Patent ID: 7468459

Claim:
A process for preparing a compound of structural formula I: having the (R)- or (S)-configuration at the stereogenic center marked with an *; in an enantiomeric excess of at least 70% over the opposite enantiomer, wherein Z is OR 2 , SR 2 , or NR 2 R 3 ; R 1 is C 1-8 alkyl, aryl, heteroaryl, aryl-C 1-2 alkyl, or heteroaryl-C 1-2 alkyl; R 2 and R 3 are each independently hydrogen, C 1-8 alkyl, aryl, or aryl-C 1-2 alkyl; or R 2 and R 3 together with the nitrogen atom to which they are attached form a 4- to 7-membered heterocyclic ring system optionally containing an additional heteroatom selected from O, S, NH, and NC 1-4 alkyl, said heterocyclic ring being unsubstituted or substituted with one to three substituents independently selected from oxo, hydroxy, halogen, C 1-4 alkoxy, and C 1-4 alkyl wherein alkyl and alkoxy are unsubstituted or substituted with one to five fluorines; and said heterocyclic ring system being optionally fused with a 5- to 6-membered saturated or aromatic carbocyclic ring system or a 5- to 6-membered saturated or aromatic heterocyclic ring system containing one to two heteroatoms selected from O, S, and NC 0-4 alkyl, said fused ring system being unsubstituted or substituted with one to two substituents selected from hydroxy, amino, fluorine, C 1-4 alkyl, C 1-4 alkoxy, and trifluoromethyl; comprising the step of hydrogenating a prochiral enamine of structural formula II: in a suitable organic solvent in the presence of a transition metal precursor complexed to a chiral ferrocenyl diphosphine ligand of structural formula III: wherein R 4 is C 1-4 alkyl or aryl; R 5 and R 6 are each independently C 1-6 alkyl, C 5-12 cycloalkyl, or aryl; and R 7 is C 1-4 alkyl or unsubstituted phenyl.