van Dalsen Leendert, Zhang Shibo, Tian Wei, Joynson Ben W, Romano Ciro, Procter David J
Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
ACS Catal. 2025 May 5;15(10):8345-8352. doi: 10.1021/acscatal.5c02029. eCollection 2025 May 16.
α-Amido sulfonium salts are bench-stable precursors of α-amidyl radicals, prepared directly from tertiary amides. These largely unexplored sulfonium salts engage in metal-free photocatalytic C(sp)-C(sp) and C(sp)-C(sp) bond formation in cross-coupling reactions that realize the formal α-alkylation, α-alkenylation, and α-arylation of amides. Fine-tuning the photocatalytic conditions allows divergent access to important 1,4-dicarbonyl compounds, skipped unsaturated amides, and α-heteroarylated amides, thus showcasing the role of α-amido sulfonium salts in establishing a novel platform for amide functionalization. Preliminary mechanistic experiments support a photocatalytic cycle in which the sulfonium salts are reduced to form α-amidyl radicals that couple with various electron-rich partners in a chemodivergent approach for the introduction of complexity in amides.
α-酰胺基锍盐是α-酰胺基自由基的稳定前体，可直接由叔酰胺制备。这些尚未得到充分研究的锍盐在交叉偶联反应中参与无金属光催化C(sp)-C(sp)和C(sp)-C(sp)键的形成，实现酰胺的形式上的α-烷基化、α-烯基化和α-芳基化。微调光催化条件可不同地获得重要的1,4-二羰基化合物、跳跃式不饱和酰胺和α-杂芳基化酰胺，从而展示了α-酰胺基锍盐在建立酰胺功能化新平台中的作用。初步机理实验支持一个光催化循环，其中锍盐被还原形成α-酰胺基自由基，这些自由基以化学发散的方式与各种富电子伙伴偶联，从而在酰胺中引入复杂性。
