DEG0011214MA - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

Registration date: March 14, 1953 Advertised on June 14, 1956

GERMAN PATENT OFFICE

PATENT APPLICATION UNG

CLASS 12 ο GROUP 26 os

G 11214 IVb / 12o

Kurt Charles Frisch, Pittsfield, Mass., And Robert Bruce Young, Schenectady, N.Y. (V. St. A.)

have been named as inventors

General Electric Company, Schenectady, N.Y. (V. St. A.)

Representative: Dr.-Ing. A. von Kreisler, Dr.-Ing. K. Schönwald, Dipl.-Chem. Dr. phil. H. Siebeneicher and Dr.-Ing. T. Meyer, patent attorneys, Cologne 1

Process for the preparation of Tetraorganodihalogenäthinyldisilanen

The priority of registration in the V. St. v. Claimed America March 15, 1952

The invention relates to a process for the preparation of Tetraorganodihalogenäthinyldisilanen of the general formula

jl ——— V ^ f \ ^ / OI ~ ^ \ » ,

R,

in 'where R, R ₁ , R ₂ and R _{3 are} monovalent hydrocarbon radicals and X is a halogen atom. R, R ₁ , R ₂ and R ₃ can e.g. B. be: Aliphatic radicals including lower alkyl radicals (e.g. methyl, ethyl, propyl, isopropyl, butyl, hexyl and dodecyl), unsaturated aliphatic radicals (e.g. vinyl, allyl and methallyl) as well as cycloaliphatic radicals (e.g. Cyclopentyl, cyclopentenyl and cyclohexyl), aryl groups (e.g. phenyl, biphenyl and naphthyl), alkaryl groups (e.g. tolyl, xylyl and ethylphenyl), aralkyl groups (e.g. benzyl, phenylethyl and phenylbutyl) and their homologues. R, R ₁ , R ₂ and R ₃ can be the same or different. X can e.g. B. chlorine, bromine or fluorine.

609 530/485

G 11214 IVb / 12ο

According to the invention, a Grignard reagent of the general formula is used

Y-Mg-C = C-Mg-Y (II)

(Y equals halogen)

with a diorganodihalosilane whose organic substituents R, R ₁ , R ₂ and R ₃ correspond. The halogen in the Grignard reagent is preferably bromine and the halogen of the diorganodihalosilane is preferably chlorine.

Y-Mg-C = C-Mg —Y + 2RR ₁ SiX ₂ -

Disilanes, the two silicon atoms of which are linked by a phenylene group, have already been mentioned under Using a Di-Grignard reagent of the general formula X - Mg - R - Mg - X produced. It is also already known that in the reaction, the reaction of halogenated hydrocarbons with

Silicon halides in the presence of magnesium to monosilanes without the formation of a Grignard reagent the hydrocarbon substituents on the silane can contain acetylene bonds.

The diorganodihalosilari is added to the ethereal solution of the Grignard reagent, preferably is stirred at room temperature for a few hours and then the mixture for a longer time (about 2 to 6 hours) heated to reflux temperature. The salt which precipitates out during the reaction is advantageous filtered off, several times with an organic solvent, e.g. B. diethyl ether, washed, and then the filtrate and washing liquid are fractionally distilled. To avoid unwanted hydrolysis of the very Easily hy drolisier end, to exclude silicon-bonded halogen atoms and thus disruptions in the course of the reaction and loss of yield, must be carried out in all phases of the process under completely anhydrous conditions.

The acetylenedimagnesium dibromide is z. B. obtained from ethyl magnesium bromide and dry acetylene. After the reaction, excess acetylene is removed from the reaction mixture by means of nitrogen expelled. Then the acetylenedimagnesium dibromide layer, which is generally at the bottom

the vessel separates, separated. Ethylmagnesium bromide is made in the usual way from magnesium shavings represented in a large excess of ether and ethyl bromide.

The quantities (parts) are quantities by weight.

example

Ethylmagnesium bromide is made in a known manner from 96.8 g of magnesium shavings in 400 ecm of ether and 436 g of ethyl bromide in 1200 ecm of ether are shown.

