JP2560248B2 - Carbazole derivative and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel carbazole derivative and a method for producing the same.

[0002]

2. Description of the Related Art Polycyclic aromatic compounds have properties such as rigidity, high electron density, and photoreactivity at the molecular level. By polymerizing them, for example, they have excellent heat resistance and corrosion resistance. Structural materials, functional materials with optical, electrical or magnetic properties can be produced. The condensed polycyclic aromatic polymer compound is particularly important as a group of compounds having excellent heat resistance and moldability. In particular, carbazole is a compound expected industrially as a constituent element of a photoconductive material.

[0003] Carbazole is used as a functional material such as poly-N-vinyl carbazole, but has a problem in heat resistance due to its structure. The development of materials was awaited. Many polymers having an aromatic group in the main chain, such as aramid and polyarylate, have excellent heat resistance. These polymers are usually produced by reacting a dicarboxylic acid moiety and a diamine or dialcohol moiety, which are constituents, but often have low solubility in solvents and poor moldability.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel carbazole derivative useful as a polyester raw material having excellent heat resistance and moldability, and a method for producing the same.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention.

That is, according to the present invention, the general formula

Embedded image (In the formula, Ph represents a phenyl group, X represents a benzyl group or a benzyloxyethyl group), and a carbazole derivative represented by the formula is provided.

Further, according to the present invention, the general formula

Embedded image (Wherein Ph represents a phenyl group, X represents a benzyl group or a benzyloxyethyl group), a carbazole derivative represented by the general formula

Embedded image (Wherein Ph has the same meaning as described above), a phenol, and carbon monoxide are reacted in the presence of a palladium catalyst and an organic base. Will be provided.

The carbazole derivative represented by the general formula (2) according to the present invention is a novel compound which has not been published in the literature.
This compound is prepared by using carbazole as a raw material, brominating it with bromine or N-bromosuccinimide as a brominating agent to give 3,6-dibromocarbazole, and then reacting it with benzyl chloride to give a compound of the general formula A carbazole derivative in which X in (1) is a benzyl group can be obtained. Further, by reacting 3,6-dibromocarbazole with 2-benzyloxyethyl p-toluenesulfonate, a carbazole derivative in which X in the general formula (1) is a benzyloxyethyl group can be obtained. In the benzylation reaction and the benzyloxyethylation reaction, after 3,6-dibromocarbazole was previously reacted with sodium hydride,
It can be carried out under mild conditions by reacting with benzyl chloride or 2-benzyloxyethyl p-toluenesulfonate.

The carbazole derivative represented by the general formula (1) is produced by reacting the carbazole derivative represented by the general formula (2), phenol, and carbon monoxide in the presence of a palladium catalyst and an organic base. However, it is not limited to this. In this case, the reaction between the carbazole derivative, phenol and carbon monoxide is represented by the following reaction formula.

[0010]

Embedded image (In the above formula, Ph and X have the same meanings as above)

In the carbazole derivative (I), the N-substituent X must be a benzyl group or a benzyloxyethyl group. Use of an acetyl group or a t-butyloxycarbonyl group as X does not give a good reaction result. In this case, in the carbonylation reaction, the acetyl group or t-butyloxycarbonyl group is eliminated, and an NH bond which causes the termination of polymerization is generated,
It becomes impossible to obtain a high molecular weight polyester.

The catalyst used in the carbonylation reaction is a palladium-phosphine complex. Examples of the palladium compound include palladium chloride, sodium palladium, inorganic salts such as potassium palladium, palladium acetate,
An organic complex such as palladium acetylacetonate, di (benzonitrile) palladium chloride, or π-allylpalladium chloride can be used.

As the phosphine, aromatic phosphines such as triphenylphosphine, tritolylphosphine and trianisylphosphine, alkylphosphines such as tributylphosphine and triisopropylphosphine,
1,2-bis (diphenylphosphino) ethane, 1,3
-Bis (diphenylphosphino) propane, 1,4-bis (diphenylphosphino) butane, 1,5-bis (diphenylphosphino) pentane, 1,6-bis (diphenylphosphino) hexane, 2,2′- Aromatic diphosphines such as bis (diphenylphosphino) ferrocene,
1,2-bis (dicyclohexylphosphino) ethane,
1,3-bis (dicyclohexylphosphino) propane, 1,4-bis (dicyclohexylphosphino) butane, 1,5-bis (dicyclohexylphosphino) pentane, 2,2′-bis (dicyclohexylphosphino)
And cyclohexyl-substituted diphosphines such as ferrocene.

