JPH08291115A - New triphenylamine compound - Google Patents

Abstract

PURPOSE: To obtain a new triphenylamine compound capable of keeping the amorphous state at normal temperature and forming a thin film as it is, having excellent heat resistance and useful as a photoelectric transducer element, etc., for various electronic devices. CONSTITUTION: This triphenylamine compound is 4,4',4"-tris[N,N-(1-naphthyl) phenylamino]triphenylamine of formula I or 4,4',4"-tris[N,N-(2-naphthyl) phenylamino]triphenylamine of formula II. The compound of formula I can be produced by reacting 4,4',4"-triiodotriphenylamine with a 1- naphthylphenylamine compound and the compound of formula II can be produced by reacting 4,4',4"-triiodotriphenylamine with a 2-naphthylphenylamine compound. The above reactions are carried out in the presence of a base (preferably an alkali metal hydroxide) and copper powder in a solvent (preferably decalin). The compound of formula I has a melting point of 219 deg.C, a molecular weight[M (m/e) by mass spectrometry] of 896 and a glass transition point of 113 deg.C.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel triphenylamine compound useful as an amorphous electronic material,
In detail, since it can maintain the amorphous state at room temperature, it can be thinned by itself, and
Since it has excellent heat resistance, it can be used in various electronic devices.
4,4 ', 4 "-Tris [N, N- (1- or 2-naphthyl), a novel and useful compound that can be practically used as a photoelectric conversion device, thermochromic material for optical memory, etc.
Phenylamino] triphenylamine.

[0002]

2. Description of the Related Art Conventionally, a low molecular weight organic compound having a so-called photo-electronic function which causes conductivity and charge generation by irradiating light has not been capable of forming a thin film by itself, so that a thin film is formed. In order to do so, disperse it in a binder resin (thus, in a diluted state) and apply it on the substrate,
It is necessary to make it thin. Further, even if a relatively stable film can be formed at room temperature, the glass transition temperature is low, so that the heat resistance is poor and it is difficult to use it for a practical device.

[0003]

The present invention, unlike the conventional low molecular weight organic compound having an optical / electronic function,
It can maintain an amorphous state at room temperature, that is, a glass state. Therefore, it can be formed into a thin film by itself without using a binder resin, and has a high glass transition temperature and excellent heat resistance. An object of the present invention is to provide a novel low molecular weight organic compound having a photo / electronic function, which is useful as a practical amorphous electronic material.

[0004]

According to the present invention,

[0005]

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4,4 ', 4 "-tris [N, N-
(1-naphthyl) phenylamino] triphenylamine and the following formula

[0007]

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4,4 ', 4 "-tris [N, N-
Provided is (2-naphthyl) phenylamino) triphenylamine.

The compound according to the present invention contains 4,4 ', 4 "-triiodotriphenylamine and 1- or 2-naphthylphenylamines in the presence of a base and copper powder, depending on the desired compound. Can be obtained by reacting with a solvent.

Alkali metal hydroxides such as potassium hydroxide and sodium hydroxide are preferably used as the base, and hydrocarbons such as decalin are preferably used as the solvent, but are not limited thereto. is not.

4,4 ', 4 "-tris [N, N- (1
-Or 2-naphthyl) phenylamino] triphenylamine plays a role of lowering the oxidation potential of the triaminotriphenylamine structure at the center of the molecule, improving charge injection efficiency and charge transport efficiency, and The asymmetric structure of the phenyl group and the naphthyl group improves the ability to form an amorphous film, and due to the rigidity of the naphthyl group, the glass transition temperature is a high temperature of 100 ° C. or higher,
Thus, it has excellent heat resistance.

