.13 mmol), 2-dicyclohexylphosphino-2 ',4',6'-triisopropylbiphenyl (119 mg, 0.25 mmol) was suspended in tetrahydrofuran (25 mL). A 2M aqueous potassium carbonate solution (7.5 mL) was added to this suspension, and the mixture was stirred at 80°C for 20 hours. After cooling to room temperature, low-boiling components were distilled off under reduced pressure, and the residue was washed with water and methanol to obtain a crude product. By purifying the obtained crude product by column chromatography, 2,4-diphenyl-6-[3-(diphenylmethylsilyl)-1,1':5',1''-terphenyl-3' -yl]-1,3,5-triazine (1-164) was obtained as a white solid (yield: 1.42 g, yield: 87%).
¹ H-NMR (CDCl ₃ ) δ (ppm): 0.94 (s, 3H), 7.37-7.47 (m, 7H), 7.52-7.66 (m, 14H), 7. 94 (brs, 1H), 7.96 (t, J = 1.7Hz, 1H), 8.79 (dt, J = 6.8, 1.7Hz, 4H), 8.93 (t, J = 1 .7Hz, 1H), 8.95 (t, J=1.7Hz, 1H).

Synthesis Example-11

Under argon atmosphere, 4,6-diphenyl-2-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-biphenyl-5'-yl]-1, 3,5-triazine (2.76g, 5.42mmol), 3-bromo-1-triphenylsilylbenzene (2.37g, 5.76mmol), palladium acetate (60mg, 0.29mmol), 2-dicyclohexylphosphino -2',4',6'-triisopropylbiphenyl (252 mg, 0.58 mmol) was suspended in THF (60 mL). A 2M aqueous potassium carbonate solution (8 mL) was added to this suspension, and the mixture was heated under reflux for 24 hours. After cooling, water and methanol were added to the reaction mixture. The resulting solid was collected by filtration and recrystallized with toluene to obtain 4,6-diphenyl-2-[3-triphenylsilyl-(1,1':3',1'')-terphenyl-3''-yl]-1,3,5-triazine (1-171) was obtained as a white solid (2.68 g, 70%).
¹ H-NMR (CDCl ₃ ) δ7.39-7.50 (m, 10H), 7.51-7.67 (m, 14H), 7.75 (dd, J=8.2, 1.8Hz, 2H), 7.81 (ddd, J = 8.3, 8.2, 1.1Hz, 4H), 8.07 (dd, J = 1.8, 1.8Hz, 1H), 8.80 (ddd , J=6.4, 2.0, 1.4Hz, 4H), 8.98-9.01 (m, 2H).

Reference example-1

Under a nitrogen atmosphere, 2-[3-chloro-5-(phenanthren-9-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (1.00 g, 1.9 mmol), phenylboronic acid ( 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 aqueous tripotassium phosphate solution (2.9 mL, 5.8 mmol) were added to a 300 mL four-necked flask and stirred at 95° C. for 6 hours. After the resulting reaction solution was allowed to cool to room temperature, water (100 mL) was added to the reaction mixture, and 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 to obtain the target product, 2,4-diphenyl-6-[5-(phenanthren-9-yl)-biphenyl-3-yl]-1,3, A gray powder (700 mg, yield 65%) of 5-triazine (compound ETL-1) was obtained.

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.

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).

Next, device evaluation was performed using the obtained compound.

Element example-1 (see Figure 2)

(Preparation of substrate 1 and anode 2)
A glass substrate with an ITO transparent electrode on which a 2 mm wide indium-tin oxide (ITO) film (film thickness: 110 nm) was patterned in stripes was prepared as a substrate 1 having an anode 2 on its surface. Next, this substrate was cleaned with isopropyl alcohol, and then surface-treated by ozone ultraviolet cleaning.

(Preparation for vacuum deposition)
Each layer was vacuum-deposited using a vacuum evaporation method on the surface-treated substrate after cleaning, and each layer was laminated.
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 manufactured according to the film forming conditions in the following order. Note that 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 A 10 nm film was formed of -2-amine and 1,2,3-tris[(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane at a ratio of 99:1 (mass ratio). , a hole injection layer 3 was produced. The film 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 to a thickness of 85 nm at a rate of 0.2 nm/sec to produce the first hole transport layer 41.

(Preparation of second hole transport layer 42)
A 5 nm film of N-phenyl-N-(9,9-diphenylfluoren-2-yl)-N-(1,1'-biphenyl-4-yl)amine purified by sublimation was formed at a speed of 0.15 nm/sec. , the 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 A 20 nm thick film was formed at a ratio of 95:5 (mass ratio) to produce a light-emitting layer 5. The film deposition rate was 0.1 nm/sec.

