Direct Generation of <i>N</i>‐Alkoxycarbonyl Nitrones from Oximes: Intramolecular Cycloaddition of Oximes Having Alkene Moieties
作者:Hiroto Sagara、Yoshio Suzuki、Nobuyoshi Morita、Shintaro Ban、Kosaku Tanaka、Ayaka Yamamoto、Yoshimitsu Hashimoto、Osamu Tamura
DOI:10.1002/adsc.202300793
日期:2023.11.21
δ,ϵ-Unsaturated oximes, on heating with O-alkyl S-(pyridin-2-yl)carbonothioates (PySCO2R) in refluxing toluene, undergo intramolecular cycloaddition to give N-alkoxycarbonylated multi-cyclic compounds. Mechanistic studies indicate that the reaction involves direct generation of N-alkoxycarbonyl nitrones followed by cycloaddition, instead of intramolecular oxime-olefin cycloaddition (IOOC) followed
δ,ε-不饱和肟与O-烷基S- (吡啶-2-基)硫代碳酸酯(PySCO 2 R)在回流甲苯中加热,发生分子内环加成,得到N-烷氧基羰基化多环化合物。机理研究表明,该反应涉及直接生成N-烷氧基羰基硝酮,然后进行环加成,而不是分子内肟-烯烃环加成(10OC),然后进行烷氧基羰基化。DFT计算表明肟与PySCO 2 R的N-烷氧基羰基化是协同反应。肟与手性烷氧基羰基化试剂的反应表现出相当高的非对映面选择性。