Cobalt‐Catalyzed Transfer Hydrogenation of α‐Ketoesters and N ‐Cyclicsulfonylimides Using H ₂ O as Hydrogen Source

A Co‐catalyzed effective transfer hydrogenation of various α‐ketoesters and N ‐cyclicsulfonylimides by safe and environmentally benign H 2 O as hydrogen source is described. The reaction used easily available and easy to handle zinc metal as a reductant. Interestingly, the catalytic system does not require ligand for reduction of N ‐cyclicsulfonylimides. magnified image