JPS6237624B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel 3,6-distyrylcarbazole and its derivatives and methods for producing them. Poly-N- as an organic photoconductive material for electrophotography
Vinyl carbazole is the best known. This compound is usually used by adding a sensitizer, a plasticizer, etc., and coating it thinly on a substrate such as metal or paper. Although this organic photoconductive material has various advantages compared to those using inorganic photoconductive materials such as selenium, it also has disadvantages, with low sensitivity being one of the biggest disadvantages. . Therefore, the present inventors conducted research and examination on various compounds having a carbazole group in order to solve the problems of poly-N-vinylcarbazole and to find a compound that has excellent properties as an organic photoconductive material. As a result, we have discovered 3,6-distyrylcarbazole and its derivatives, which are new compounds useful as intermediates in the synthesis of photoconductive materials. In this compound, a vinyl group or the like can be easily introduced into the N-position, and a photoconductive substance can be produced by polymerizing this compound. The 3,6-distyrylcarbazole derivative of the present invention is a compound having the following general formula []. [However, R is the same or different hydrogen, chlorine, or alkoxy group having 1 or 2 carbon atoms] This 3,6-distyrylcarbazole derivative is represented by the general formula [] [However, X is the same or different bromine or bromine] 3,6-dihalocarbazole and general formula [] [However, R is the same or different hydrogen, chlorine, or alkoxy group having 1 or 2 carbon atoms.] It is produced by reacting with a styrene derivative represented by the following formula. This reaction usually requires a catalyst and a hydrogen halide scavenger. As the catalyst, a combination of a noble metal compound such as palladium acetate and a phosphorus compound such as triarylphosphine is suitable. Suitable hydrogen halide scavengers include amines such as tertiary amines and weakly basic salts such as NaHCO ₃ and Na ₂ CO ₃ . Dihalocarbazole, which is a raw material compound of the present invention, can be produced by halogenating carbazole with bromine or iodine. The dihalocarbazole represented by the general formula [] thus obtained and the styrene derivative represented by the general formula [] are heated at a temperature of 75 to 150°C in the presence of, for example, palladium acetate, triarylphosphine, and a tertiary amine. Make it react. Triarylphosphines include triphenylphosphine, tri-o-tolylphosphine, tris(2,5-diisopropyl)phosphine, tri-α-naphthylphosphine, tris(2,3,
4,5-tetramethylphenyl)phosphine, tris(5-trifluoromethyl-2-methylphenyl)phosphine, tris(2-methyl-5-t
-butylphenyl)phosphine, tris(p-carbomethoxyphenyl)phosphine, etc., but in particular tri-o
-Tolylphosphine, tris(2-methyl-5-
Preference is given to using t-butylphenyl)phosphine. The triarylphosphine used in the present invention is 2 to 10 mol% based on 1 mol of palladium acetate.
is appropriate. Further, the appropriate amount of palladium acetate to be used is 1 to 2 mol% of the amount of styrene derivative used. The tertiary amine is used as a scavenger for the generated hydrogen halide, and may be any common amine such as triethylamine, tri-n-propylamine, tri-n-butylamine, triamylamine, tetramethylethylenediamine, etc. The amount used is slightly in excess of the equivalent mole of hydrogen halide generated. Common reaction solvents may be used, such as N,N-dimethylformamide, dimethylacetamide, toluene, xylene, chlorobenzene, O-dichlorobenzene, N-methylpyrrolidone, dimethylsulfoxide, acetonitrile, and the like. The styrene derivative [] to be reacted with the dihalocarbazole [] may be a combination of two or more kinds, and in that case, the two R's of the 3,6-distyrylcarbazole derivative may be different. However, usually R are the same group. In this case, preferable R is hydrogen, halogen, alkoxy group, nitro group,
and dimethylamino group. The compound obtained by the method of the present invention is useful as an intermediate for photoconductive substance synthesis,
An excellent photoconductor can be obtained by homopolymerizing a compound having a polymerizable functional group introduced into the N-position, which is active as a reaction site, or copolymerizing it with other suitable monomers. Also, excellent photoconductors can be obtained by grafting onto existing polymers with nitrogen atoms. The material obtained in this way has superior photoconductivity compared to poly-N-vinylcarbazole, which is a typical organic photoconductive material, and has high purity, which is essential for photoconductive materials. It will be done. This photoconductive substance is suitable as a photosensitive material for electrophotography like the conventional poly-N-vinylcarbazole, and is mainly used for this purpose, but is of course not limited to that purpose. EXAMPLES The present invention will be specifically explained below using Examples, but the present invention is not limited to these Examples. Example 1 33.44 parts (parts by weight, same hereinafter) of carbazole are added to 500 parts of carbon disulfide and dissolved by heating until carbon disulfide refluxes. While stirring, 72 parts of bromine dissolved in 40 parts of carbon disulfide were added dropwise. After aging under reflux for 1 hour, it is cooled. After washing the precipitate with carbon disulfide, it was thoroughly washed with water. Purified by recrystallization from ethyl alcohol, melting point 213
39.06 parts of 3,6-dipromocarbazole (hereinafter abbreviated as DBC _Z ) was obtained as white needle-like crystals at a temperature of 39.06 parts.
All of the following examples were manufactured using this method.
DBC _Z was used. A mixture consisting of 8.13 parts of DBC _Z , 6.51 parts of styrene, 11.67 parts of tri-n-butylamine, 0.112 parts of palladium acetate, 0.304 parts of tri-o-tolylphosphine, and 20 parts of dimethylformamide was heated at 130°C with stirring under a nitrogen atmosphere. Heated for 20 hours. After filtering the reaction mixture while it is still hot to remove insoluble matter,
Crude crystals were obtained by pouring into a large amount of methanol. The obtained crude crystals were recrystallized twice from chlorobenzene to obtain 5.60 parts of 3,6-distyrylcarbazole (yield 59%) as pale, different-colored plate-like crystals. Melting point: 246℃ (decomposition) Elemental analysis (as C ₂₈ H ₂₁ N) C H N Calculated value (%) 90.53 5.70 3.77 Actual value (%) 90.10 5.99 3.88 Also, its infrared spectrum (KBr method) is shown in Figure 1
Shown below. Examples 2-3 Example-1 except that the indicated styrene derivatives were used
Various distyrylcarbazole derivatives were obtained according to the method of . 【table】

[Brief explanation of the drawing]

Figures 1, 2 and 3 show the 3,6-
FIG. 2 is an IR diagram of a distyrylcarbazole derivative.

Claims (1)

[Claims] 1. General formula [However, R is the same or different hydrogen, chlorine,
a C1 or C2 alkoxy group] A 3,6-distyrylcarbazole derivative represented by the following. 2 formulas [However, X is the same or different bromine or iodine] 3,6-dihalocarbazole represented by the formula [However, R is hydrogen, chlorine, carbon number 1 or 2
one type of alkoxy group of ] A general formula characterized by reacting a styrene derivative represented by [However, the above-mentioned groups are the same or different] A method for producing a 3,6-distyrylcarbazole derivative represented by the following. 3. The method according to claim 2, wherein the hydrogen halide scavenger is a tertiary amine.