Bismuth-Catalyzed Amide Reduction.

In this article we report that a cationic version of Akiba's Bi(III) complex catalyzes the reduction of amides to amines using silane as hydride donor. The catalytic system features low catalyst loadings and mild conditions, en route to secondary and tertiary aryl- and alkylamines. The system permits that functional groups such as alkene, alkyne, ester, nitrile, furan, and thiophene remain intact. Kinetic studies on the reaction mechanism result in the identification of a reaction network with an important product inhibition that is in agreement with the experimental reaction profiles.