Abstract: A process for preparing an optically active carnitine ester represented by formula (I): wherein R represents a lower alkyl group; and X represents a halogen atom, is disclosed, comprises asymmetrically hydrogenating a &ggr;-trimethylammonium-3-oxobutanoic ester halide represented by formula (II): wherein R and X are as defined above, in the presence of a ruthenium-optically active phosphine complex as a catalyst. An optically active carnitine ester of any desired isomerism can be obtained through simple operation in high yield at high optical purity. The substrate used is easily available.

Abstract: Disclosed is a 2-phenyl-2-(2'-piperidinylidene)acetate derivative suitably used for a raw material of a 2-phenyl-2-(2'-piperidinyl)acetate derivative and a process for manufacturing the same. Also disclosed is a process for manufacturing an optically active 2-phenyl-2-(2'-piperidinyl)acetate derivative which is a major intermediate for an antidepressant. The 2-phenyl-2-(2'-piperidinylidene)acetate derivative is manufactured by cyclizing a 7-(N-substituted amino)-3-oxo-2-heptanoate derivative. The optically active 2-phenyl-2-(2'-piperidinyl)acetate derivative is manufactured by asymmetrically hydrogenating the 2-phenyl-2-(2'-piperidinylidene)acetate derivative in the presence of a complex of a Group VIII transition metal or an acid.

Abstract: The present invention provides a ligand for a novel catalyst superior in such characteristics as selectivity (chemoselectivity and enantioselectivity) and catalytic activity in asymmetric synthesis reactions and a ligand for a novel catalyst effective in an asymmetric hydrogenation reaction in particular. The ligand is an optically active diphosphine compound represented by the following formula: ##STR1## where Ph is a phenyl group, X is a chlorine or bromine atom, and R.sup.1 and R.sup.2 are each an alkyl group having 1 to 3 carbon atoms.

Abstract: A process for preparing optically active 4-hydroxy-2-pyrrolidone comprising asymmetrically hydrogenating an N-substituted-4-amino-3-oxobutanoic ester represented by formula (I): ##STR1## wherein R.sup.1 represents a benzyloxycarbonyl group, the benzene ring of which may be substituted; and R.sup.2 represents a lower alkyl group having 1 to 4 carbon atoms, in the presence of a ruthenium-optically active phosphine complex as a catalyst to obtain an optically active N-substituted-4-amino-3-hydroxybutanoic ester, deblocking, and cyclizing the ester. A series of the reactions can be carried out in one pot.

Abstract: A phosphine-phosphinite compound represented by formula (I): ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, each represent a substituted or unsubstituted phenyl group or a substituted or unsubstituted naphthyl group, and a process for preparing a 4-?(R)-1'-formylethyl!azetidin-2-one derivative using the compound (I). The compound (I), either in combination, or as a complex, with a transition metal compound, is useful as a catalyst for asymmetric hydroformylation and makes it possible to easily synthesize an important intermediate for carbapenem antibiotics or a precursor thereof at high regioselectivity and diastereo-selectivity.

Abstract: A novel chiral unsymmetric diphosphine compound of formula (I): ##STR1## wherein Ar.sup.1 and Ar.sup.2, which are different from each other, each represent a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a pyridyl group, a quinolyl group, an isoquinolyl group, a furfuryl group, a benzofurfuryl group, a thienyl group, or a benzothienyl group, and a transition metal complex containing the diphosphine compound as a ligand. The complex catalyzes various asymmetric synthesis reactions, e.g., asymmetric hydrogenation or asymmetric hydrosilylation, exhibiting excellent performance in selectivity, conversion and catalytic activity, to provide a product of desired absolute configuration at high optical purity and in high yield.

Abstract: Disclosed is a 7-(N-substituted amino)-3-oxo-2-phenylheptanoate derivative, 7-(N-substituted amino)-3-hydroxy-2-phenylheptanoate derivative, and 7-(N-substituted amino)-3-benzenesulfonyloxy-2-phenylheptanoate derivative, which are quite important major intermediates for an antidepressant. The 7-(N-substituted amino)-3-oxo-2-phenylheptanoate derivative can be manufactured by condensing an enolate of phenylacetates with a 5-(N-substituted amino) pentanoate derivative.

Abstract: A 1-substituted-2-diphenylphosphinonaphthalene represented by formula (I): ##STR1## wherein at least one of R.sup.1, R.sup.2, R.sup.3, and R.sup.4, which may be the same or different, represents a lower alkyl group having 1 to 4 carbon atoms which may be substituted with an alkoxy group, a phenyl group or --OR.sup.6 (wherein R.sup.6 represents a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms or an alcohol-protective group), and the rest of them represent a hydrogen atom; A represents a single bond or a methylene group; and R.sup.5 represents a substituted or unsubstituted phenyl group; and a transition metal complex comprising the 1-substituted-2-diphenylphosphinonaphthalene as a ligand. The transition metal complex is useful as a catalyst in asymmetric synthesis.

