申请人:Takasago International Corporation
公开号:EP0322236A2
公开(公告)日:1989-06-28
A 2-N-acylaminoacetoacetic ester represented by the formula:
wherein R1 represents lower alkyl, or phenyl or benzyl each of which may be substituted with lower alkyl group or lower alkoxy; R2 represents hydrogen, a lower alkyl, lower alkoxy, or phenyl or benzyloxy, each of which may be substituted with lower alkyl or lower alkoxy, is dissolved in a solvent (e.g. an alkanol), mixed with a ruthenium-optically active phosphine complex as a catalyst, and hydrogenated at 25 to 50°C at a H2 pressure of 10-100 kg/cm2 for 15 to 48 hours, to obtain as an intermediate an optically active N-acyl threonine represented by:
wherein R1 and R2 are as defined above.
The intermediate (II) can be selectively prepared in a high yield and is then hydrolysed with HCI to obtain optically active threonine (CH3CHOHCHNH2COOH). Natural or non-natural type threonine can be prepared selectively by seleoting the absolute configuration of the ligand of the ruthenium-optically active phosphine complex, of which four general formulae are given, all containing a "BINAP" tertiary phosphine; syntheses of the catalyst are given.
一种 2-N-酰氨基乙酰乙酸酯,由式表示:
其中 R1 代表低级烷基,或苯基或苄基,它们各自可被低级烷基或低级烷氧基取代; R2 代表氢、低级烷基、低级烷氧基或苯基或苄氧基,它们各自可被低级烷基或低级烷氧基取代。例如烷醇)中,与作为催化剂的钌-光学活性膦络合物混合,并在 25 至 50℃、10-100 kg/cm2 的 H2 压力下氢化 15 至 48 小时,以获得光学活性 N-酰基苏氨酸作为中间体:
其中 R1 和 R2 如上定义。
中间体(II)可以选择性地以高产率制备,然后用 HCI 进行水解,得到光学活性苏氨酸(CH3CHOHCHNH2COOH)。通过选择钌-光学活性膦配合物配体的绝对构型,可以选择性地制备天然或非天然苏氨酸,其中给出了四个通式,均含有 "BINAP "叔膦,并给出了催化剂的合成方法。