JPH0780894B2 - Method for producing arylsilanes - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing arylsilanes useful as a raw material in the organic silicon chemical industry.

[0002]

2. Description of the Related Art Conventionally, the following two methods are known as methods for producing arylsilanes. (1) A method of first preparing a corresponding nucleophilic species such as Grignard reagent or aryllithium from an aromatic halide, and then reacting this with a halosilane. (2) A method by a so-called Wurtz type heterocoupling reaction in which a halosilane and an aromatic halide are directly reacted with each other using an alkali metal. However, in (2), a homocoupling reaction between halosilanes or aromatic halides simultaneously proceeds as a side reaction of the heterocoupling reaction. Therefore, there are drawbacks that the selectivity of the product is low and the separation of the product is not easy. Further, in both methods (1) and (2), a large amount of salt is by-produced. Therefore, none of these methods is industrially advantageous.

[0003]

An object of the present invention is to provide a method for efficiently producing arylsilanes by a reaction under mild conditions without producing byproducts such as salts. To do.

[0004]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, arenes having at least one aromatic C—H bond and the following formula (I):
The present inventors have found that the hydrosilanes mentioned above produce a arylsilane by a rapid dehydrogenation reaction in the presence of a platinum compound under mild conditions, and have completed the present invention based on this finding. That is, the present invention is Ar-H
(However, Ar represents an aryl group.)
Aromatic compounds and formulas

[Chemical 3] (In the formula, R ¹ , R ² , R ³ and R ⁴ may be the same or different.
Optionally lower alkyl group, phenyl group or hydrogen
Indicates an atom. ) Hydrosilanes are represented by platinum
Formula, characterized by reacting in the presence of a compound

[Chemical 4] (In the formula, R ¹ , R ² , R ³ and R ⁴ and Ar are the same as above.
Have meaning. ) A method for producing arylsilanes
It provides the law .

Represented by Ar-H used in the present invention
The aromatic compound has an alkyl group, an alkoxy group,
It may contain an aryl group, an aryloxy group or a halogen atom as a substituent. Specific examples thereof include benzene, toluene, ethylbenzene, propylbenzene, hexylbenzene, o-xylene, m-xylene, p-xylene, naphthalene, 2-methylnaphthalene, anthracene, tetralin, biphenyl, anisole, diphenyl ether, butoxy. Examples thereof include benzene and chlorobenzene.

It is represented by the above formula (I) used in the present invention.
The hydrosilanes contained in the molecule are at least one Si-
It has an H bond. Illustrate these concretely
And 1,2 -bis (dimethylsilyl) benzene , 1,2
-Bis (phenylmethylsilyl) benzene and the like.

In the present invention, it is represented by the above Ar--H.
The reaction between the aromatic compound and the above-mentioned hydrosilanes is usually carried out in a molar ratio of both in the range of 1: 1 to 10,000: 1, preferably in the range of 50: 1 to 500: 1.

As the platinum compound used as a catalyst in the present invention, various conventionally known compounds can be used, but from the viewpoint of reaction rate, it is preferable to use a compound at least a part of which is soluble in the reaction system. preferable. As such a compound, a complex containing an organic ligand is particularly preferably used. Examples of preferred organic ligands include phosphines, phosphinites, phosphonites, phosphites, olefins, β-diketonato ligands, conjugated ketones, amines and carbon monoxide. Specific examples thereof include trimethylphosphine, tributylphosphine, triethylphosphine, tricyclohexylphosphine, triphenylphosphine, tri (p-tolyl) phosphine, tri (p-anisyl) phosphine, diphenylmethylphosphine and phenyldimethylphosphine. Cyclic phosphines such as chain phosphine, P-methylphosphorene, P-methylphosphole and 9-methyl-9-phosphabicyclo [4.2.1] nonane, 1,2-bis (dimethylphosphino) ethane, 1,3-bis (dimethylphosphino) propane, 1,4-bis (dimethylphosphino) butane, 1,2-bis (diphenylphosphino) ethane, 1,3-bis (diphenylphosphino) propane, 1, 4-bis (diphenylphosphino) butane, , 1'-Bis (dimethylphosphino) ferrocene, 1,1'-bis (diphenylphosphino) ferrocene, α, α'-bis (dimethylphosphino) -o-xylene and 1,2-bis (dimethylphosphino) ) Bisphosphines such as benzene, phosphinites such as methyl dimethylphosphinite and phenyldiphenylphosphinite, dimethyl methylphosphonite and dimethyl
Phosphonites such as phenylphosphonite, triethylphosphite, triphenylphosphite and phosphites such as 1-phospha-2,6,7-trioxa-4-ethylbicyclo [2.2.2] octane, ethylene,
Propene, cyclooctene, maleic anhydride, 1,5-
Hexadiene, 1,5-cyclooctadiene, 1,3-
Olefins such as cyclopentadiene, 2,5-norbornadiene and 1,3,5,7-cyclooctatetraene, dienes, β-diketonato ligands such as acetylacetonato, conjugated ketones such as dibenzylideneacetone, ethylenediamine and 2 , 2'-bipyridyl and the like.

