The reaction of partially protected aldoses with (carbomethoxymethyl) triphenylarsonium bromide and zinc in toluene gave E α, β-unsaturated acyclic esters. When intramolecular transest erification occurred, bicyclic 1, 4-lactone derivatives were formed concurrently. Otherwise, using these non alcaline conditions, olefination did not favour the formation of C- glycosyl derivatives. On the other hand, when the reaction was performed with ( ...
