Efficient enantioselective synthesis of CF2H-containing dispiro [benzo[b]thiophene-pyrrolidine-pyrazole]s via organocatalytic cycloaddition
作者:Yabo Deng、Changyan Yang、Siyu Shi、Yisheng Cao、Pengfei Jia、Yuan Li、Jinqi Huang、Wenjin Yan
DOI:10.1016/j.tet.2023.133580
日期:2023.9
An efficient and practical organocatalytic asymmetric [3 + 2] cycloaddition of difluoromethylated ketoimines and Pyrazolone derivatives catalyzed by quinine-derived thiourea has been disclosed. Under mild conditions, a broad range of CF2H-containing dispiro[benzo[b]thiophene-pyrrolidine-pyrazole]s bearing four adjacent chiral centers including two vicinal spiro quaternary stereocenters were obtained
公开了由奎宁衍生的硫脲催化的二氟甲基化酮亚胺和吡唑啉酮衍生物的有效且实用的有机催化不对称[3+2]环加成反应。在温和条件下,以良好的产率(66-96%产率)获得了多种含有CF 2 H的二螺[苯并[b]噻吩-吡咯烷-吡唑],其具有四个相邻的手性中心,包括两个邻位螺四元立构中心。中等至优异的非对映选择性 (82:18–95:5 dr ) 和对映选择性 (70–98% ee )。