Therefore, specific examples of the platinum compound preferably used in the present invention include (η-ethylene) bis (triphenylphosphine) platinum, tetrakis (diphenylmethylphosphine) platinum, dichlorobis (phenyldimethylphosphine) platinum and chlorohydrido. Bis (tributylphosphine) platinum, dichloro (tetramethylethylenediamine) platinum, dibromobis (triethylphosphite) platinum, bis (η-1,5-cyclooctadiene) platinum, dichloro (η-1,5-cyclooctadiene) platinum , Dicarbonylbis (tributylphosphine) platinum,
Carbonato bis (tricyclohexylphosphine) platinum, bis (dibenzylideneacetone) bis (triphenylphosphine) platinum, bis (dibenzylideneacetone)
Examples thereof include platinum and tris (dibenzylideneacetone) diplatinum, but are not limited thereto. Further, the above platinum compounds may be used alone or in combination of two or more kinds, and it is also possible to add the same or different organic ligand as that contained in the platinum compound together with the platinum compound, It is included in the preferred embodiments of the invention.

In the present invention, the amount of these platinum compounds used may be a so-called catalytic amount, which is a molar ratio to the hydrosilanes.
It is used in the range of 0.00001: 1 to 0.5: 1.
The organic ligand has a molar ratio to platinum atom in the platinum compound of 1: 1 to 20: 1, preferably 1: 1.
Used in the range of 1 to 4: 1.

In the present invention, the reaction can be easily carried out by using the aromatic compound represented by Ar--H itself in a large excess with respect to the hydrosilanes without using a solvent. However, the use of the solvent does not hinder the occurrence of the reaction, and the solvent can be used if necessary. The solvent is represented by Ar-H.
In consideration of the reactivity with aromatic compounds and hydrosilanes, those which do not react with these are selected. As such a solvent, a commonly used solvent, for example, a saturated hydrocarbon type solvent or an alkyl ether type solvent is preferable.

In the present invention, the reaction proceeds even at 0 ° C. or lower, but heating to a temperature of up to 250 ° C. is also possible in order to achieve a preferable reaction rate. Although it depends on the structure of the raw material, a generally preferred reaction temperature is in the range of 0 to 150 ° C.

Represented by the above formula (II) produced by the reaction
The arylsilanes thus obtained are easily separated from the reaction system by means usually used in organic chemistry such as distillation, recrystallization, chromatography, extraction with a solvent, or reprecipitation.

[0014]

The present invention will be described in more detail based on the following examples, but the present invention is by no means limited to these examples.

Example 1 0.003 of tris (dibenzylideneacetone) diplatinum
4 ml of a benzene solution containing 1 mmol of 1,2-bis (dimethylsilyl) benzene and 0.25 mmol of 1,2-bis (dimethylsilyl) benzene was heated to reflux for 120 hours under nitrogen to carry out the reaction. After concentration and distillation, 1-phenyldimethylsilyl-2-dimethylsilylbenzene was obtained in a yield of 82% with respect to the 1,2-bis (dimethylsilyl) benzene used. The elemental analysis values are as follows and were in good agreement with the theoretical values. C ₁₆ H ₂₂ Si ₂ Theoretical value: C 71.04%, H 8.20% Actual value: C 71.02%, H 8.03%

Example 2 A reaction was carried out in the same manner as in Example 1 except that heating was conducted at 110 ° C. for 84 hours in a sealed tube having an internal volume of 30 ml sealed under nitrogen at room temperature and 1 atm. Analysis by gas chromatography showed that 1-phenyldimethylsilyl-2-dimethylsilylbenzene was produced in a yield of 87% with respect to the 1,2-bis (dimethylsilyl) benzene used. .

Example 3 The reaction was carried out in the same manner as in Example 2 except that the heating time was 120 hours. After concentration and distillation, 1-phenyldimethylsilyl-2-dimethylsilylbenzene was found to be 86 relative to the 1,2-bis (dimethylsilyl) benzene used.
% Yield.