(Preparation of hole blocking layer 6)
2,4-diphenyl-6-[3-triphenylsilyl-1,1':5',1'':2'',1'''-quaterphenyl-3' synthesized in Synthesis Example-1 -yl]-1,3,5-triazine (1-41) was deposited to a thickness of 6 nm at a rate of 0.05 nm/sec to form a hole blocking layer 9.

(Preparation of electron transport layer 7)
Sublimation purified 4,6-diphenyl-2-(4-{4-[4'-cyano-(1,1'-biphenyl)-4-yl]naphthalen-1-yl}phenyl)-1,3,5 - Triazine and 8-hydroxyquinolinolate lithium (hereinafter referred to as Liq) were formed into a 25 nm film at a ratio of 50:50 (mass ratio) to form an electron transport layer 6. The film deposition rate was 0.15 nm/sec.

(Preparation of electron injection layer 8)
Liq was deposited to a thickness of 1 nm at a rate of 0.02 nm/sec to produce an electron injection layer 7.

(Preparation of cathode 9)
Finally, a metal mask was placed so as to be perpendicular to the ITO stripe (anode 2) on the substrate 1, and the cathode 8 was formed. The cathode had a two-layer structure by forming films of silver/magnesium (mass ratio 1/10) and silver to have a thickness of 80 nm and 20 nm, respectively, in this order. The deposition rate of silver/magnesium was 0.5 nm/sec, and the deposition rate of silver was 0.2 nm/sec.

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

Element example-2
In Device Example 1, instead of forming a 6 nm film of Compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl- synthesized in Synthesis Example 2 was used. 6-[3-triphenylsilyl-1,1':5',1''-terphenyl-3'-yl]-1,3,5-triazine (1-40) was deposited to a thickness of 6 nm (deposition rate An organic electroluminescent device was fabricated in the same manner as Device Example 1, except that the rate was 0.05 nm/sec).

Element example-3
In Device Example-1, instead of forming a 6 nm film of Compound 1-41 (film-forming rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl- synthesized in Synthesis Example-3 was used. 6-[4-triphenylsilyl-1,1':5',1'':2'',1'''-quaterphenyl-3'-yl]-1,3,5-triazine(1- An organic electroluminescent device was produced in the same manner as in device example 1, except that 2) was deposited to a thickness of 6 nm (film deposition rate: 0.05 nm/sec).

Element example-4
In Device Example 1, instead of forming a 6 nm film of Compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl- synthesized in Synthesis Example 4 was used. 6-[4-triphenylsilyl-1,1':5',1''-terphenyl-3'-yl]-1,3,5-triazine (1-1) was deposited to a thickness of 6 nm (deposition rate An organic electroluminescent device was fabricated in the same manner as Device Example 1, except that the rate was 0.05 nm/sec).

Element example-5
In Device Example 1, instead of forming a 6 nm film of Compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl- synthesized in Synthesis Example 5 was used. 6-[4-triphenylmethyl-1,1':5',1'':2'',1'''-quaterphenyl-3'-yl]-1,3,5-triazine(1- An organic electroluminescent device was produced in the same manner as in Device Example-1, except that 66) was deposited to a thickness of 6 nm (deposition rate: 0.05 nm/sec).

Element example-6
In Device Example 1, instead of forming a 6 nm film of Compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl- synthesized in Synthesis Example 6 was used. Device Example except that 6-[(5-phenyl-3-triphenylsilyl)phenyl]-1,3,5-triazine (1-28) was deposited to a thickness of 6 nm (film deposition rate 0.05 nm/sec) An organic electroluminescent device was produced using the same method as in Example 1.

Element example-7
In Device Example 1, instead of forming a 6 nm film of Compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl- synthesized in Synthesis Example 7 was used. The device was carried out except that 6-[(5-phenyl-3-triphenylgermyl)phenyl]-1,3,5-triazine (1-74) was deposited to a thickness of 6 nm (film deposition rate 0.05 nm/sec). An organic electroluminescent device was produced using the same method as in Example-1.

Element example-8
In Device Example 1, instead of forming a 6 nm film of Compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 4,6-diphenyl- synthesized in Synthesis Example 8 was used. 2-[3-triphenylsilyl-(1,1':3',1'')-terphenyl-3''-yl]-1,3,5-triazine (1-171) was deposited to a thickness of 6 nm ( An organic electroluminescent device was produced in the same manner as in device example 1, except that the film formation rate was 0.05 nm/sec).

Element reference example-1
In device example 1, instead of forming a 6 nm film of compound 1-41 (film formation rate 0.05 nm/sec) on the hole blocking layer 6, 2,4-diphenyl-6 synthesized in reference example 1 was used. -[5-(phenanthrene-9-yl)-biphenyl-3-yl]-1,3,5-triazine (compound ETL-1) was deposited to a thickness of 6 nm (film deposition rate 0.05 nm/sec). An organic electroluminescent device was produced in the same manner as in Device Example-1.

