Solvent-Dependent Copper-Catalyzed Indolyl C3-Oxygenation and N1-Cyclization Reactions: Selective Synthesis of 3 H -Indol-3-ones and Indolo[1,2- c ]quinazolines

作者：Shenghai Guo, Fang Wang, Tao Li, Xinying Zhang, Xuesen Fan · 发表于：The Journal of Organic Chemistry · 年份：2018 · DOI：10.1021/acs.joc.8b00231 · 被引用次数：29 · 研究领域：Catalytic C–H Functionalization Methods、Quinazolinone synthesis and applications、Catalytic Cross-Coupling Reactions

A simple and practical procedure for the selective preparation of 3 H-indol-3-one and indolo[1,2- c]quinazoline derivatives through copper-catalyzed aerobic oxygenation and intramolecular cyclization reactions of 2-(2-amidoaryl)-1 H-indoles in the presence of acid has been disclosed. Interestingly, the reaction outcomes are exclusively dependent on the reaction medium employed. With DMF as the solvent, the amide moiety of indole substrates could act as an auxiliary to enable the indole's oxygenation reaction with molecular oxygen from air as the oxidant to give 3 H-indol-3-one derivatives in a highly selective manner. On the other hand, when the reactions were performed in 1,4-dioxane, the amide moiety switched to participate in an intramolecular indolyl N1-cyclization to afford indolo[1,2- c]quinazolines as the predominating products.