Indeed, the photoactive species was proved not to be the diarylcarbenium salt itself, but two intermediates, a stable S–C adduct and an ion couple, that were formed after its interaction with sodium benzenesulfinate. Upon absorbing light, the ion couple could reach an excited state with a charge-transfer character which gave the fundamental sulfonyl radical. A PCET (proton-coupled electron transfer) closes
在本文中,我们展示了二芳基甲基四
氟硼酸盐作为可见光促进未活化烯烃氢磺酰化催化剂的合成潜力。这些稳定且易于在多克规模上制备的盐首次被用作有机催化剂。有趣的是,仅 1 mol% 的催化剂负载量就可以从良好到极好的收率有效地获得砜产品,具有高官能团耐受性和高达 15 mmol 烯烃的可扩展性。此处介绍的实验和计算机理研究揭示了形成关键磺酰基的另一种机制。事实上,光活性物种被证明不是二芳基碳鎓盐本身,而是两个中间体,一个稳定的 S-C 加合物和一个离子对,与
苯亚磺酸钠相互作用后形成。吸收光后,离子对可以达到具有电荷转移特性的激发态,从而产生基本的磺酰基。PCET(质子耦合电子转移)关闭重整二芳基碳鎓盐的催化循环。