Chiappini Nicholas D, Geunes Eric P, Bodak Ethan T, Knowles Robert R
Department of Chemistry, Princeton University, Princeton NJ, 08544.
ACS Catal. 2024 Feb 16;14(4):2664-2670. doi: 10.1021/acscatal.3c05598. Epub 2024 Feb 6.
A light-driven method for the generation of aryl radicals from triarylbismuth(III) and (V) reagents is described. Aryl radical generation is proposed to occur through ligand-assisted mesolytic cleavage of an organobismuth(IV) intermediate generated from either oxidation of Bi or reduction of Bi. This mode of aryl radical generation is demonstrated to be compatible with a range of bimolecular radical arylations, including hydroarylation of electron-deficient olefins and arylation of diboronates, disulfides, sulfonyl cyanides, phosphites and isocyanides. The intermediacy of an aryl radical is supported by radical trapping and radical clock experiments, and Bi-aryl mesolysis is supported computationally.
本文描述了一种由三芳基铋（III）和（V）试剂光驱动生成芳基自由基的方法。芳基自由基的生成被认为是通过配体辅助的均裂裂解，该裂解发生在由铋的氧化或铋的还原生成的有机铋（IV）中间体上。这种芳基自由基的生成模式被证明与一系列双分子自由基芳基化反应兼容，包括缺电子烯烃的氢芳基化反应以及二硼酸酯、二硫化物、磺酰氰、亚磷酸酯和异腈的芳基化反应。自由基捕获和自由基钟实验支持了芳基自由基的中间体性质，并且通过计算支持了Bi-芳基均裂反应。
