JPS5941997B2 - Manufacturing method of monohalogenosilane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method for producing monohalogenosilanes.

In recent years, monohalogenosilanes have been widely used as reaction reagents during the synthesis of pharmaceuticals or agricultural chemicals.

A known method for producing this monohalogenosilane is, for example, a method in which hexaorganodisiloxane and diorganodihalogenosilane are reacted in the presence of hexamethylphosphoric acid triamide or its hydrochloride; However, there was a problem in that the hexamethylphosphoric acid triamide or its hydrochloride used here is carcinogenic and must be handled with great care. The present invention aims to provide a method for producing monohalogenosilane that solves the problems of the conventional methods as described above, and is based on the general formula (wherein R is a hydrogen atom or a substituted or unsubstituted monohalogenosilane). This method is characterized in that a disiloxane represented by (representing a valent hydrocarbon group) and a diorganodihalogenosilane are reacted in the presence of 1,3-dimethyl-2-imidazolidinone or its hydrochloride.

To explain this, the present inventors have described a method for producing monohalogenosilane represented by the formula (here, R and As a result of extensive research,
For this purpose, we have discovered that it is extremely effective to react disiloxane and diorganodihalogenosilane in the presence of 1,3-dimethyl-2-imidazolidinone or its hydrochloride, and have completed the present invention. It is.

That is, in the present invention, since carcinogenic compounds are not used as in conventional methods, there are no problems in handling them, and therefore the desired monohalogenosilane can be produced extremely safely. Moreover, the remarkable effect that the target product can be obtained in high yield and economically is provided. Next, to explain the present invention in more detail, the disiloxane used as a starting material in the present invention is represented by the above general formula (), in which R is a hydrogen atom or a substituted or unsubstituted disiloxane. This monovalent hydrocarbon group includes alkyl groups such as methyl, ethyl and propyl groups, aryl groups such as phenyl and tolyl groups, and cyclohexyl groups such as cyclohexyl and cycloheptyl groups. Examples include alkyl groups and groups in which hydrogen atoms bonded to carbon atoms of these hydrocarbon groups are partially substituted with halogen atoms, cyano groups, and the like.

Note that the above R's do not necessarily have to be of the same type, but may be of different types.

Examples of such disiloxane include hexamethyldisiloxane, 1,1,3,3-tetramethyl-1,3
-divinyldisiloxane, 1,1,3,3-tetramethyldisiloxane, 1,1,3,3-tetramethyl-1.
3-di-n-butyldisiloxane, 1,1,3,3-tetramethyl-1,3-diethynyldisiloxane, 1,1
Examples include 3,3-tetraphenyl-1,3-dimethyldisiloxane and 1,1,3,3-tetramethyl-1,3-diphenyldisiloxane.

Further, in the present invention, examples of diorganodihalogenosilanes used as a starting material together with the above-mentioned disiloxane include dimethyldichlorosilane, methylvinyldichlorosilane, methylphenyldichlorosilane,
Examples include diphenyldichlorosilane and methylethyldichlorosilane.

In the present invention, the above-mentioned disiloxane and diorganodihalogenosilane are combined into 1,31-dimethyl-2-
The reaction is carried out in the presence of imidazolidinone or its hydrochloride, and it is usually preferable to use the disiloxane and diorganodihalogenosilane in equimolar proportions, but only one of them can be used. There is no problem even if the amount is excessive.

Further, 1,3-dimethyl-2-imidazolidinone or its hydrochloride is preferably used in an amount of 0.1 to 20% by weight based on the total weight of the disiloxane and diorganodihalogenosilane.

Furthermore, the reaction temperature is 0 to 200°C, preferably 10 to 200°C.
The temperature may be 100°C. In the present invention, disiloxane and diorganodihalogenosilane are reacted in the presence of 1,3-dimethyl-2-imidazolidinone or its hydrochloride under the above conditions, and then On the other hand, the solution remaining in the reactor undergoes a hydrolytic condensation reaction to produce a colorless and transparent silicone whose terminals are blocked with silyl groups. Oil can be obtained and used effectively.

Next, examples of the present invention will be given. Example 1 Internal volume 11? with stirrer, condenser and drip load. 1,3-dimethyl-2-imidazolidinone hydrochloride 10y1 hexamethyldisiloxane 486? (3 mol) and dimethyldichlorosilane 39
Add 7V (3.08 mol) and bring to room temperature while stirring.
After standing for 4 hours, distillation of trimethylchlorosilane was started.

Distillation was stopped when about 70% of the theoretical amount of trimethylchlorosilane was distilled out, the contents in the reaction vessel were ice-cooled, about 400 ml of water was added, stirred, and about 10 tons of activated clay was added. The mixture was mixed and filtered under reduced pressure. The organic layer of the filtrate was washed three times with water and treated with activated carbon and sodium carbonate to obtain 301y of dimethylpolysiloxane having a viscosity of 5 centistokes at 25°C. In addition, when the treatment was carried out in exactly the same manner as above except that the distillation was stopped when the amount of trimethylchlorosilane distilled reached about 80% of the theoretical amount, dimethylpolysiloxane with a viscosity of 6 centistokes at 25°C was obtained. was obtained for 270y.

Example 2 1,3-dimethyl 2-imidazolidinone 207 and hexamethyldisiloxane 486f (3
mol) and dimethyldichlorosilane 3977 (3.0
8 mol) was charged and reacted at 50° C. for 5 hours with stirring, and then distillation of trimethylchlorosilane from the reaction solution was started.

Distillation was stopped when 53% of the theoretical amount of trimethylchlorosilane had been distilled off, and the treatment was carried out in exactly the same manner as in Example 1 above, resulting in 4257 dimethylpolysiloxane having a viscosity of 2 centistokes at 25°C. Ta. Example 3 93.2y (0.52 mol) of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane, 4.7t of hydrochloride of 1,3-dimethyl-2-imidazolidinone, and dimethyl When 64.5 t (0.5 mol) of dichlorosilane was reacted at room temperature for 24 hours and distilled, 81.5 t of dimethylvinylchlorosilane was obtained.

Example 4 1,1,3,3-tetramethyldisiloxane 134.3
f (1 mol), 1,3-dimethyl-2-imitabridinone hydrochloride 8.0y and dimethyldichlorosilane 12
When 97 (1 mol) was reacted at 50° C. for 5 hours, 90.2y of dimethylchlorosilane was obtained.

Example 5 1,1,3,3-tetramethyl-1,3-diethynyldisiloxane 54.7t (0.36 mol), 1,3-dimethyl-2-imidazolidinone hydrochloride 2.4y and When 25.8y (0.2 mol) of dimethyldichlorosilane was reacted at room temperature for 24 hours, 52.57y of dimethylethynylchlorosilane was obtained.

Example 6 1,1,3,3-tetraphenyl-1,3-dimethyldisiloxane 65.3y (0.13 mol), 1,3-dimethyl-2-imidazolidinone hydrochloride 2.77y and dimethyldisiloxane When 25.8V (0.2 mol) of chlorosilane was reacted at room temperature for 48 hours, 12.1y of diphenylmethylchlorosilane was obtained.

Example 7 93.27 (0.5 mol) of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane, 4.4 t of hydrochloride of 1,3-dimethyl-2-imidazolidinone and diph When 126.5 t (0.5 mol) of enyldichlorosilane was reacted at room temperature for 8 hours and distilled, 90.17 g of dimethylvinylchlorosilane was obtained.

Claims (1)

[Claims] 1 Disiloxane and diorganodisiloxane represented by the general formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (wherein R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group) There are general formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ (in the formula, R is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group, and X represents a halogen atom).