Highly enantioselective aldehyde-nitroolefin Michael addition reactions catalyzed by recyclable fluorous (S) diphenylpyrrolinol silyl ether

A recyclable and reusable (S) diphenylpyrrolinol silyl ether I organocatalyst bearing a n-C8F17 fluorous tag has been demonstrated for promoting the asymmetric Michael addition reactions of a wide range of aldehydes with both aryl and alkyl-substituted nitroolefins and excellent levels of enantio- and diastereoselectivities are achieved. The catalyst I can be conveniently recovered by fluorous solid-phase extraction and subsequently reused (up to eight cycles) without significant loss of its catalytic activity and stereoselectivity for the process.