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Updated: Dec 11, 2025

One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates
Published on: January 15, 2018
Straightforward synthesis of protected 2-hydroxyglycals by chlorination-dehydrochlorination of carbohydrate
Jan Choutka1, Michal Kratochvíl1, Jakub Zýka1
1Department of Chemistry of Natural Compounds, University of Chemistry and Technology, Prague, Technická 5, 166 28, Prague, Czech Republic.
Abstract:
A straightforward and scalable method for the synthesis of protected 2-hydroxyglycals is described. The approach is based on the chlorination of carbohydrate-derived hemiacetals, followed by an elimination reaction to establish the glycal moiety. 1,2-dehydrochlorination reactions were studied on a range of glycosyl chlorides to provide suitable reaction conditions for this transformation. Benzyl ether, isopropylidene and benzylidene protecting groups, as well as interglycosidic linkage, were found to be compatible with this protocol. The described method is operationally simple and allows for the quick preparation of 2-hydroxyglycals with other than ester protecting groups, providing a feasible alternative to existing methods.
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