A Unified Approach to Lactonization/Lactamization by Leveraging Tether-Tunable Distonic Radical Anions

We report using visible-light-induced in situ generation of tether-tunable distonic radical anions for the general catalytic lactonization/lactamization of aromatic carboxylic acids and benzamides. Its success relies on the specific cyclic diacyl peroxide and catalytic amount of CsI, enabling the generation of electrophilic heteroatom-centered radicals via a philicity regulation strategy. Key features include operational simplicity, excellent functional group tolerance, broad substrate scope, high chemo- and regioselectivity, gram-scale scalability, and application to synthesis of urolithin derivatives and 3-n-butylphthalide.