Regioselective synthesis of allylic/propargylic alcohols from conjugated dienes/enynes catalyzed by CuCl under aerobic conditions

An effective method for the regioselective synthesis of allylic/propargylic alcohols from conjugated dienes/enynes with the CuCl/HBpin system under air is described herein. This reaction features mild conditions, excellent regioselectivity and broad substrate scope, as various aryl, hetero-aryl and alkyl group-substituted allylic alcohols were successfully obtained in moderate to good yields. A plausible mechanism was proposed, in which the reaction was initiated with hydride transformation to the conjugated dienes/enynes following Markovnikov's rule. Then, the atmospheric O₂ inserted into the C-[Cu] bond, and subsequent hydrogenation by HBpin afforded the desired alcohol.