Trimethylsilyl Triflate - Catalysid Acetal Formation Between Silylated Hexopyranosides and Methyl Pyruvate1

Abstract

Trimethylsilyl ethers of 2,3-di-O-substituted glycopyranosides or their thioglycopyranoside analogues were reacted with methyl pyruvate in the presence of trimethylsilyl triflate to give pyruvylated hexo-pyranosides in yields of 60–75%, and the ratio of the diastereoisomers was found to be ca. 1:1. The reaction can also be applied for cellobioside derivatives, providing suitable building blocks for the preparation of pyruvate-containing oligosaccharides.