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.