Palladium-Catalyzed Decarboxylative γ-Arylation for the Synthesis of Tetrasubstituted Chiral Allenes.

An enantiospecific palladium-catalyzed decarboxylative coupling of acyclic β,γ-alkynoic acids with various aryl iodides to chiral tetrasubstituted allenes is described. The coupling reaction comprises a decarboxylative γ-palladation of α,α-disubstituted carboxylic acids to provide the tetrasubstituted allenes with complete point-to-axial chirality transfer in excellent yields.