Copper-Catalyzed Annulation Reaction of Alkenes and N‑Alkyl(aryl)-1-(methylthio)-2-nitroethenamine: an Approach for the Synthesis of Isoxazole Derivatives

A copper-catalyzed annulation reaction to access a variety of isoxazoles from alkenes and oxazete in situ generated from N-alkyl­(aryl)-1-(methylthio)-2-nitroethenamine was reported. A plausible mechanism underlying the formation of the product was proposed, which represented a new approach for the construction of isoxazolines. This reaction was capable of tolerating alkenes bearing various substituents, which showed a relatively broad substrate scope with good functional group compatibility.本文报道了一种铜催化环化反应，可由烯烃与由N-烷基（芳基）-1-(甲硫基)-2-硝基乙烯胺原位生成的恶丁环（oxazete）反应，合成多种异恶唑（isoxazoles）类化合物。本文提出了支撑该产物生成的合理反应机理，为异恶唑啉（isoxazolines）的构建提供了全新策略。该反应可兼容带有各类取代基的烯烃，展现出相对宽泛的底物适用范围与良好的官能团兼容性。