The palladium-phosphine complex may be added to the reaction system as a pre-synthesized complex, or the palladium compound and phosphine may be charged into the reactor at a constant ratio to form a palladium complex under the reaction conditions. . On this occasion,
The ratio of phosphine to palladium (P / Pd atomic ratio) is 2
-10, preferably 3-5. The amount of the palladium compound used is 1 to 1 mol of the carbazole derivative.
/ 10 to 1/1000 mol, preferably 1/20 to 1/1
It is 00 mol.

The basic substance used in the present invention has an effect of remarkably promoting the reaction by trapping hydrogen halide produced by the reaction, and by adding it, the target compound can be efficiently obtained. You can Representative examples of the basic substance include aliphatic amines such as triethylamine, tributylamine and diisopropylethylamine, 1,8-diazabicyclo [5.4.0] -7-undecene, and 1,5-diazabicyclo [4.3. .0] -5
-Nonene, 1,4-diazabicyclo [2.2.2] octane, cyclic amines such as hexamethylenetetramine, N,
N, N ', N'-tetramethylethylenediamine, N,
Examples thereof include diamines such as N, N ', N'-tetramethylhexamethylenediamine, and aromatic amines such as N, N-dimethylaniline, pyridine, 2,6-lutidine, and 4-dimethylaminopyridine. Those having the highest activity for the polymerization reaction of the present method are cyclic amines such as 1,8-diazabicyclo [5.4.0] -7-undecene and 1,4-diazabicyclo [2.2.2] octane. The amount of these basic substances to be used is 2.0 to 4.0 mol, preferably 2.2 to 1 mol of the carbazole derivative.
２．５2.5 mol.

As the solvent used in the carbonylation reaction of the present invention, aromatic solvents such as benzene, toluene, xylene, chlorobenzene, fluorobenzene, anisole, p-dimethoxybenzene, m-dimethoxybenzene and o-dimethoxybenzene, dioxane, Ether-based solvents such as tetrahydrofuran and dimethoxyethane, chlorine-based solvents such as dichloromethane, dichloroethane and chloroform, or dimethylformamide and dimethylacetamide,
An amide-based solvent such as N-methyl-2-pyrrolidone or tetramethylurea, or dimethyl sulfoxide or the like is used.

The carbonylation reaction is carried out in the presence of carbon monoxide. Carbon monoxide is 0 to 50 kg / c in gauge pressure
It is adjusted to m ² , preferably 0 to 20 kg / cm ² . The reaction temperature is 100 ° C to 180 ° C, preferably 110 ° C.
~ 150 ° C. The reaction is usually carried out with stirring in a batch reactor, but is not limited thereto. Polyamide obtained as described above, after the reaction,
Since it is dissolved in the solvent, the catalyst, organic base and its hydrobromide salt can be removed by a known method. Further, it can be purified by a dissolution-reprecipitation method using a good solvent such as dimethylformamide.

[0018]

INDUSTRIAL APPLICABILITY The carbazole derivative of the present invention has excellent heat resistance and moldability and is suitable as a raw material for producing a soluble polyester. That is, by subjecting this carbazole derivative to polycondensation by polyesterification with a polyhydric alcohol such as ethylene glycol, a polyester having excellent heat resistance and moldability and being soluble can be obtained. According to the production method of the present invention, the carbazole derivative of the general formula (1) can be obtained in good yield.

[0019]

Next, the present invention will be described in more detail with reference to examples.

