Enantioselective Rh/Cu-Catalyzed Addition of Terminal Alkynes to Allenes for the Synthesis of Chiral 1,4-Enynes

A regio- and enantioselective rhodium/copper-catalyzed coupling of readily available terminal alkynes and allenes is reported. This method enables direct, atom-economic access to chiral 1,4-enynes, a versatile class of compounds widely employed in the synthesis of natural products and pharmaceuticals. The transformation proceeds in high yields with excellent enantioselectivities and displays broad functional-group tolerance. The synthetic utility of the resulting products is further demonstrated through a range of downstream functionalizations that exploit the orthogonal reactivity of the alkyne and alkene moieties.