申请人:Bayer Aktiengesellschaft
公开号:US04824960A1
公开(公告)日:1989-04-25
A process for the preparation of a 1-aryl-5-amino-pyrazole of the formula ##STR1## in which Ar is in each case optionally substituted phenyl or pyridyl, comprising reacting an arylhydrazine of the formula Ar--NH--NH.sub.2 with acrylonitrile of the formula CH.sub.2 .dbd.CH--CN in a first stage in the presence of a diluent at a temperature between about 20.degree. C. and 100.degree. C. to form the arylhydrazine derivative of the formula Ar--NH--NH--CH.sub.2 --CH.sub.2 --CN, and in a second stage contacting such derivative with an oxidizing agent in the presence of a base at a temperature between about 0.degree. C. and 60.degree. C., thereby to effect oxidation and cyclization. The products are known intermediates for herbicides and insecticides.
一种制备式为##STR1##的1-芳基-5-氨基吡唑的方法,其中Ar在每种情况下是可选择取代的苯基或吡啶基,包括在第一阶段在稀释剂存在下以温度在约20℃至100℃之间反应式为Ar-NH-NH.sub.2的芳基肼和式为CH.sub.2.dbd.CH-CN的丙烯腈,以形成式为Ar-NH-NH-CH.sub.2-CH.sub.2-CN的芳基肼衍生物,以及在第二阶段在碱存在下以温度在约0℃至60℃之间将该衍生物与氧化剂接触,从而进行氧化和环化。该产品是除草剂和杀虫剂的已知中间体。