Efficient route to 2-deoxy beta-O-aryl-d-glycosides via direct displacement of glycosyl iodides
Son N Lam1, Jacquelyn Gervay-Hague
1Department of Chemistry, University of California, Davis, One Shields Ave., Davis, California 95616, USA.
Abstract:
[reaction: see text]. The conversion of glycals to 2-deoxy glycosyl acetates followed by reaction with trimethylsilyl iodide affords the corresponding glycosyl iodides, which readily undergo substitution with aryl alkoxy anions to provide 2-deoxy-beta-O-aryl glycosides. Direct displacement of the anomeric iodide alleviates the need to introduce temporary C-2 stereodirecting groups that require subsequent removal. The only observable byproducts from the glycosylations result from elimination of HI giving the starting glycals, which can be recycled through the reaction sequence.
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