SYNTHESIS OF α ,-BUTENOLIDE FROM R-OXO-α,B-UNSATURATED THIOESTERS

Abstract

Reaction of cis-r-oxo-a,b-unsaturated thioesters with sodiumdride, Grignard reagents, and allylsilanes at low temperature gave the r-substituted-a,b-butenolides. On the other hand, Reaction of the trans-r-oxo-a,b-unsaturated thioesters with sodium borohydride, Grignard reagents, and allylsilanes at low temperature gave the a,b-unsaturated thioesters. Reaction of the cis-r-oxo-a,b-unsaturated thioesters with silica gel gave the r-alkylidene-a,b- butenolides.