Method for preparing 1-alkyl-pyrazol-5-carboxylic acid esters III
    20.
    发明授权
    Method for preparing 1-alkyl-pyrazol-5-carboxylic acid esters III 有权
    1-烷基 - 吡唑-5-羧酸酯的制备方法

    公开(公告)号:US06444828B1

    公开(公告)日:2002-09-03

    申请号:US09762626

    申请日:2001-02-09

    IPC分类号: C07D23110

    CPC分类号: C07D231/14

    摘要: 1-Alkyl-pyrazole-5-carboxylic esters are obtained with surprisingly low proportions of 1-alkyl-pyrazole-3-carboxylic esters if a 2,4-diketo ester and/or an enolate thereof is reacted with an alkylhydrazine and/or a corresponding alkylhydrazinium salt, if appropriate, in the presence of a solvent and/or of water, in such a manner that during at least about 90% of the reaction free alkylhydrazine is present.

    摘要翻译: 如果2,4-二酮酯和/或其烯醇化物与烷基肼和/或烷基 - 吡唑-3-羧酸酯反应,则以非常低比例的1-烷基 - 吡唑-3-羧酸酯得到1-烷基 - 吡唑-5-羧酸酯 如果合适的话,在溶剂和/或水的存在下,使得在至少约90%的反应游离的烷基肼存在的情况下,相应的烷基肼鎓盐。