Reference Example 1 (Synthesis of N-benzyl-3,6-dibromocarbazole) 25.0 g of 3,6-dibromocarbazole (76.
9 mmol) of dimethylformamide (DMF) (80
ml) solution with 60 wt% sodium hydride 4.73 g
(118.5 mmol) was added little by little while stirring at room temperature.
Stir for minutes. Under ice cooling, 10.6 g of benzyl chloride
(83.7 mmol) was added dropwise over 5 minutes at room temperature to 1.5.
Stirred for hours. The reaction mixture was cooled, saturated aqueous ammonium chloride solution (50 ml) was added, the mixture was extracted with benzene (600 ml), the benzene layer was washed with water and saturated brine, and dried over sodium sulfate. The white solid obtained by concentration under reduced pressure was benzene (50 ml) -n-hexane (20
(ml) to give the desired product as colorless needle crystals (yield 27.7 g, yield 87%). Melting point 161.5-162.0 ° C Elemental analysis Calculated value C: 54.97%, H: 3.16
%, N: 3.37%. Found: C: 55.25%, H: 3.11%, N:
3.14%.

Reference Example 2 (Synthesis of N- (2-benzyloxyethyl) -3,6-dibromocarbazole) 3,6-dibromocarbazole 6.42 g (19.8 mmol) of DMF (50 ml)
1.19 g of 60 wt% sodium hydride (29.
7 mmol) little by little with stirring at room temperature, and after stirring for 5 minutes,
DM of 2-benzyloxyethyl p-toluenesulfonate
The F (50 ml) solution was added, and the mixture was stirred at 80 ° C. for 45 minutes. The reaction solution was cooled, and a saturated aqueous ammonium chloride solution (5
0 ml) to terminate the reaction, and benzene (600 m
After extraction in 1), the benzene layer was washed with water and saturated saline and dried over sodium sulfate. The white solid obtained by concentration under reduced pressure was converted into benzene (40 ml) -n-hexane (4%).
The crystals were recrystallized twice from 0 ml) to obtain the desired product as colorless needle crystals (yield 8.82 g, yield 97%). Melting point 149.0-150.0 ° C Elemental analysis Calculated value C: 54.93%, H: 3.73
%, N: 3.05%. Obtained value: C: 55.22%, H: 3.79%, N: 2.
80%.

Examples 1, 2 and Comparative Examples 1, 2 Various N-substituted compounds of 3,6-dibromocarbazole were synthesized in the same manner as in Reference Example 1, and phenol and monoxide were prepared as follows. Carbon reacted. N-substituted form of 3,6-dibromocarbazole (2.5 mmol), phenol 564.7 mg in 50 ml autoclave
(6.0 mmol), palladium chloride (PdCl ₂ ) 1
7.7 mg (0.1 mmol), triphenylphosphine 104.9 mg (0.4 mmol), and 1,8-
Diazabicyclo [5.4.0] -7-undecene 836
mg (5.5 mmol) was added to dimethylacetamide (7.
(5 ml), carbon monoxide was injected up to 10 kg / cm ² , and the mixture was vigorously stirred at 120 ° C. for 3 hours for reaction. After the reaction, excess carbon monoxide was removed, and the reaction solution was separated by column chromatography to obtain a carbazole derivative.

Table 1 shows the relationship between the raw material thus obtained and the yield of the obtained carbazole derivative.

[0024]

[Table 1]

From the results shown in Table 1, in the N-substituent X of the raw material carbazole derivative (I), X is —CH ₂ P.
h (benzyl) and _{- (CH 2) 2 OCH 2} Ph ( benzyloxycarbonyl ethyl) it is found to be stable to the carbonylation reaction. On the other hand, -COCH ₃ (acetyl) or -COO
It can be seen that C (CH ₃ ) ₃ (t-butyloxycarbonyl) is unstable with respect to the carbonylation reaction, and the carbonyl compound has an NH bond that causes the termination of polymerization.

 ──────────────────────────────────────────────────続 き Continued from the front page (72) Inventor Yoshihiro Sugi 1-1-1 Higashi, Tsukuba, Ibaraki Pref.

Claims (2)

(57) [Claims] 1. A compound of the general formula (In the formula, Ph represents a phenyl group and X represents a benzyl group or a benzyloxyethyl group). 2. A general formula: (Wherein Ph represents a phenyl group, X represents a benzyl group or a benzyloxyethyl group), to prepare a carbazole derivative represented by the general formula: A carbazole derivative represented by the formula (wherein X has the same meaning as described above), phenol, and carbon monoxide,
A method for producing a carbazole derivative, which comprises reacting in the presence of a palladium catalyst and an organic base.