The fact that the compound according to the present invention is amorphous and in an amorphous state having no anisotropy is proved by, for example, having a glass transition temperature and showing no clear peak in powder X-ray diffraction. It

[0013]

INDUSTRIAL APPLICABILITY According to the present invention, a novel compound 4,
Provided is 4 ', 4 "-tris [N, N- (1- or 2-naphthylphenylamino] triphenylamine. This compound is capable of maintaining a stable amorphous state, that is, a glass state at room temperature. In addition, it has a high glass transition temperature of 100 ° C. or higher.Therefore, by utilizing the amorphous state of the compound according to the present invention, it is possible to easily form a thin film by itself, for example, a casting method or vacuum deposition. Thus, a thin film having a large area can be easily obtained by using the compound etc. Therefore, the compound according to the present invention can be used as an amorphous electronic material such as a photoelectric conversion element, a thermochromic element, an organic photoreceptor, a charge. It can be suitably used as a transport material, an optical memory device, and the like.

[0014]

EXAMPLES Examples of the present invention will be given below.

Example 1 (Synthesis of 4,4 ', 4 "-tris [N, N- (1-naphthyl) phenylamino] triphenylamine) 1-naphthylphenylamine 5.0 g, 4,4', 4 "-Triiodotriphenylamine 2.0 g, potassium hydroxide 3.8 g,
2.0 g of copper powder and 5 ml of decalin were charged in a three-necked flask and reacted at a temperature of 170 ° C. for 8 hours under a nitrogen atmosphere. After this, the reaction mixture obtained was extracted with toluene,
The obtained toluene solution was subjected to silica gel column chromatography to separate the reaction product. The reaction product was recrystallized from toluene to give 4,4 ', 4 "-tris [N, N
0.8 g of-(1-naphthyl) phenylamino] triphenylamine was obtained.

Melting point: 219 ° C. Mass spectrum: M (m / e) 896 Infrared absorption spectrum: shown in FIG.

Differential Scanning Calorimetry (DSC): When the compound according to the invention is recrystallized, this is melted by heating and cooled,
Form amorphous glass at room temperature. When this amorphous glass is heated again, it shows a glass transition point at 113 ° C. Oxidation potential: When the oxidation potential was measured by cyclic voltammetry, the first oxidation potential showed a low value of 0.08 V, and it can be suitably used as a hole transfer agent.

Example 2 (Synthesis of 4,4 ', 4 "-tris [N, N- (2-naphthyl) phenylamino] triphenylamine) 1-naphthylphenylamine 5.0 g, 4,4', 4 "-Triiodotriphenylamine 2.0 g, potassium hydroxide 3.8 g,
2.0 g of copper powder and 5 ml of decalin were charged into a three-necked flask and reacted at a temperature of 175 ° C. for 8 hours under a nitrogen atmosphere. After this, the reaction mixture obtained was extracted with toluene,
The obtained toluene solution was subjected to silica gel column chromatography to separate the reaction product. The reaction product was recrystallized from toluene to give 4,4 ', 4 "-tris [N, N
0.7 g of-(1-naphthyl) phenylamino] triphenylamine was obtained.

Melting point: 224 ° C. Mass spectrum: M (m / e) 896 Infrared absorption spectrum: Shown in FIG.

Differential Scanning Calorimetry (DSC): When the compound according to the invention is recrystallized, this is melted by heating and cooled,
Form amorphous glass at room temperature. When this amorphous glass is heated again, it shows a glass transition point at 110 ° C. Oxidation potential: When the oxidation potential was measured by cyclic voltammetry, the first oxidation potential showed a low value of 0.11 V, and it can be suitably used as a hole transfer agent.

[Brief description of drawings]

FIG. 1 shows 4,4 ′, 4 ″ -tris [N, N-
1 shows an infrared absorption spectrum of (1-naphthyl) phenylamino] triphenylamine.

FIG. 2 shows 4,4 ′, 4 ″ -tris [N, N-
3 shows an infrared absorption spectrum of (2-naphthyl) phenylamino] triphenylamine.

Claims (2)

[Claims] 1. A 4,4 ′, 4 ″ -tris [N, N- (1-naphthyl) phenylamino] triphenylamine. 2. A 4,4 ', 4 "-tris [N, N- (2-naphthyl) phenylamino) triphenylamine.