SU523100A1 - "Production method (bromomethyl) or (iodomethyl) -trichlorosilanes - Google Patents

Description

The invention relates to the field of organosilicon chemistry and concerns a method for the preparation of previously unknown and hard-to-reach (bromomethyl) - and (iodomethyl) trichlorosilanes of the type CHH251Cl3, where X Br, J.

These compounds can be widely used in silicone synthesis.

Classical methods for introducing bromine or iodine — direct halogenation or addition of hydrogen halides to alkenyltrichlorosilanes to produce (bromomethyl) - and (iodomethyl) trichlorosilanes are unacceptable.

The aim of the invention is to develop a method for producing previously unknown (bromomethyl- and (iodomethyl) trichlorosilanes, which serve as intermediates in the synthesis of biologically active silicon compounds and many other organic derivatives of this element.

They propose a process for the preparation of (bromomethyl) - or (iodomethyl) trichlorosilanes, which has no analogues in silica chemistry. It is based on the interaction of (chloromethyl) trichlorosilane with the corresponding aluminum halide in a low-boiling solvent, for example, ethyl bromide, methyl iodide, benzene, etc. The process can be carried out at room temperature when preparing bromo derivatives or if it is heated briefly - iodine derivatives. The reaction proceeds according to the scheme

ЗС1СН251С1з -} - А1Хз ЗХСН251С1з + А1С1з,

whereX Br, J.

By the same way, it is also easy to obtain (dibromomethyl) trichlorosilane Br2CH51Cl3 and alkyl (halomethyl) chlorosylapes of the type XCHzSiRnCls.-, where K CPS, CaH3; n, 2.

The proposed method can also be carried out on an industrial scale if elemental bromine (iodine) and powdered aluminum are used instead of aluminum halides.

(Bromomethyl) - and (iodomethyl) trichlorosilanes are heavy, fuming odorous liquids. They (bromo derivatives) are colorless or have a pinkish color (iodine derivatives). These compounds are easily converted to the corresponding haloalkyl trialkoxysilanes by the action of alcohols.

The structure of the obtained substances is proved by IR and PMR spectra, as well as their transformation into the corresponding (halo-methyl) trialkyloxysilanes, then converted into crystalline 1- (bromomethyl) - and 1- (iodomethyl) silatranes.

Example 1. (Bpoivi methyl) trichlorosilane.

A. In a three-necked flask equipped with a stirrer, a reflux condenser and a dropping funnel, a solution of 62.0 g (0.27 mol) of bromine aluminum in 150 ml of ethyl bromine is changed and 100.0 g (0.54 mol) added (chloromethyl a) trichlorosilane. The reaction mixture was not stirred for 2 hours at room temperature, replaced by a reflux condenser with a direct cooler and subjected to fractionated distillation. The yield of (bromomethyl) trichlorosilane is 92.5 g (75.4%): t. Cues. 133-135 ° C / 725 mm Hg v .; 1.4820;

cff 1,7558.

MRo 37.095; MRo calculated 37,232.

Found,% C 5.28; H 0.94; Si 12.02; C1 46.13; Br 35.03.

CHaSiClsBr.

Calculated,%: C 5.26; H 0.88; Si 12.3; C1 46.59; Br 34.99.

B. While stirring the mixture, 27.0 g (0.17 mol) of bromine, 3.0 g (0.11 mol) of powdered aluminum and 50 g (0.29 mol) of (chloromethyl) trichlorosilane in ethyl bromide for 2 hours at room temperature, 35.6 g (54.4%) of (bromomethyl) trichlorosilane are recovered; m.p. 133-135 ° C /

Hg v .; “20 1D820;

df

1.7558.

/ 725

mm

MRo 37.09; MRo calculated 37,232.

C 4.99; H 0.90;

Si 12.34; Found,%: CI 46.20; In 34,69.

CH SiClsBr.

C 5.26; H 0.88; 12.3; C1

Calculated,% 46.59; Br 34.99.

Example 2. (Dibromomethyl) trichlorosilane.

Similarly, from a solution of 18.7 g (0.07 mol) A1Bhz in 50 ml of ethyl bromide and 15.0 g (0.068 mol) of dichloromethyl trichlorosilane in 3 hours, 10.3 g (48.8%) (dibromomethyl) trichlorosilane is formed with t bales 184-186 ° С / / 720 mm Hg. Art. 1.5360; df 2.1832.

MRn 44.10; MRo calculated 44,946.

C 4.01; H 0.34;

Found,%: 35.08; Br 51.98.

CHSiClsBra.

Calculated%

C 3.98; H 0.32, 34.61, Br 52.01.

Example 3. (Yodm.: Il) trichlorosilane.

Similarly, out of 4.0 g (0.14 mol) of powdered aluminum, 56.0 g of iodine and 73.2 g (0.39 mol) of (chloromethyl) trhlorosilane in dry benzene (80 ml) form after heating for 2 hours 57 , 3 g (52.3%) (iodomethyl) trichlorosilane; Kil 166 - 167 ° С / 730 mm Hg. v .; ng 1.5338; df 2.0285.

MRn 42.18; MRo calculated 42.42.

Found,%: C 4.35; H 0.56; Si 10.18; J 46.09; C1 38.70.

CHaClaJSi.

Calculated; %:

C 4.36; H 0.36; Si 10.20; J 46.06; C1 38.62.

Example 4. (Bromomethyl) methyldichlorosilane.

Similarly, boiling for 2 hours in 30 ml of ethyl bromide mixture consisting of 11.0 g (0.04 mol) of aluminum bromide and 10.0 (0.06 mol) (chloromethyl) methyldichlorosilane gives 7.8 g (61.0%) (bromomethyl) methyldichlorosilane: m.p. 140-14GS / 730 mm Hg. v .; P 1,4761; Jf 1.5710; MRo 37.30; MRu is calculated 37.43.

Literary data; m.p. 140-141 ° C / / 740 Mivi RT. Art. p 1.4750; df 1.5700.

Example 5. (Iodomethyl) methyldichlorosilane.

Similarly, boiling (benzene, 2 hours), 2.8 g (0.0103 mol) of powdered aluminum, 41.0 g (0.161 mol) of metallic iodine and 50.14 g (0.306 mol) of (chloromethyl) methyldichlorosilane receive 23.2 g (29.7%) (iodomethyl) methyldichlorosilane with t. Kin. 169-170 ° С / / 750 mm Hg. Art., ng 1,528; df 1.8434.

MRo 42.58, MRo calculated 42.66.

Found,%: Si 10.93; J 50.02; Cl 27.71.

CaHsCbJSi.

Calculated,%: Si 11.02; J 49.78; Cl 27.81.

Claims (1)

Invention Formula The method of producing (bromomethyl) - or (iodomethyl) trichlorosilanes, characterized in that (chloromethyl) trichlorosilane is reacted with aluminum halide in a low boiling solvent medium, for example ethyl bromide.