A Radical-Initiated Fragmentary Rearrangement Cascade of Ene-Ynamides to [1,2]-Annulated Indoles via Site-Selective Cyclization
作者:Sifan Li、Yu Wang、Zibo Wu、Weiliang Shi、Yibo Lei、Paul W. Davies、Wei Shu
DOI:10.1021/acs.orglett.1c02519
日期:2021.9.17
Herein, a radical triggered fragmentary cyclization cascade reaction of ene-ynamides is presented, providing a rapid access into [1,2]-annulated indoles by an intermolecular radical addition, intramolecular cyclization, desulfonylative aryl migration, and site-selective C(sp2)-N cyclization sequence. DFT calculations support oxidation of N-centered radical species to cations prior to the C–N bond formation
直接获取 [1,2] 环化吲哚(天然产物中的关键子结构)是非常可取的,但具有挑战性。在此,提出了烯-炔酰胺的自由基引发的片段环化级联反应,通过分子间自由基加成、分子内环化、脱磺酰芳基迁移和位点选择性 C( sp 2 )-N 环化序列。DFT 计算支持在 C-N 键形成之前将 N 中心自由基物质氧化为阳离子,然后是不寻常的 aza-Nazarov 环化。