DABCO-promoted highly diastereo- and regioselective construction of C-3 functionalized spirooxindoles <i>via</i> [3 + 2] cycloaddition of 2-aryl/heteroarylidene-1<i>H</i>-indene-1,3(2<i>H</i>)-diones with <i>N</i>-2,2,2-trifluoroethylisatin ketimines at ambient conditions
作者:Madavi S. Prasad、Sankar Bharani、Syed Mastan Sharief、Mudavath Ravi、Murugesan Sivaprakash、Biplob Borah、L. Raju Chowhan
DOI:10.1039/d2ra07141j
日期:——
The application of 2-aryl/heteroarylidene-1H-indene-1,3(2H)-dione as an activated olefin source in the DABCO-catalyzed [3 + 2] cycloaddition with N-2,2,2-trifluoroethylisatin ketimines has been disclosed. This highly efficient 1,3-dipolar cycloaddition reaction offered a variety of trifluoro methyl group bearing spiro-pyrrolidine linked oxindoles with four consecutive stereocentres in good to excellent
2-芳基/杂亚芳基-1H-茚-1,3( 2H )-二酮作为活化烯烃源在DABCO催化的N- 2,2,2-三氟乙基靛酮亚胺的[3+2]环加成反应中的应用已被披露。这种高效的 1,3-偶极环加成反应提供了多种带有螺吡咯烷连接的三氟甲基、具有四个连续立体中心的三氟甲基,具有良好至优异的产率和优异的非对映选择性。该方案的合成实用性是通过在室温下使用超低负载量的奎宁作为催化剂,展示具有两个邻位螺环季手性中心的螺环吡咯烷-羟吲哚的对映选择性结构,以良好的产率和优异的对映选择性(%3E90%ee)来建立的。 。