申请人:Takasago International Corporation
公开号:EP0339764A1
公开(公告)日:1989-11-02
A process for preparing carnitine comprising asymmetrically hydrogenating a γ-halogeno-β-keto ester represented by formula (I):
wherein X represents a chlorine atom or a bromine atom; and R represents a lower alkyl group,
in the presence of a ruthenium-optically active phosphine complex represented by formula (II), (III) or (IV):
Ru₂Cl₄(L)₂(C₂H₅)₃N (II)
Ru(OCOR²)₂(L) (IV)
RuX₂(L) (V)
wherein L represents 2,2′-bis(di-p-R¹-phenylphosphino)-1,1′-binaphthyl of formula (III):
wherein R¹ represents a hydrogen atom, a methyl group, or a t-butyl group;
R² represents a lower alkyl group or a trifluoromethyl group; and X is as defined above,
as a catalyst at a temperature of from 70 to 150°C to obtain an optically active alcohol represented by formula (VI):
wherein X and R are as defined above, and then reacting the optically active alcohol as obtained with trimethylamine without isolation.
一种制备肉碱的工艺,包括不对称氢化式 (I) 所代表的 γ-卤代-β-酮酯:
其中 X 代表氯原子或溴原子;R 代表低级烷基、
在式 (II)、(III) 或 (IV) 所代表的钌-光活性膦络合物存在下:
Ru₂Cl₄(L)₂(C₂H₅)₃N (II)
Ru(OCOR²)₂(L) (IV)
RuX₂(L) (V)
其中 L 代表式 (III) 的 2,2′-双(二-p-R¹-苯基膦)-1,1′-联萘:
其中 R¹ 代表氢原子、甲基或叔丁基;
R² 代表低级烷基或三氟甲基;X 如上定义、
作为催化剂,在 70 至 150°C 的温度下,得到由式 (VI) 代表的光学活性醇:
其中 X 和 R 如上文所定义,然后将得到的光学活性醇与三甲胺进行反应而不进行分离。