Although nonheme iron(III)–iodosylarene complexes present amazing oxidative efficiency and selectivity, the nature of such complexes and related oxidation mechanism are still unsolved after decades of experimental efforts. Density functional calculations were employed to explore the structure–reactivity relationship of the iron(III)–iodosylbenzene complex, [Fe^III(tpena^–) (PhIO)]²⁺ (1), in thioanisole sulfoxidation. Our theoretical work revealed that complex 1 can evolve into two resonance valence-bond electronic structures (a high-valent iron–oxo species and a monomeric PhIO species) in thioanisole sulfoxidation to present different reaction mechanisms (the novel bond-cleavage coupled electron transfer mechanism or the direct oxygen-atom transfer mechanism) as a response to different substrate attack orientations.

中文翻译：

---

非血红素铁（III）-碘亚芳基配合物的可变性导致难以捉摸的多氧化剂机制

尽管非血红素铁（III）-碘亚芳基配合物表现出惊人的氧化效率和选择性，但经过数十年的实验努力，这类配合物的性质和相关的氧化机理仍未解决。密度泛函计算用于探讨硫代苯甲醚硫氧化反应中铁（III）-碘基苯络合物[Fe ^III（tpena ^-）（PhIO ）] ²⁺（1）的结构-反应关系。我们的理论工作表明，复数1 可以在硫代苯甲醚磺化反应中演变成两个共振价键电子结构（高价铁-氧原子和单体PhIO原子），表现出不同的反应机理（新颖的键断裂耦合电子转移机理或直接的氧原子转移机制）作为对不同底物侵蚀方向的响应。