Catalytic Ugi-Type Condensation of α-Isocyanoacetamide and Chiral Cyclic Imine: Access to Asymmetric Construction of Several Heterocycles

作者：Liang Xia, Sheng Li, Ruijiao Chen, Kai Liu, Xiaochuan Chen · 发表于：The Journal of Organic Chemistry · 年份：2013 · DOI：10.1021/jo4000702 · 被引用次数：38 · 研究领域：Multicomponent Synthesis of Heterocycles、Synthesis and biological activity、Synthesis of Organic Compounds

Several novel heterocycles have been constructed asymmetrically on the basis of a catalytic Ugi-type condensation of α-isocyanoacetamide and chiral cyclic imine. The combination of phenylphosphilic acid and trifluoroethanol is exploited to promote an Ugi-type reaction with α-isocyanoacetamide for the first time. By means of this reaction, chiral 3-oxazolyl morpholin-2-one/piperazin-2-one derivatives are synthesized with high yields and excellent stereoselectivities. As electron-rich azadienes, these condensation products are further transformed to fused tricyclic frameworks by treatment with appropriate dienophiles such as maleic anhydride and unsaturated acyl chlorides via domino processes. Moreover, a one-pot, three-component synthesis of the chiral tricyclic frameworks from isocyanoacetamide, imine, and maleic anhydride is also feasible.