Example 4 Toluene was used instead of benzene, and the heating time was 4 times.
The reaction was performed in the same manner as in Example 1 except that the time was set to 8 hours. Analysis by gas chromatography revealed that 1-tolyldimethylsilyl-2-dimethylsilylbenzene was a mixture of positional isomers of the tolyl group (o: m: p = 18: 54: 2).
As 8), it was shown that the total yield was 84% with respect to the 1,2- (bisdimethylsilyl) benzene used. After the reaction mixture was concentrated and distilled, 1-tolyldimethylsilyl-2-dimethylsilylbenzene was converted to 62%.
% Yield. The elemental analysis values are as follows and were in good agreement with the theoretical values. C ₁₇ H ₂₄ Si ₂ Theoretical value: C 71.76%, H 8.50% Actual value: C 71.75%, H 8.34%

Example 5 Example 4 except that bis (cyclooctadiene) platinum was used instead of tris (dibenzylideneacetone) diplatinum.
The reaction was carried out in the same manner as described above and analyzed by gas chromatography. As a result, 1-tolyldimethylsilyl-2-dimethylsilylbenzene was a mixture of positional isomers of the tolyl group (o:
m: p = 17: 52: 31), it was shown that the product was produced in a total of 85% yield based on the 1,2-bis (dimethylsilyl) benzene used.

Example 6 A reaction was carried out in the same manner as in Example 4 except that (ethylene) bis (triphenylphosphine) platinum was used instead of tris (dibenzylideneacetone) diplatinum and the heating time was 24 hours. Analysis by gas chromatography revealed that 1-tolyldimethylsilyl-2-dimethylsilylbenzene was a mixture of positional isomers of the tolyl group (o: m:
p = 17: 50: 33), it was shown that the total yield was 4% with respect to the 1,2-bis (dimethylsilyl) benzene used.

Example 7 A reaction was carried out in the same manner as in Example 1 except that chlorobenzene was used instead of benzene and the heating time was 48 hours. When analyzed by gas chromatography, 1-
(Chlorophenyl) dimethylsilyl-2-dimethylsilylbenzene is a mixture of regioisomers of the chloro group on the chlorophenyl group (o: m: p = 59: 30: 11),
It was shown that the yield was 81% in total with respect to the 1,2- (bisdimethylsilyl) benzene used. The reaction mixture was concentrated and then distilled to give 1- (chlorophenyl) dimethylsilyl-2-dimethylsilylbenzene.
Obtained in 9% yield. The elemental analysis values are as follows,
It was in good agreement with the theoretical value. C ₁₆ H ₂₁ ClSi ₂ Theoretical value: C 63.02%, H 6.94% Actual value: C 63.16%, H 6.89%

Example 8 A reaction was carried out in the same manner as in Example 1 except that anisole was used instead of benzene and the heating time was 8 hours. Analysis by gas chromatography revealed that 1- (methoxyphenyl) dimethylsilyl-2-dimethylsilylbenzene was a mixture of regioisomers of the methoxyphenyl group (o:
m: p = 87: 10: 3), it was shown that the yield was 84% in total with respect to the 1,2- (bisdimethylsilyl) benzene used. When the reaction mixture was concentrated and then distilled, 1- (methoxyphenyl) dimethylsilyl-2-dimethylsilylbenzene was obtained in a 72% yield. The elemental analysis values are as follows and were in good agreement with the theoretical values. C ₁₇ H ₂₄ OSi ₂ Theoretical value: C 67.93%, H 8.05% Actual value: C 68.025, H 8.06%

[0023]

INDUSTRIAL APPLICABILITY According to the present invention, by reacting arenes having at least one aromatic C—H bond with hydrosilanes in the presence of a platinum compound under mild conditions, the organosilicon chemical industry can be used. Arylsilanes useful as raw materials and the like can be efficiently produced without salt by-products. Therefore, the industrial significance of the present invention is great.

Claims (1)

[Claims] 1. Ar—H (wherein Ar represents an aryl group)
Show. And an aromatic compound represented by the formula : (In the formula, R ¹ , R ² , R ³ and R ⁴ may be the same or different.
Optionally lower alkyl group, phenyl group or hydrogen
Indicates an atom. ) In the presence of a platinum compound.
A reaction of the formula : (In the formula, R ¹ , R ² , R ³ and R ⁴ and Ar are the same as above.
Have meaning. ) A method for producing an arylsilane represented by: