Patent ID: 6277997
Filing Date: 2001-08-21
Classification: C07D

Abstract:
A process for producing a compound of formula I ##STR17##whereinR.sup.1 is lower alkyl or lower cycloalkyl;R.sup.2 is a 5- or 6-membered N-heterocyclic ring wherein (a) the ring is covalently bonded to the remainder of the compound via a linking N atom, (b) the ring contains 0, 1 or 2 additional hetero groups as ring members, selected from the group consisting of N, O and/or S, SO or SO.sub.2, (c) both ring atoms adjacent to the linking N atom are C, one or both of which are substituted by oxo, (d) the ring is either optionally benz-fused or optionally substituted by lower alkyl or oxo on one or more C atoms non-adjacent to the linking N atom; (e) the ring is optionally substituted by lower alkyl on one or more N atom(s) non-adjacent to the linking N atom by lower alkyl;comprising hydrogenating asymmetrically the corresponding compound of formula II ##STR18##in the presence of a catalytic amount of an optically active metal diphosphine complex which contains an optically active diphosphine ligand selected from the group consisting of an atropisomeric diphosphine ligand in the (R) stereoconfiguration; (R,R)-MeDuPHOS; (R,S)-PPF-P(pt Bu)2; and (R,S)-pCF.sub.3 -PPF-PPh.sub.2.