Process for production of optically active aminophosphinylbutanoic acids

A process for producing optically active aminophosphinylbutanoic acids represented by the formula (2):

• wherein R1 represents an alkyl group having 1 to 4 carbon atom(s), R2 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atom(s), R3 represents an alkyl group having 1 to 4 carbon atom(s), an alkoxy group having 1 to 4 carbon atom(s),
• an aryl group, an aryloxy group, or a benzyloxy group, and R4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atom(s);
• and * represents an asymmetric carbon atom, comprising asymmetrically hydrogenating a compound represented by the formula (1):
• wherein R1 represents an alkyl group having 1 to 4 carbon atom(s), R2 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atom(s), R3 represents an alkyl group having 1 to 4 carbon atom(s), an alkoxy group having 1 to 4 carbon atom(s), an aryl group, an aryloxy group, or a benzyloxy group, and R4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atom(s) in the presence of a ruthenium-optically active phosphine complex, wherein the optically active phosphine compound constituting the ruthenium-optically active phosphine complex is an optically active substance of phosphine represented by the formula (3):
• wherein each of R5, R6, R7, and R8 independently represents a phenyl group that may be substituted with a substituent selected from a group consisting of a halogen atom, a lower alkyl group, and a lower alkoxy group, a cyclopentyl group, or a cyclohexyl group, or the formula (4):
• wherein each of R9, R10, R11, and R12 independently represents a phenyl group that may be substituted with a substituent selected from a group consisting of a halogen atom, a lower alkyl group, and a lower alkoxy group, a cyclopentyl group, or a cyclohexyl group;
• R13, R14, 16, and 17 independently represent a hydrogen atom, an alkyl group, an alkoxy group, an acyloxy group, a halogen atom, a haloalkyl group, or a dialkylamino group, and R15 and R18 represent an alkyl group, an alkoxy group, an acyloxy group, a halogen atom, a haloalkyl group, or a dialkylamino group;
• two of R13, R14, and R15 may form a methylene chain that may have a substituent or a (poly)methylenedioxy group that may have a substituent and two of R16 and R17 and R18 may form a methylene chain that may have a substituent or a (poly)methylenedioxy group that may have a substituent;
• and further, R15 and R18 may form a methylene chain that may have a substituent or a (poly)methylenedioxy group that may have a substituent.