| abstract |
Catalyst for the asymmetric (transfer) hydrogenation represented by the formula ML a X b S c , where M is a transition metal, to be chosen from rhodium and ruthenium, and X is a counter ion and S is a ligand, a ranges from 0.5 to 3 and b and c, each independently, range from 0 to 2, and L is a chiral ligand having the formula (1), where C n together with the two 2 O-atoms and the P-atom forms a substituted or non-substituted ring with 2-4 C-atoms, R 1 and R 2 each independently represent H, an optionally substituted alkyl, aryl, alkaryl or aralkyl group or may form a (heterocyclic) ring together with the N-atom to which they are bound. And a process for the asymmetric (transfer) hydrogenation of an olefinically unsaturated compound, ketone, imine or oxime derivate in the presence of a hydrogen donor and of a catalyst, use being made of a catalyst represented by formula ML a X b S c , where M is a transition metal, to be chosen from rhodium, iridium and ruthenium, X is a counter ion, S is a ligand, a ranges from 0.5 to 3 and b and c range from 0 to 2, and L is a chiral ligand having the formula (1), where C n together with the two 2 O-atoms and the P-atom forms a substituted or non-substituted ring with 2-4 C-atoms; and R 1 and R 2 are as defined above. |