Borenium-Catalyzed Reduction of Pyridines through the Combined Action of Hydrogen and Hydrosilane
journal contributionposted on 12.08.2021, 16:06 by Joshua J. Clarke, Yuuki Maekawa, Masakazu Nambo, Cathleen M. Crudden
Mesoionic carbene-stabilized borenium ions efficiently reduce substituted pyridines to piperidines in the presence of a hydrosilane and a hydrogen atmosphere. Control experiments and deuterium labeling studies demonstrate reversible hydrosilylation of the pyridine, enabling full reduction of the N-heterocycle under milder conditions. The silane is a critical reaction component to prevent adduct formation between the piperidine product and the borenium catalyst.