Résumé
The first synthesis of beta-CF2-D-manno- and beta-CF2-D-galactopyranosylesters 1a and 1b is reported. It involves an oxidation-Reformatsky addition sequence on carbohydrate-derived diols and a dehydroxylation of the resulting cyclized compounds. The expected beta-CF2-D-glycoside and an undesired beta-CF2-L-glycoside are obtained from this sequence. An application of this methodology to the synthesis of some fluorinated pseudo-glycopeptides, potential selectin inhibitors, is also described.