Synthesis of trifluoromethylpyrrolopyrazole derivatives via [3+2] cycloaddition of trifluoromethyl N-acylhydrazones or trifluoroacetohydrazonoyl bromides with maleimides
作者:Yang Feng、Bo Chang、Yuanyuan Ren、Fangxia Zhao、Ke-Hu Wang、Junjiao Wang、Danfeng Huang、Xiaobo Lv、Yulai Hu
DOI:10.1016/j.tet.2023.133353
日期:2023.3
The methods give 3-trifluoromethylated pyrrolidino [3,4-c]pyrazolidin-4,6-dione and 3-trifluoromethylated dihydropyrrolo [3,4-c]pyrazole-4,6(1H,5H)-diones in good to excellent yields under mild reaction conditions. The 3-trifluoromethylated dihydropyrrolo [3,4-c]pyrazole-4,6(1H,5H)-diones can be smoothly oxidized to 3-trifluoromethylated pyrrolo [3,4-c]pyrazole-4,6(1H,5H)-diones by TCCA under mild reaction
从现成的三氟甲基结构单元(如三氟甲基 N-酰基腙或三氟乙酰肼基溴化物与马来酰亚胺)的 [3 + 2] 环加成反应,开发了一种高效实用的三氟甲基吡咯并吡唑衍生物制备方案。该方法得到 3-三氟甲基化吡咯烷并 [3,4- c ]pyrazolidin-4,6-dione 和 3-三氟甲基化二氢吡咯并 [3,4-c]pyrazole-4,6(1 H ,5 H )-diones在温和的反应条件下获得优异的产率。3-三氟甲基化二氢吡咯并[3,4- c ]吡唑-4,6(1 H ,5 H )-二酮可以顺利氧化为3-三氟甲基化吡咯并[3,4-c]pyrazole-4,6(1H,5H)-diones by TCCA under mild reaction conditions.