Abstract: A novel process for preparing an optically active amine by asymmetric hydrogenation of an imine compound, such as an imine compound prepared by condensing benzylamine and acetophenone, in the presence of a catalytic amount of an iridium-optically active phosphine complex and benzylamine or a benzylamine derivative. The present invention provides an optically active amine of high optical purity.

Abstract: Disclosed herein is a process for producing a (2S,5S)-2,5-diamino-1,6-diphenyl-3-hexanone derivative represented by the formula (1): ##STR1## wherein R.sup.1 means a lower alkylcarbonyl group, a halogen-substituted lower alkylcarbonyl group, an arylcarbonyl group or a lower alkoxycarbonyl group, and R.sup.2 and R.sup.3 are identical with or different from each other and denote individually an aryl group or an alkoxy-substituted aryl group, which comprises subjecting a (2S)-2,5-diamino-1,6-diphenyl-4-hexen-3-one derivative represented by the formula (2): ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 have the same meaning as defined above, to a hydrogenation reaction in the presence of a transition metal-containing catalyst.

Abstract: A process for preparing a 4-acyloxyazetidinone or a derivative thereof represented by formula (IV): ##STR1## wherein R.sup.1 represents a hydrogen atom, a lower alkyl group, a hydroxyethyl group, or a protected hydroxyethyl group; R.sup.3 represents an alkyl group having from 1 to 10 carbon atoms which may be substituted with a halogen atom, a cyano group, a lower alkoxy group or a phenyl group, or a substituted or unsubstituted phenyl group, provided that the .alpha.-positioned carbon atom of said alkyl group should not have more than two halogen atoms; and R.sup.4 represents a hydrogen atom, a lower alkyl group, or a lower alkoxycarbonyl group, which is useful as an intermediate for penem antibiotics is disclosed, comprising reacting azetidinone or a derivative thereof represented by formula (II): ##STR2## wherein R.sup.1 is as defined above, and R.sup.2 represents a hydrogen atom, a lower alkyl group, a lower alkoxycarbonyl group, or a carboxyl group, with a carboxylic acid represented by formula (III):R.

Abstract: A process for preparing a 4-acyloxyazetidinone or a derivative thereof represented by formula (IV): ##STR1## wherein R.sup.1 represents a hydrogen atom, a lower alkyl group, a hydroxyethyl group, or a protected hydroxyethyl group; R.sup.3 represents an alkyl group having from 1 to 10 carbon atoms which may be substituted with a halogen atom, a cyano group, a lower alkoxy group or a phenyl group, or a substituted or unsubstituted phenyl group, provided that the .alpha.-positioned carbon atom of said alkyl group should not have more than two halogen atoms; and R.sup.4 represents a hydrogen atom, a lower alkyl group, or a lower alkoxycarbonyl group, which is useful as an intermediate for penem antibiotics is disclosed, comprising reacting azetidinone or a derivative thereof represented by formula (II): ##STR2## wherein R.sup.1 is as defined above, and R.sup.2 represents a hydrogen atom, a lower alkyl group, a lower alkoxycarbonyl group, or a carboxyl group, with a carboxylic acid represented by formula (III):R.

Abstract: Compounds represented by the following general structural formula (1) and methods for producing the compounds: ##STR1## R.sup.1 represents a group such as benzyloxycarbonyl, R.sup.2 represents a lower alkyl group, R.sup.3 represents a hydrogen atom or a protecting group, each of M.sup.1 and M.sup.2 represents a metal atom, and n represents the atomic valence of M.sup.1. Intermediates for HMG-CoA reductase inhibitors can be prepared safely and easily from these compounds.

Abstract: A process for preparing an optically active (2S,3S)-allophenylnorstatin derivative (I) is disclosed, comprising asymmetrically hydrogenating a 4-phenyl-2-halogeno-3-oxobutyric ester (III) in the presence of a ruthenium-phosphine complex to obtain a 4-phenyl-(2S)-halogeno-(3R)-hydroxybutyric ester (IV), epoxidizing the ester (IV) in the presence of a base to obtain a 4-phenyl-(2S,3R)-epoxybutyric ester (V), reacting the ester (V) with a tri(lower alkyl)silylazide or a (lower alkyl)diarylsilylazide in the presence of a Lewis to obtain a (3S)-azido-4-phenyl-(2S)-trisubstituted silyloxybutyric ester (VI), hydrogenolyzing the ester (VI) into a (2S,3S)-allophenylnorstatin derivative (VII), protecting the amino group of the compound (VII), and, if desired, hydrolyzing the compound before or after the amino group protection. Compounds (I) can be obtained at high optical purity safely and in good yield.

