Tris(trimethylsilyl)silane-mediated Reductive Decyanation and Cyano Transfer Reactions of Malononitriles

Abstract

Reductive decyanation reactions of malononitriles were achieved with tris(trimethylsilyl)silane as a radical mediator. The reaction proceeds via a radical chain mechanism involving a silyl radical addition to the malononitrile to form an imidoyl radical followed by α-cleavage to give a silyl isocyanide and an α-cyano radical. The reaction of a 3-butenyl-substituted malononitrile afforded a decyano/cyanosilylation product in good yield through 1,4-cyano transfer.