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

As for the luminescence characteristics, the voltage (V) and current efficiency (cd/A) when a current density of 10 mA/cm ² was applied were measured, and the element life during continuous lighting was measured. The device life was determined by measuring the brightness decay time during continuous lighting when the device was driven at an initial brightness of 1000 cd/m ² and the time required for the brightness (cd/m ² ) to decrease by 3%. Note that the values of voltage (V), current efficiency (cd/A), and lifespan are expressed as relative values when Element Reference Example-1 is taken as 100. The results are shown in Table 1.

From Table 1, it was found that the organic electroluminescent device using triazine compound (1) can achieve higher voltage and luminous efficiency than the reference example.

1 Substrate 2 Anode 3 Hole injection layer 41 First hole transport layer 42 Second hole transport layer 5 Light emitting layer 6 Hole blocking layer 7 Electron transport layer 8 Electron injection layer 9 Cathode 100 Organic electroluminescent element

Claims (20)

Triazine compound represented by formula (1):
During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
Represents a phenyl 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, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R represents a phenyl group ;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p represents 0, 1 or 2. The triazine compound according to claim 1, represented by formula (1a), (1b), (1c), (1d), or (1e):
In the formula, Ar ¹ , Ar ² , Ar ³ , R, Z, L and p have the same definitions as in formula (1) above. The triazine compound according to claim 1, represented by formula (1a), formula (1b), or (1c):
In the formula, Ar ¹ , Ar ² , Ar ³ , R, Z, L and p have the same definitions as in formula (1) above. The triazine compound according to claim 1, represented by formula (11a), formula (11b), or formula (11c):
In the formula, Ar ¹ , Ar ² , Ar ³ , R, Z, and L have the same definitions as in the above formula (1);
q represents 0 or 1. The triazine compound according to any one of claims 1 to 4, wherein Z is a carbon atom, a silicon atom, or a germanium atom. The triazine compound according to any one of claims 1 to 5, wherein Z is a silicon atom or a germanium atom. The triazine compound according to any one of claims 1 to 6, wherein Z is a silicon atom. The triazine compound according to any one of claims 1 to 7 , wherein Ar ¹ and Ar ² are each independently a phenyl group or a biphenylyl group. The triazine compound according to any one of claims 1 to 8 , wherein Ar ¹ and Ar ² are the same group. The triazine compound according to any one of claims 1 to 9 , wherein L is a metaphenylene group or a paraphenylene group. The triazine compound according to any one of claims 1 to 10 , wherein L is a metaphenylene group. The triazine compound according to any one of claims 1 to 11 , wherein p is 0 or 1. A method for producing a triazine compound represented by formula (1a), comprising coupling a compound represented by formula (2) and a compound represented by formula (3):
During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
Represents a phenyl 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, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R represents a phenyl group ;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p' represents 1 or 2;
M ¹ represents ZnY ¹ , MgY ² , Sn(Y ³ ) ₃ or B(OY ⁴ ) ₂ ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ are the same or different and represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group;
The two (OY ⁴ ) groups may be combined to form a ring with the boron atom to which the two (OY ⁴ ) groups are bonded;
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 formula (1b), which comprises coupling a compound represented by formula (4) and a compound represented by formula (5):
During the ceremony,
Ar ¹ and Ar ² each independently represent a phenyl group, a biphenylyl group or a naphthyl group;
Ar ³ is
Represents a phenyl 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, an alkyl group having 1 to 4 carbon atoms, and a phenyl group;
R represents a phenyl group ;
L represents a phenylene group;
Z represents a carbon atom, a silicon atom, a germanium atom, or a tin atom;
p'' represents 1 or 2;
^X2 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 ;
Y ¹ and Y ² each independently represent a chlorine atom, a bromine atom or an iodine atom;
Y ³ are the same or different and represent an alkyl group or a phenyl group having 1 to 4 carbon atoms;
Y ⁴ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group;
The two (OY ⁴ ) groups may be combined to form a ring together with the boron atom to which the two (OY ⁴ ) groups are bonded. The method for producing a triazine compound according to claim 13 or 14, wherein M ¹ or M ² is B(OY ⁴ ) ₂ . The method for producing a triazine compound according to any one of claims 13 to 15, wherein Z is a silicon atom or a germanium atom. The method for producing a triazine compound according to any one of claims 13 to 16, wherein Z is a silicon atom. The manufacturing method according to any one of claims 13 to 17 , wherein the coupling reaction is performed in the presence of a palladium catalyst having a tertiary phosphine as a ligand. Any one of claims 13 to 18 , wherein the coupling reaction is carried out in the presence of a palladium catalyst having triphenylphosphine or 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl as a ligand. The manufacturing method according to item 1. An organic electroluminescent device containing the triazine compound according to any one of claims 1 to 12 .

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