Takasago International Corporation

Takasago Perfumery Co., Ltd.

Takanao Taketomi

Hidenori Kumobayashi

Susumu Akutagawa

Noboru Sayo

Hidemasa Takaya

Kazushi Mashima

Ryoji Noyori

Tetsuo Ohta

Nobuo Yamada

Toshiyuki Takezawa

Toshiaki Sakaguchi

A process for preparing an optically active carnitine ester represented by formula (I):

Process for preparing optically active carnitine ester

An iridium-optically active phosphine complex represented by formula (I):

Iridium-optically active phosphine complex and process for producing

2,2'-Bis[di-(m-tolyl)phosphino]-1,1'-binaphthyl represented by formula (I) is disclosed. ##STR1## The compound of formula (I) is capable of forming a complex with a metal, e.g., ruthenium, rhodium, and palladium, which is extremely important and industrially excellent as a catalyst for various asymmetric synthesis reactions.

2,2'-bis(di-(m-tolyl)phosphino)-1,1'-binaphthyl

A process for preparing optically active threonine is disclosed, which comprises asymmetrically hydrogenating a 2-N-acylaminoacetoacetic ester represented by formula (I): ##STR1## wherein R.sup.1 represents a lower alkyl group, a phenyl group, a phenyl group substituted with a lower alkyl group or a lower alkoxy group, a benzyl group, or a benzyl group substituted with a lower alkyl group or a lower alkoxy group; R.sup.2 represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, a phenyl group, a phenyl group substituted with a lower alkyl group or a lower alkoxy group, a benzyloxy group, or a benzyloxy group substituted with a lower alkyl group or a lower alkoxy group, in the presence of a ruthenium-optically active phosphine complex as a catalyst to obtain an optically active threonine derivative represented by formula (II): ##STR2## wherein R.sup.1 and R.sup.2 are as defined above, and then hydrolyzing the compound of formula (II). The 2-N-acylaminoacetoacetic ester intermediate can be selectively prepared in a high yield. Either natural type threonine or non-natural type threonine can be prepared selectively by selecting the absolute configuration of the ligand of the ruthenium-optically active phosphine complex.

Process for preparing optically active threonine

A ruthenium-phosphine complex represented by formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom, a methyl group, or a methoxy group; and R.sup.2 represents a lower alkyl group, a halogenated lower alkyl group, a phenyl group, or a phenyl group substituted with a lower alkyl group. The complex is inexpensive and exhibits excellent performance as a catalyst for various organic syntheses, particularly for asymmetric hydrogenation.

Ruthenium-phosphine complex

A ruthenium-phosphine complex represented by formula (I): ##STR1## wherein R represents a hydrogen atom, a methyl group, or a methoxy group; and X represents ClO.sub.4, BF.sub.4, or PF.sub.6. The ruthenium-phosphine complex is inexpensive and exhibits excellent performance as a catalyst for various organic syntheses, particularly for asymmetric hydrogenation.

A ruthenium-phosphine complex represented by formula (I): ##STR1## wherein R represents a hydrogen atom, a methyl group, or a methoxy group; S represents a tertiary amine; when y is 0, then x is 2, z is 4, and p is 1; and when y is 1, then x is 1, z is 1, and p is 0. The complex is inexpensive and exhibits excellent performance as a catalyst for various organic syntheses, and particularly asymmetric hydrogenation.

A ruthenium-phosphine complex having a 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl or its derivative as a ligand and carboxyl groups bonded to the ruthenium atom thereof is disclosed. The complex is inexpensive and exhibits excellent performances as a catalyst for various organic syntheses, and particularly for asymmetric hydrogenation.

A process as described for preparing hydroxycitronellal by isomerizing certain 7-hydroxygeranylamine compound or 7-hydroxynerylamine compounds using a catalyst comprising a divalent palladium compound and a phosphine compound.

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Chiba, Japan

Takanao Taketomi