Catalysis of the trifluoroethanolysis of dimethylphenylphenoxysilane

Abstract

The buffer-catalyzed trifluoroethanolysis of dimethylphenylphenorysilane was studied. The reaction exhibits general base catalysis, general acid catalysis, and bifunctional catalysis. The Bronsted values are the following: general base catalysis, β B =0.72; general acid catalysis, α A =0.65; bifunctional catalysis β AB =0. Solvent isotope effects for the acetic acid-tetramethylammonium acetate-catalyzed trifluoroethanolysis are greater than 1.0 for all three mechanisms of catalysis. It is suggested that general acid catalysis, general base catalysis, and bifunctional catalysis are modifications of a similar mechanism