Ruthenium(0)-sequential catalysis for the synthesis of sterically hindered amines by C–H arylation/hydrosilylation

Abstract

We report sequential ruthenium(0)-catalysis for the synthesis of sterically-hindered amines via direct C–H arylation of simple imines and imine hydrosilylation. The method involves direct C–H arylation under neutral conditions with organoboranes enabled by ruthenium(0) catalysis. The catalytic hydrosilylation was performed in a one-pot fashion using Et₃SiH. The reaction is compatible with a broad range of electronically- and sterically-varied imines, enabling rapid production of valuable biaryl amines in good to excellent yields. The method constitutes a two-step, one-pot procedure to synthesize sterically-hindered amines from aldehydes. The utility of this atom-economic strategy is demonstrated in one-pot, three-component coupling, direct in situ aldehyde arylation and the use of transfer hydrogenation.