申请人:TANABE SEIYAKU CO., LTD.
公开号:EP0808824A3
公开(公告)日:1998-04-08
A novel process for preparing optically active 2-halogeno-3-hydroxypropionic acid ester compound (III), which comprises reacting the aldehyde compound (I) with the silylketene acetal compound (II) in the presence of a chiral Lewis acid, as illustrated below.
wherein R is aryl, cycloalkyl, etc., one of X1 and X2 is H, and the other is Cl or Br, or both are Cl or Br, R1, R2 and R3 are the same or different, and are lower alkyl or aryl, R4 is lower alkyl or aryl, and * is asymmetric carbon atom. The compound (III) is very useful as an intermediate for preparing medicament such as diltiazem hydrochloride.
一种制备光学活性2-卤代-3-羟基丙酸酯化合物(III)的新工艺,包括在手性Lewis酸存在下,将醛化合物(I)与硅烯醚醛化合物(II)反应,如下所示。其中R为芳基、环烷基等,X1和X2中的一个为H,另一个为Cl或Br,或者两者均为Cl或Br,R1、R2和R3相同或不同,为低碳烷基或芳基,R4为低碳烷基或芳基,*为不对称碳原子。该化合物(III)作为制备地尔硫卓盐酸盐等药物的中间体非常有用。