Dearomatization of Electron-Deficient Indoles with N-Alkylanilines via Visible-Light-Induced Hydroalkylation
Qiao Zhang1, Haibo Shan1, Qihang Xu1
1College of New Energy, State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, People's Republic of China.
Abstract:
Herein, a visible-light-induced, base-promoted 3 + 2 annulation was developed for the dearomatization of electron-deficient indoles with readily available N-alkylanilines, affording valuable tetrahydropyrrolo[3,4-b]indol-1(2H)-ones with high diastereoselectivity. This protocol features excellent atom economy, a broad substrate scope with exceptional functional group tolerability, and compatibility with continuous-flow conditions. Mechanistic studies suggest that photoredox catalysis generates N-α-carbon radicals, which undergo radical addition to indoles, followed by amidation, providing an efficient and scalable route to indoline derivatives.
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