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One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates
Published on: January 15, 2018
One-pot azidochlorination of glycals
Carolin Plattner1, Michael Höfener, Norbert Sewald
1Department of Chemistry, Organic and Bioorganic Chemistry, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
Abstract:
A simple one-pot azidochlorination for the preparation of nitrogen-containing Koenigs-Knorr glycosyl donors proceeds upon reaction of protected glycals with sodium azide, ferric chloride, and hydrogen peroxide. Different mono- and disaccharide galactals and glucals are converted in a highly α-selective manner to the 2-azido glycosyl chlorides. Starting from disaccharide galactals, building blocks for the synthesis of the T-antigen are obtained in a straightforward manner. The simplicity of the reaction conditions allows for an efficient and scalable α-selective synthesis of 2-azido substituted glycosyl chlorides.
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