Highly Regioselective Allylic Alkylation of Dienyl Acetates and Enynyl Acetates Catalyzed by an Iridium Complex

Abstract

An efficient catalyst for allylic alkylation of dienyl and enynyl acetates, [{Ir(cod)Cl}2] (cod=cycloocta-1,5-diene) catalyzes the regioselective nucleophilic attack at the substituted allylic terminus to give a branched product in high selectivity. These results suggest the intermediacy of a 1-(1-alkenyl)- and 1-(1-alkynyl)π-allyliridium species, respectively (see scheme).