Metal-free visible-light-driven cascade cyclization reaction to synthesize 2-oxindoles via benzoyl and phenylsulfinyl radicals with acrylamide derivatives.
Xin SunJing-Ping ZhuQing-Chuang QiuYa-Li HeDa-Rong HuXin-Ling LiGui-Ping LuYing-Hui YuanXiang-Fei ZhangXiaobo XuMiao YuBin WuPublished in: Organic & biomolecular chemistry (2022)
A metal-free visible-light-driven cascade cyclization reaction to synthesize 3-methyl-3-acetophenone-2-oxindoles and 3-methyl-3-(methylsulfonyl)benzene-2-oxindoles in yields up to 96% and 99%, via benzoyl and phenylsulfinyl radicals with acrylamide derivatives is reported, respectively. Extensive studies, including gram-scale, radical capture and isotope experiments, were performed to indicate that the reaction may involve a radical process.