Manganese-Catalyzed Asymmetric Hydrogenation of Pyridyl Cyclic N-Alkyl Imines: A Direct Route to S-Nicotine and Derivatives

The asymmetric hydrogenation (AH) of cyclic N-alkyl imines offers an elegant and efficient method to afford chiral amines, especially for S-nicotine and its derivatives. However, this approach remains an ongoing challenge due to undesirable coordination of pyridyl-containing substrates to the active metal catalyst. Herein, we disclose a manganese-catalyzed AH that allows access to S-nicotine and other chiral α-(hetero)aryl pyrrolidines and provides an example of a base-metal catalyst that displays superior performance to its noble metal counterparts.