电化学炔烃氧化断键构建α-羰基芳酰胺衍生物的研究

Electrochemical oxidative cleavage of activated alkynes:a direct approach to carboxamide

在电化学条件下进行亚硝基苯与缺电子炔烃的偶联反应,实现了碳碳三键的断裂并生成α-羰基芳酰胺。反应在阴极单电子还原产生亚硝基自由基,随后对炔烃进行自由基加成并通过分子内重排断键一步合成α-羰基芳酰胺。通过对反应机理进行研究,表明α-羰基芳酰胺的氧来自于氧气。反应过程中使用氧气球提供氧气,10 mA恒定电流进行电解。该方法条件温和,操作简单,无需添加金属催化剂和额外的添加剂,具有良好的底物适用范围。

The coupling reaction of nitrosobenzene with electron-deficient alkynes under electrochemical conditions was reported.The carbon-carbon triple bond was broken andα-carbonyl aromatic amide was generated.The reaction produced nitroso radicals by cathodic single electron reduction,followed by free radical addition of alkynes and one-step synthesis ofα-carbonyl aromatic amide by intramolecular rearrangement of bonds.Through the study of the reaction mechanism,it was shown that the oxygen ofα-carbonyl aromatic amide came from oxygen.During the reaction,oxygen spheres were used to provide oxygen,and electrolysis was performed at a constant current of 10 mA to obtainα-carbonyl aromatic amide.For the method,it has mild conditions,simple operation,no need to add metal catalysts and additional additives,and has a good substrate scope.