Iridium-diphospine complexes and process for the hydrogenation of imines

摘要

Compounds of formulae I: (DIP)IrX.sub.q Y.sub.r (Z), Ia: (DIP) IrX. sub. s Y.sub.t (Z).sub.2 and Ib: (DIP)Ir(Z).sub.3 or mixtures of at least two of those compounds, wherein DIP is a ditertiary diphosphine, the two phosphine groups of which are bonded to a C.sub.2 -, C.sub.3 - or C.sub. 4 -carbon chain, with the result that the diphosphine forms a 5- to 7- membered ring together with the Ir atom, X is Cl, Br or I, Y is a hydrogen atom, q and r are 0, 1 or 2 and the sum of q+r is 2, s and t are 0 or 1 and the sum of s+t is 1, and Z is the anion of an organic oxy acid that contains a group C(O), S(O)O or P(O)O in the anion. The compounds are excellent catalysts for the hydrogenation of imines, especially for the enantioselective hydrogenation of prochiral imines.