| abstract |
Compounds of the formula II n ncan be hydrogenated to the corresponding butane derivatives in the presence of homogeneous cataslysts composed of metal salts or complexes containing metals selected from the group consisting of Rh, Ir, and Ru and preferably containing diphosphine ligands, with, in addition, excellent optical yields being achieved when one of R 2 and R 3 is not a hydrogen atom and the diphosphine ligand is chiral. |