| abstract |
Compounds of general formula I or Ia <IMAGE> (I) <IMAGE> (Ia) or mixtures thereof, wherein the groups P-L-P are a ligand from the group comprising diphosphine and diphosphinite, in which the secondary phosphine groups or phosphinite groups P are coupled via 2 to 4 C atoms, and which form a 5-, 6- or 7-membered ring with the Ir atoms, X, X1, X2, X3, X4, X5 and X6 independently of the others are Cl, Br or I, or X1 and X6 and H and X2, X3, X4 and X5 independently of the others are Cl, Br or I, or X1 and X5 and H and X2, X3, X4 and X6 independently of the others are Cl, Br or I, and M(+) is an alkali metal cation or quaternary ammonium. The compounds are suitable as homogeneous catalysts for the (preferably) asymmetric hydrogenation of N-substituted imines to secondary amines. |