Process for the preparation of optically active cyclopropane carboxylic
acids
    1.
    发明授权
    Process for the preparation of optically active cyclopropane carboxylic acids 失效
    光学活性环丙烷羧酸的制备方法

    公开(公告)号:US4508919A

    公开(公告)日:1985-04-02

    申请号:US555187

    申请日:1983-11-25

    CPC分类号: C07C51/487

    摘要: The invention relates to a process for the preparation of enantiomers of trans vinyl-cyclopropane carboxylic acids of the formula I, ##STR1## wherein R is a methyl group or chlorine atom, by resolution of racemic trans compound or mixture of racemic cis and trans compounds by using (+)- or (-)-N-(1-formamido-2,2,2-trichloroethyl)-piperazine as a resolving agent in a polar solvent then separating the crystallizing salt of (+)-trans carboxylic acid and (-)-resolving agent or (-)-trans carboxylic acid and (+)-resolving agent from the mother liquor by filtration and obtaining the enantiomers by acidifying the mother liquor or the salts suspended in water followed by extraction with a solvent and evaporation.The products so obtained may be used as starting materials for the preparation of insecticides.

    摘要翻译: 本发明涉及通过拆分外消旋反式化合物或外消旋的顺式和反式化合物的混合物制备式I的反式乙烯基 - 环丙烷羧酸的对映异构体的方法,其中R是甲基或氯原子 通过在极性溶剂中使用(+) - 或( - ) - N-(1-甲酰胺基-2,2,2-三氯乙基) - 哌嗪作为拆分剂,然后将(+) - 反式羧酸的结晶盐和 ( - ) - 拆分剂或( - ) - 反式羧酸和(+) - 拆分剂通过过滤从母液中获得对映异构体,通过酸化母液或悬浮在水中的盐,然后用溶剂萃取并蒸发 。 所得产物可用作制备杀虫剂的起始原料。