SYNTHESIS OF CHIRAL ESTERS OF ACETYLENEDICARBOXYLIC ACID

A general method for the preparation of acetylenedicarboxylic acid est ers has been investigated and several esters have been prepared in exc ellent yield. The bis-(methyl (S)-lactyl), bis-(methyl (R)-mandelyl), and bis-menthyl esters were prepared, as well as achiral diaryl and di alkyl esters. The esters were synthesized from the corresponding dibro mofumarates by 23-dibromo elimination using zinc or zinc amalgam in TH F at room temperature or at reflux. The dibromofumarates were prepared by the esterification of dibromofumaryl chloride with the correspondi ng alcohols.