Regioselective synthesis of 6-trifluoromethyl-1,4,5,6-tetrahydropyrazolo[3,4-b]pyran derivatives
作者:Dongmei Li、Liping Song、Shaodi Song、Shizheng Zhu
DOI:10.1016/j.jfluchem.2007.04.004
日期:2007.8
two-step procedure for the synthesis of 6-(trifluoromethyl)-1,4,5,6-tetrahydropyrazolo[3,4-b]pyran derivatives (4) from the reaction of 4-arylidene-3-methyl-1-phenyl-5-pyrazolones (1) with ethyl trifluoroacetoacetate (2), a versatile fluorinated building-block, was presented. Furthermore, to increase the efficiency of this reaction, the more convenient one-pot three-component process was also developed
从4-亚芳基-3-甲基-1的反应合成6-(三氟甲基)-1,4,5,6-四氢吡唑并[3,4- b ]吡喃衍生物(4)的简便两步程序提出了具有多功能氟代砌块的三氟乙酰乙酸乙酯(2)的-苯基-5-吡唑啉酮(1)。此外,为了提高该反应的效率,还开发了一种更方便的单锅三组分方法,其收率略低。用P 2 O 5处理4,浓缩。H 2 SO 4,POCl 3 / Py或p在剧烈条件下的-TsOH没有得到相应的脱水产物。