Lewis acid-promoted cascade reaction for the synthesis of Michael acceptors and its application in a dimerization reaction

An efficient Lewis acid-promoted cascade reaction with dimethyl sulfoxide as a methylene source for the synthesis of Michael acceptors is reported. The key to developing this procedure is the selection of a mild base to modulate the equilibrium of various intermediates in order to drive the reaction forward to the formation of Michael acceptor and dimeric compound products. Extensive studies were performed to gain insight into a possible reaction mechanism.