Chemoselective Reduction of Tertiary Amides to Amines Catalyzed by Triphenylborane

Abstract

Triphenylborane (BPh₃ ) was found to catalyze the reduction of tertiary amides with hydrosilanes to give amines under mild condition with high chemoselectivity in the presence of ketones, esters, and imines. N,N-Dimethylacrylamide was reduced to provide the α-silyl amide. Preliminary studies indicate that the hydrosilylation catalyzed by BPh₃ may be mechanistically different from that catalyzed by the more electrophilic B(C₆ F₅ )₃ .