Dual roles of ynoates: desymmetrization of dicarboxylic acids using trialkylamines as alkyl equivalents

A novel method has been developed for the desymmetrization of aromatic dicarboxylic acids by employing an esterification reaction/conjugate addition of a carboxyl group to ynoates, which can trigger a coupling reaction. This one-pot cascade transformation, utilizing trialkylamines as alkyl sources for esterification, and ethyl propiolate as a protective or coupling reagent for carboxyl functions (hydrolysis, amidation, esterification, and thioesterification), leads to an asymmetric dicarbonyl target skeleton in a selective manner.