Ag-Catalyzed or Ag/PPh<sub>3</sub>-Catalyzed Chemoselective Switchable Cascade Reactions of <i>N</i>-Propargyl Thiocarbamoyl Fluorides and Malonate Esters
作者:Zhongliang Cai、Junyi Zhou、Miao Yu、Liqin Jiang
DOI:10.1021/acs.orglett.1c03950
日期:2022.1.14
The divergent chemoselective synthesis of 2-methylene-2,3-dihydrothiazoles and 4-benzylidene pyrrolidine-2-thiones (most with E stereoselectivity) from N-propargyl thiocarbamoyl fluorides and malonate esters in moderate to excellent yields with a broad substrate scope and functional group tolerance has been accomplished. AgNTf2 catalyst at 60 °C in dichloroethane provided 4-benzylidene pyrrolidine-2-thiones
从N-炔丙基硫代氨基甲酰氟和丙二酸酯以中等至优异的产率,具有广泛的底物范围和功能性,不同的化学选择性合成 2-亚甲基-2,3-二氢噻唑和 4-亚苄基吡咯烷-2-硫酮(大多数具有 E 立体选择性)群体容忍度已经完成。AgNTf 2催化剂在 60 °C 下在二氯乙烷中提供 4-亚苄基吡咯烷-2-硫酮。AgOTf 催化剂和 PPh 3配体在回流乙腈中导致形成的 α,α-二酯硫代酰胺中间体的反应性发生完全转换,随后异构化得到 2-亚甲基-2,3-二氢噻唑。