An asymmetric reductive amination of ketones using both arylamines and benzhydrazide in the presence of nickel catalysts was developed. A one‐pot synthesis of tetrahydroquinoxalines was also developed starting directly from α‐ketoaldehydes and 1,2‐diaminobenzene. Formic acid was used as a safe and economic surrogate for high‐pressure hydrogen gas. Strongly σ‐donating bis(alkylphosphine)s are crucial
AbstractThe direct asymmetric reductive amination (DARA) of ketones with anilines is described by combining a chiral Brønsted acid (TRIP) and the non‐chiral Knölker iron complex as the catalyst system. In situ‐formed imines are reduced with molecular hydrogen to give chiral amines in high yields (90%) and enantioselectivities of up to 99% ee.magnified image