Process for preparing optically active alcohol

Claim 1

A process for preparing an optically active alcohol represented by formula (I): ##STR22## wherein R 1 and R 2 each represents an alkyl group having from 1 to 8 carbon atoms, a haloalkyl group, a hydroxyalkyl group, a trifluoromethyl group, a phenyl-substituted lower alkyl group, an alkoxycarbonyl-substituted lower alkyl group, a lower aminoalkyl group, a lower alkyl-substituted lower aminoalkyl group, a phenyl group, or a benzyloxy group; R 3 represents a hydrogen atom, a halogen atom, a lower alkyl group, or a lower alkoxycarbonyl group; or R 1 and R 2 , or R 2 and R 3 are taken together with the carbon atoms therebetween to form a 5- to 7-membered ring which may contain a lower alkoxycarbonyl group or a double bond, which comprises asymmetrically hydrogenating a 1/3-diketone represented by formula (II): ##STR23## wherein R 1 , R 2 , and R 3 are as defined above, in the presence of a ruthenium-optically active phosphine complex as a catalyst, wherein said ruthenium-optically active phosphine complex is a compound represented by formula (III): Ru.sub.x H.sub.y Cl.sub.z (R.sup.4 -BINAP).sub.2 (Q).sub.p (III) wherein R 4 -BINAP represents a tertiary phosphine represented by formula (IV): ##STR24## wherein R 4 represents a hydrogen atom, a methyl group, or a t-butyl group; Q represents a tertiary amine; when y represents 0, then x represents 2, z represents 4, and p represents 1; and when y represents 1, then x represents 1, z represents 1, and p represents 0, or a compound represented by formula (v): (RuH(R.sub.4 -BINAP).sub.v)Y.sub.w (V) wherein R 4 -BINAP is as defined above; Y represents ClO 4 , BF 4 , or PF 6 ; when e represents 0, then v represents 1, and w represents 2; and when e represents 1, then v represents 2, and w represents 1.