Abstract: A process for the production of an optically active carboxylic acid (I), which comprises subjecting an olefinic carboxylic acid (II) to asymmetric hydrogenation using a complex as a catalyst consisting of an optically active phosphine (III) and a ruthenium compound.Complex of ##STR1## with a ruthenium compound ##STR2## According to the process of the present invention, optically active carboxylic acids can be produced with high yield.

Abstract: A phosphine compound represented by one of the formulas: ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, each represent a phenyl group or a phenyl group substituted with a halogen atom or a lower alkyl group or taken together form a divalent hydrocarbon group; and R.sup.3 and R.sup.4, which may be the same or different, each represent a lower alkyl group, a phenyl group or a phenyl group substituted with a halogen atom, a lower alkyl group or a lower alkoxy group or taken together form a divalent hydrocarbon group, and wherein R.sup.6 and R.sup.6' which may be the same or different, each represent a hydrogen atom, a lower alkyl group or a lower alkoxy group; R.sup.5, R.sup.5', R.sup.11 and R.sup.11' which may be the same or different, each represent a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom; or a pair of R.sup.5 and R.sup.6 or a pair of R.sup.5' and R.sup.6' may form a ring; R.sup.7 and R.sup.

Abstract: Disclosed herein is a process for producing a (2S,5S)-2,5-diamino-1,6-diphenyl-3-hexanone derivative represented by the formula (1): ##STR1## wherein R.sup.1 means a lower alkylcarbonyl group, a halogen-substituted lower alkylcarbonyl group, an arylcarbonyl group or a lower alkoxycarbonyl group, and R.sup.2 and R.sup.3 are identical with or different from each other and denote individually an aryl group or an alkoxy-substituted aryl group, which comprises subjecting a (2S)-2,5-diamino-1,6-diphenyl-4-hexen-3-one derivative represented by the formula (2): ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 have the same meaning as defined above, to a hydrogenation reaction in the presence of a transition metal-containing catalyst.

Abstract: A process for for producing a (2R,3S)-cyclohexylnorstatine or a salt thereof is disclosed, which comprises the steps of: enantioselectively hydrogenating a 4-cyclohexyl-2-halogeno-3-oxobutyric acid ester in the presence of a ruthenium-phosphine complex to produce a 4-cyclohexyl-2-halogeno-(3R)-hydroxybutyric acid ester (2); epoxidizing the compound (2) in the presence of a base to produce a 4-cyclohexyl-(2S,3R)-epoxybutyric acid ester (3); reacting the compound (3) with a lower trialkylsilyl azide in the presence of a Lewis acid to produce a (3S)-azide-4-cyclohexyl-(2S)-substituted butyric acid ester (4); subjecting the compound (4) to hydrogenolysis to produce a (2S,3S)-cyclohexylnorstatine derivative (5); and inverting the configuration at the 2-position of the compound (5).

Abstract: A process for for producing a (2R,3S)-cyclohexylnorstatine or a salt thereof is disclosed, which comprises the steps of: enantioselectively hydrogenating a 4-cyclohexyl-2-halogeno-3-oxobutyric acid ester in the presence of a ruthenium-phosphine complex to produce a 4-cyclohexyl-2-halogeno-(3R)-hydroxybutyric acid ester (2); epoxidizing the compound (2) in the presence of a base to produce a 4-cyclohexyl-(2S,3R)-epoxybutyric acid ester (3); reacting the compound (3) with a lower trialkylsilyl azide in the presence of a Lewis acid to produce a (3S)-azide-4-cyclohexyl-(2S)-substituted butyric acid ester (4); subjecting the compound (4) to hydrogenolysis to produce a (2S,3S)-cyclohexylnorstatine derivative (5); and inverting the configuration at the 2-position of the compound (5).

Abstract: A process for preparing a 4-acyloxyazetidinone or a derivative thereof represented by formula (IV): ##STR1## wherein R.sup.1 represents a hydrogen atom, a lower alkyl group, a hydroxyethyl group, or a protected hydroxyethyl group; R.sup.3 represents an alkyl group having from 1 to 10 carbon atoms which may be substituted with a halogen atom, a cyano group, a lower alkoxy group or a phenyl group, or a substituted or unsubstituted phenyl group, provided that the .alpha.-positioned carbon atom of said alkyl group should not have more than two halogen atoms; and R.sup.4 represents a hydrogen atom, a lower alkyl group, or a lower alkoxycarbonyl group,which is useful as an intermediate for penera antibiotics is disclosed, comprising reacting azetidinone or a derivative thereof represented by formula (II): ##STR2## wherein R.sup.1 is as defined above, and R.sup.2 represents a hydrogen atom, a lower alkyl group, a lower alkoxycarbonyl group, or a carboxyl group,with a carboxylic acid represented by formula (III):R.