Synthesis of Furanone-Fused 1,2-Benzothiazine by Rh(III)-Catalyzed C–H Activation: Regioselective Oxidative Annulation Leading to in Situ Lactonization in One Pot
作者:Vinayak Hanchate、Anil Kumar、Kandikere Ramaiah Prabhu
DOI:10.1021/acs.joc.9b01899
日期:2019.9.6
sulfoximine-directed C–H activation strategy catalyzed by a Rh(III)-catalyst leads to an efficient synthesis of furanone-fused 1,2-benzothiazine. In this reaction, cascade C–H activation, regioselective annulation, and lactonization occur in one pot. 4-Hydroxy-2-alkynoates, as coupling partners, form unsymmetrical alkynes, which undergo lactonization after C–H activation and regioselective annulation. The
由Rh(III)催化剂催化的由亚砜亚胺指示的CH活化策略可有效合成呋喃酮熔合的1,2-苯并噻嗪。在该反应中,一锅中发生级联的C–H活化,区域选择性环化和内酯化。4-羟基-2-炔酸酯作为偶联伙伴,形成不对称炔烃,在C–H活化和区域选择性环化反应后发生内酯化。该方法显示出良好的范围,具有广泛范围的亚砜亚胺和炔酸,并在以高收率形成单一区域异构体时显示区域选择性。