| abstract |
Chiral ligands of the formula I or II, may be obtained in high enantiomeric purity from compounds of the formulae III or IV, respectively, with suitable phosphines, where the symbols R<sub>1</sub>, R, n, R<sub>3</sub>, R<sub>4</sub>, R' are as described in claim 1. The products may be converted into transition metal complexes which are useful as catalysts for asymmetric hydrogenation reactions. |