A highly efficient ruthenium-catalyzed asymmetric reductive amination (ARA) of racemic β-keto lactams with molecular hydrogen and ammonium salts is disclosed for the synthesis of enantiomerically pure primary amino lactams through dynamic kinetic resolution (DKR). By this approach, a range of syn primary β-amino lactams were obtained in high yields with high chemo-, enantio-, and diastereoselectivity (up to 98 % yield, 99 % ee, >20:1 d.r., syn products). The utility of the products has been demonstrated by rapid access to a key synthetic intermediate towards biologically active drug molecules. Meanwhile, mechanistic studies and control experiments indicate that the reaction may proceed through the hydrogenation of an iminium intermediate.

An iridium/f-amphol catalytic system for the enantioselective hydrogenation of α-substituted β-ketoesters via dynamic kinetic resolution is reported. The desired anti products were obtained in high yields (up to 98%) with good diastereoselectivity (up to 96:4 diastereometic ratio (dr)) and excellent enantioselectivity (up to >99% enantiomeric excess (ee)). A catalytic model is proposed to explain the stereoselectivity.

The direct catalytic asymmetric hydrogenation of (Z)-α-dehydroamino boronate esters was realized.

We herein report an iridium/f-ampha catalytic system for the asymmetric hydrogenation of aromatic α-keto esters.