摘要:
A process for producing a diphosphine oxide or diphosphonate represented by formula (1) as defined, which comprises treating, with a base, a phosphine compound represented by formula (2) as defined and adding the thus-treated phosphine compound to a nonpolar solvent having an oxidative metal compound suspended therein so as to effect dimerization. The present invention makes it possible to produce, conveniently, in a high yield and safely, a diphosphine oxide or diphosphonate which is an intermediate for producing a diphosphine compound useful as a ligand of a metal complex serving as a catalyst for asymmetric synthesis reaction.
摘要:
This invention provides a novel diphosphine compound which is useful as a ligand of catalysts for asymmetric synthesis reactions, particularly asymmetric hydrogenation reaction. Particularly, it provides a diphosphine compound represented by a general formula (1): wherein R1 and R2 each independently represents a cycloalkyl group, an unsubstituted or substituted phenyl group or a five-membered aromatic heterocycle residue.
摘要:
A novel process in which an optically active alcohol compound having a desired absolute configuration and a high optical purity can be obtained by asymmetrically hydrogenating a &bgr;-keto acid compound through a simple operation. An optically active alcohol represented by general formula (III) as defined is obtained by asymmetrically hydrogenating a &bgr;-keto ester compound represented by general formula (I) as defined in the presence of at least one ruthenium complex having as a ligand an optically active tertiary diphosphine compound represented by general formula (II) as defined.
摘要:
Disclosed is a ruthenium-phosphine complex usable as the catalyst giving a high enantiomer excess in an asymmetric reaction and a method for producing the complex. The ruthenium-phosphine complex is represented by formula (1): [{(RuX(L)}2(&mgr;-X)3]−[R22NH2]+ (1) wherein R2 represents hydrogen, alkyl, cycloalkyl or benzyl and L represents a diphosphine ligand represented by formula (2): wherein R1 represents an optionally substituted phenyl group and X represents a halogen atom. The method for preparing a ruthenium-phosphine complex represented by formula (1) is characterized in that a ruthenium complex represented by the formula [RuX(arene)(L)]X and an ammonium salt represented by the formula R22NH.HX are reacted with each other.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
The present invention provides a method for producing novel optically active diphosphine compounds �2,2'-bis(di-substituted phosphino)-1,1'-binaphthyl compounds! having a selectivity (chemoselectivity or enantioselectivity) and catalytic activity different from those of conventional BINAP compounds. In a method of the present invention for producing an optically active diphosphine compound (i.e., 2,2-bis(di-substituted phosphino)-1,1'-binaphthyl), 2,2'-bis(trifluoromethanesulfonyloxy)-1,1'-binaphthyl is reacted, in the presence of a transition metal-phosphine complex, with a phosphineoxide compound represented by the following general formula: A.sub.2 P(O)H wherein A represents a phenyl group; a mono- to tri-substituted phenyl group, wherein each substituent in the substituted phenyl group is individually selected from the group consisting of a halogen atom, a lower alkyl group, a lower alkoxy group or a lower halogenated-alkoxy group such that one or more of the substituents may be the same or different; a naphthyl group; a lower-alkyl naphthyl group; or a lower-alkoxy naphthyl group.
摘要:
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.
摘要:
A process for preparing an optically active 3-hydroxybutanoic acid represented by formula (I): ##STR1## wherein: R.sup.1 represents a protective group of carboxylic acid, andR.sup.2 represents a hydrogen atom; a lower alkyl group which may be substituted with a halogen atom; a lower alkoxy group; a phenyl group which may be substituted with a lower alkyl group or a lower alkoxy group; or a benzyloxy group which may be substituted with a lower alkyl group or a lower alkoxy group,is disclosed, comprising asymmetrically hydrogenating a 3-oxobutanoic acid ester represented by formula (II): ##STR2## wherein R.sup.1 and R.sup.2 are as defined above, in the presence of a ruthenium-optically active phosphine complex as a catalyst. The compound of formula (I) which is useful for synthesizing a 4-acetoxyazetidin-2-one derivative, a useful intermediate for obtaining penem antibiotics, can be prepared economically.