Patent ID: 6858559

Claim:
An asymmetric copper catalyst composition comprising, as components, (a) an optically active bisoxazoline compound of formula (1): wherein R 1 and R 2 are different and each represents: a hydrogen atom, an alkyl group, a cycloalkyl group, or a phenyl or aralkyl group which may be substituted; R 3 and R 4 each represents a hydrogen atom, an alkyl group, a cycloalkyl group, or a phenyl or aralkyl group which may be substituted, or R 3 and R 4 are bonded to each other to form a C 3-5 cyclic alkylene group; and R 5 represents a hydrogen atom or a C 1-6 alkyl group, or the two R 5 groups are bonded to each other to represent a C 3-6 cyclic alkylene group; (b) a monovalent or divalent copper compound; and (c) a Lewis acid or a mixture of the Lewis acid and a strong acid that is selected from the group consisting of fluorosulfonic acid, chlorosulfonic acid, hydrogen fluoride, fuming sulfuric acid, and concentrated sulfuric acid.