Direct reductive amination versus hydrogenation of intermediates -: A comparison

The direct reductive amination of acetophenone with benzylamine or piperidine was studied in comparison with the hydrogenation of possible intermediates like a corresponding imine or enamine. No common features in terms of productivity and stereo-control (in the case of chiral catalysts) have been found for both processes. Hence evaluation of effi-cient, selective and enantioselective catalysts for direct reductive amination appears to be a separate task.