The Preparation of Acetylated Silicic Acid by the Reaction of Silicic Acid with Acetyl Chloride

Abstract

The acetylation of silicic acid with acetyl chloride was investigated. The reaction was monitored by NMR spectroscopy and the products were characterized by IR spectra and by analysis of the acetoxyl group. The degree of acetylation was evaluated by the NMR spectroscopic analysis of the silylate of acetylated silicic acid revealing that acetyl chloride reacted readily with silicic acid. Acetylated silicic acid and its silylate had a low molecular weight. They were unstable and became insoluble after isolation. This indicates that acetyl chloride like chlorotrimethylsilane reacts with silicic acid without an appreciable change of the degree of polymerization of silicic acid.