State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratoryof Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China.
Chemistry. 2021 Apr 7;27(20):6308-6314. doi: 10.1002/chem.202005369. Epub 2021 Mar 5.
An external-photocatalyst-free, light-driven alkylative ring-opening of stable spiroindolines was developed to construct indolo- and benzoannulated eight-membered lactams. The spiroindolines were prepared from tetrahydro-β-carbolines by a dearomative Heck reaction. Mechanistic experimental studies on the alkylative ring opening suggested that a photoredox pathway was involved, in which the spiroindoline performed as both reagent and photosensitizer. DFT calculations showed that the radical addition toward a cyclic alkene was the key to the diastereoselective formation of tetracyclic medium-sized lactams.
发展了一种无需外加光催化剂、光驱动的稳定螺吲哚的烷基化开环反应，用于构建吲哚并和苯并稠合的八元内酰胺。螺吲哚啉由四氢-β-咔啉通过去芳构化 Heck 反应制备。烷基化开环的机理实验研究表明，涉及到一个光氧化还原途径，其中螺吲哚啉既是试剂又是光敏剂。DFT 计算表明，环状烯烃的自由基加成是立体选择性形成四环中到大环内酰胺的关键。