The mixture is stirred vigorously until the reaction is complete. Then about 18 hours dry acetylene passed through the Grignard solution and then excess acetylene through Nitrogen expelled. Two layers have formed: greenish-black acetylenedimagnesium bromide at the bottom of the reaction vessel and an almost clear layer of ether on top. To the mixture of acetylene ■ dimagnesium dibromide and ether are stirred, in general, per mole of acetylenedimagnesium dihalide at least 2 moles, e.g. B. 2 to 4 or more moles, diorganodihalosilane to be used. The reaction is preferably in the presence of a catalyst, e.g. B. of powdered cuprous chloride, carried out, which is added to the ethereal solution of acetylenedimagnesium dihalide. The described The reaction should proceed according to the following equation:

2 MgXY + XRR ₁ Si - CE = C - SiRR ₁ X.

and cooling added 8 g of powdered cuprous chloride. This mixture is added with stirring to a solution of 774 g of dimethyldichlorosilane in 300 cc of ether in portions and refluxed for 3 ^χ / ₂ hours under reflux. The precipitate formed is filtered off, washed with ether, the filtrate and the washing liquid are combined, the ether is removed and the liquid which remains is fractionally distilled in vacuo. A colorless liquid which distills at 113 ^° and 65 mm Hg is obtained which, according to analysis, has tetramethyldichlorodisylethine of the formula

Cl (CHg) ₂ Si-CE = C-Si (CH ₈ ) ₂ Cl

is; Silicon content: found 27.29 ° / ₀ (theoretically go 26.54%)

By hydrolysis of the tetramethyldichlordisilyläthins with a saturated salt solution, its water content is greater than that required for the complete hydrolysis of the two chlorine atoms bonded to silicon, a colorless liquid is obtained that has a pleasant odor characteristic of silanols and tetramethyläthinyldisilandiol of the formula

HO (CHg) ₂ Si-C = C-Si (CHg) ₂ OH

is. Silicon content: 32.3% found, compared with a theoretical value of 32.2 ° / _0th

Other hydrolyzable organodisilylether compounds can also be prepared in a corresponding manner will. For example, methylphenyldichlorosilane and acetylenedimagnesium dibromide become dimethyldiphenyldichlorodisilylethine the formula

Cl (CH ₃ ) (C ₆ Hg) -Si-C = C-Si- (C ₆ H ₅ ) (CH ₃ ) Cl

educated. Correspondingly, other diorganodihalosilanes, z. B. diethyldibromosilane, methylethyldichlorosilane, methylbenzyldifluosilane and ethyltolyldichlorosilane, be reacted with a Di-Grignard reagent.

The acetylene group-containing silicon compounds according to the invention are as starting materials suitable for the manufacture of various polymeric products, which are used for insulation purposes or as dielectric Find material use.

The silicon compounds produced according to the invention can also be mixed with other substances such as styrene, butadiene, vinyl chloride, vinyl acetate, various acrylates and methacrylates, acrylonitrile etc., are copolymerized. The ability to

530/485

G 11214 IVb / 12ο

Polymerizing the addition of other compounds as a result of the triple compound is the case with silicon-containing compounds Polymerization products are important for silicone rubber to vulcanize faster or faster Achieve drying with silicone varnishes.

Tetraorganodisilyläthinverbindungen with silicon-bonded hydrolyzable groups can with advantage, e.g. B. with water, to be hydrolyzed to diol compounds, and the diols formed can

ίο on to polysiloxanes with disilylethine bonds polymerized, which are suitable for the production of silicone oils or alone or with others Organosiloxy units can be condensed into rubbers and plastics, which have good thermal stability have and additional interest because of their increased responsiveness due to the presence own the triple bond. Small amounts of the polysiloxanes can be used as additives to others unsaturated silicone synthetic resins with silicon-bonded hydrocarbon groups are used, which are copolymerizable or, through such additives, more easily in the infusible and insoluble State can be transferred.

Claims (1)

PATENT CLAIM: Process for the preparation of Tetraorganodihalogenäthinyldisilanen of the general formula R ₁ R ₂ X-Si-C = C-Si-X, in which X is halogen and R, R ₁ , R ₂ and R _{3 are} identical or different monovalent hydrocarbon radicals, characterized in that a Di-Grignard reagent of the general formula Y - Mg - C = C - Mg - Y, in which Y is halogen, is reacted with a diorganodihalosilane whose organic substituents R, R ₁ , R ₂ and R ₃ correspond. Cited publications: German Patent No. 853 350; British Patent No. 635 194.