Using DMF as Both a Catalyst and Cosolvent for the Regioselective Silylation of Polyols and Diols

Abstract

Highly regioselective silylation of primary hydroxyl groups of unprotected polyols and diols was obtained by the use of a mixed solvent of MeCN/DMF (10:1) in this study. DMF was discovered to be a good catalyst in this reaction, although the silylation using DMF as a solvent has been a common method for more than 40 years. The catalytic mechanism of DMF for the silylation was also proposed herein after intensive investigation of the reaction by NMR techniques. It has been demonstrated that a complex with a 1:1 ratio of the binding partners can be formed between TBSCl and DMF and has an association constant of 12/M, thus activating the silylation.