Application of HOF·CH3CN to the synthesis of glycosyl sulfones
摘要:
A fast, complete and clean conversion of thioglycosides into glycosyl sull'ones under mild acidic conditions is described, using the HOF center dot CH3CN complex at room temperature. This methodology affords glycosyl sull'ones in high yields and in excellent purity. (c) 2008 Elsevier Ltd. All rights reserved,
Efficient Palladium(0)-Catalyzed Synthesis of Alkenyl 1-Thioglycosides and Thiodisaccharides
摘要:
Unsaturated thiodisaccharides are obtained in good yields by alkylation of ethyl alpha-Q-Delta(2)-glycosides, having a leaving group at C-4, with various thiocarbohydrates in the presence of a catalytic amount of palladium(0). The reaction is regio- and stereospecific for the alpha-erythro enoside, and only stereospecific in the case of the alpha-threo enoside, alkylation occurring at C-4 and C-2. In all cases, only the beta-anomer is formed.