Chiral copper complex catalyst composition and asymmetric production process using the same

A process for producing an optically active cyclopropane-carboxylic acid ester of formula (2):

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• wherein R3, R4, R5 and R6 are as defined below, and
• R7 represents
• an alkyl group having 1 to 8 carbon atoms,
• a cycloalkyl group which may be optionally substituted with a lower alkyl group,
• a benzyl group or phenyl group which may be optionally substituted with a lower alkyl group, a lower alkoxy group or a phenoxy group,
• which comprises the steps of:
• (a) contacting an optically active N-salicylideneaminoalcohol compound of formula (1):
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• with a mono-valent or di-valent copper compound, in an inert solvent,
• wherein R1 represents
• an alkyl group which may be substituted with a group selected from an alkoxy group, an aralkyloxy group, an aryloxy group, and cycloalkoxy group,
• an aralkyl, aryl or cycloalkyl group all of which may be substituted with a group selected from an alkyl group, an alkoxy group, an aralkyloxy group, an aryloxy roup, and a cycloalkoxy group,
• R2 represent
• a hydrogen atom, an alkyl group, a cycloalkyl group, or an aralkyl or phenyl group which may be substituted with a group selected from an alkyl group, an alkoxy group, an aralkyloxy group, an aryloxy group, and a cycloalkoxy group,
• X1 and X2 are the same or different and independently represent a hydrogen atom, a halogen atom, a nitro group, an alkyl group, an alkoxy group or a cyano group, and two adjacent X1 and X2 together with the benzene ring to which they are bonded may form a 1-hydroxy-2- or 2-hydroxy-1-naphthyl group, and
• the carbon atom denoted by “*” is an asymmetric carbon atom having either an S or R configuration, and
• the amount of the mono-valent or di-valent copper compound is less than 1 mole per 1 mole of the optically active N-salicylideneaminoalcohol compound of formula (1), and
• (b) reacting a prochiral olefin of formula (3):
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• wherein R3, R4, R5 and R6 independently represent
• a hydrogen atom,
• a halogen atom,
• a (C1-C10)alkyl group which may be substituted with a halogen atom or a lower alkoxy group,
• a (C4-C8)cycloalkyl group,
• an aryl group which may be substituted with a halogen atom, a lower alkyl group or a lower alkoxy group,
• R3 and R4, or R5 and R6 may be bonded at their terminals to form an alkylene group having 2-4 carbon atoms, and
• one of R3, R4, R5 and R6 groups represents an alkenyl group which may be substituted with a halogen atom, an alkoxy group or an alkoxy carbonyl group, of which alkoxy may be substituted with a halogen atom or atoms,
• provided that when R3 and R5 are the same, R4 and R6 are not the same,
• with a diazoacetic acid ester of formula (4):
• N2CHCO2R7 (4)
• wherein R7 is the same as defined above, in the presence of a chiral copper complex catalyst composition so produced in step (a).