We report the synthesis of [M(PNP)(diene)](+) complexes (M = Ir or Rh; diene = COD or NBD), where PNP represents a tridentate diphosphine ligand of C-2 symmetry. These complexes are active catalysts for the hydrogenation of imines. Reduction of prochiral imines in the presence of chiral ligands leads to the corresponding amines with 7 to 55% ee. Copyright (C) 1996 Elsevier Science Ltd