Preparation of organosilanes
AssigneeDow Corning Corporation
InventorsRoland L. Halm, Kirk M. Chadwick, Brian R. Keyes
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Abstract
A process for the preparation of more highly alkylated silanes. The process comprises (A) contacting a halide of silicon, a silane or a disilane, with an alkyl halide in the presence of a metal, such as aluminum, which serves as a halogen acceptor, and a sufficient quantity of a catalyst effective in improving exchange of alkyl groups from the alkyl halide with said halogen atoms of the halide of silicon; (B) reacting the halide of silicon with the alkyl halide in the presence of the metal and the catalyst at a temperature greater than about 150.degree. C. to form the more highly alkylated silanes and a metal halide; and (C) isolating and separating the more highly alkylated silanes.
Claims17
A process for preparing more highly alkylated silanes having the formula,
- R.sub.a R.sup.i.sub.b SiX.sub.(4-a-b),
- wherein each R is independently selected from a group consisting of methyl, ethyl, and n-propyl;
- each R.sup.i is independently selected from a group consisting of hydrogen atoms, alkyl, substituted alkyl, alkenyl, aryl, and alkaryl groups;
- a has a value of 1, 2, 3, or 4, b has a value of 0, 1, 2, or 3, and the sum of a+b is 4 or less;
- and X is an independently selected halogen atom, said process comprising:
- (A) contacting a halide of silicon, having the formula,
- R.sup.i.sub.b SiX.sub.4-b,
- wherein R.sup.i, b, and X are defined above;
- with an alkyl halide, having the formula,
- RX,
- wherein R and X are defined above,
- in the presence of a metal which serves as a halogen acceptor and a sufficient quantity of a catalyst effective in improving exchange of said R groups from the alkyl halide with said halogen atoms X of said halide of silicon to yield said more highly alkylated silanes;
- (B) reacting the halide of silicon with the alkyl halide in the presence of the metal and the catalyst at a temperature greater than about 150.degree. C. to form the more highly alkylated silanes and a halide of the metal;
- and
- (C) isolating and separating the more highly alkylated silane.
Dependencies are inferred from the claim text.