Studies in Silico-Organic Compounds. XXIII. Acyloxy Derivatives of the β-Chloroethyltrialkoxysilanes

Abstract

As far back as 1868, Friedel and Ladenburg (1) prepared a "new type" of orthoester, silicon tetraacetate, by the reaction of acetic acid with silicon tetrachloride. When the anhydride was used, acetyl chloride was a by-product. Acetate esters were later obtained by interchange of acetoxyl for alkoxyl using acetic anhydride (2), by replacement of bromine attached to silicon by acetate through the use of silver acetate (3), by slow prolonged boiling of acetate esters of the normal type with silicon tetrachloride (4), and by reaction of silicon tetrachloride with sodium acetate ( 5 ) . Montana (6) found that the tetraacetate decomposed into silicon dioxide and acetic anhydride. Excess silicon tetrachloride plus acetic anhydride gave acetyl chloride as a by-product. Tetraethoxysilane was found to react with propionic anhydride (7) yielding triethoxypropionoxysilane and diethoxydipropionoxysilane. Whitmore (8) arrived a t the acetate through the reaction of triethylsilanol with acetic anhydride. DISCUSSIOX