作者:Yihui Xu、Qiaoling Chen、Yishi Tian、Wei Wu、Yi You、Zhiqiang Weng
DOI:10.1016/j.tetlet.2019.151455
日期:2020.1
A silver-catalyzed synthesis of 5-aryl-3-trifluoromethyl pyrazoles from reaction of various N'-benzylidene tolylsulfonohydrazides with ethyl 4,4,4-trifluoro-3-oxobutanoate is described. The reaction proceeds via sequential nucleophilic addition, intramolecular cyclization, elimination, and [1], [5]-H shift steps to afford the trifluoromethylated pyrazole products in moderate to excellent yields. The
描述了由各种N'-亚苄基甲苯磺酸磺酰肼与4,4,4-三氟-3-氧代丁酸乙酯反应的银催化的5-芳基-3-三氟甲基吡唑的银催化合成。反应通过连续的亲核加成,分子内环化,消除和[1],[5] -H转变步骤进行,以中等至极好的收率得到三氟甲基化的吡唑产物。该反应与多种官能团相容。