Mechanistic switch leading to highly efficient chirality transfer in Pd(0)-catalyzed coupling–cyclization of aryl iodides with 1∶1 acid–base salts of 2,3-allenoic acids and l-(−)-cinchonidine or d-(+)-/l-(−)-α-methylbenzylamine. Enantioselective synthesis of highly optically active 3-aryl polysubstituted butenolides

Abstract

An efficient methodology provides an easy access to highly optically active polysubstituted butenolides starting from aryl halides and 1:1∶salts of optically active 2,3-allenoic acid–base via an oxidative addition–coordinative cyclization–reductive elimination mechanism, which led to the high efficiency of this chirality isomerization reaction.