| abstract |
A process for producing an enantiomerically enriched compound of Formula I: n nwhere the R-configuration, or S-configuration at the stereogenic center is marked with an *; by hydrogenating an enamide of formula III:n n nin an organic solvent in the presence of a catalyst comprising a transition metal selected from rhodium or iridium, complexed to a chiral diphosphine ligand;n Ar is optionally substituted phenyl; Z is OR 1 , SR 1 or NR 1 R 2 ; and P is R 3 , OR 3 or NR 3 R 4 ; R 1 and R 2 are selected from H, C 1-8 alkyl, C 5-12 cycloalkyl, aryl and aryl-C 1-2 -alkyl; or R 1 and R 2 together with the nitrogen atom form a C 4-7 -membered heterocyclic ring optionally fused with a 5 - to 6 -membered carbocyclic or heterocyclic ring; and R 3 and R 4 are selected from H, C 1-8 alkyl, aryl, C 5-12 cycloalkyl and aryl-C 1-2 -alkyl; or R 3 and R 4 together with the nitrogen atom form a C 4-7 -membered heterocyclic ring. |