High-valent metal-oxo complexes play central roles as active oxygen atom transfer (OAT) agents in many enzymatic and synthetic oxidation catalysis. This review focuses on our recent advances in application of photochemical approaches to probe the oxidizing metal-oxo species with different metals and macrocyclic ligands. Under visible light irradiation, a variety of important metal-oxo species including iron-oxo porphyrins, manganese-oxo porphyrin/corroles, ruthenium-oxo porphyrins, and chromium-oxo salens have been successfully generated. Kinetical studies in real time have provided mechanistic insights as to the reactivity and reaction pathways of the metal-oxo intermediates in their oxidation reactions. In photo-induced ligand cleavage reactions, metals in n⁺ oxidation state with the oxygen-containing ligands bromate, chlorate, or nitrites were photolyzed. Homolytic cleavage of the O-X bond in the ligand gives (n + 1)⁺ oxidation state metal-oxo species, and heterolytic cleavage gives (n + 2)⁺ oxidation state metal-oxo species. In photo-disproportionation reactions, reactive Mⁿ⁺¹-oxo species can be formed by photolysis of μ-oxo dimeric Mⁿ⁺ complexes with the concomitant formation of M^n-1 products. Importantly, the oxidation of M^n-1 products by molecular oxygen (O₂) to regenerate the μ-oxo dimeric Mⁿ⁺ complexes in photo-disproportionation reactions represents an attractive and green catalytic cycle for the development of photocatalytic aerobic oxidations.

高价金属氧配合物在许多酶促和合成氧化催化中作为活性氧原子转移 (OAT) 剂发挥核心作用。本综述重点介绍了我们在应用光化学方法来探测具有不同金属和大环配体的氧化金属氧物种方面的最新进展。在可见光照射下，已成功生成了多种重要的金属氧化合物，包括铁氧卟啉、锰氧卟啉/corroles、钌氧卟啉和铬氧合盐。实时动力学研究提供了关于金属-氧代中间体在其氧化反应中的反应性和反应途径的机理见解。在光诱导配体裂解反应中，n ^{+ 中的}金属含氧配体溴酸盐、氯酸盐或亚硝酸盐的氧化态被光解。配体中 OX 键的均裂产生 ( n  + 1) ⁺氧化态金属-氧类物质，而异裂产生 ( n  + 2) ⁺氧化态金属-氧类物质。在光歧化反应中，可以通过 μ-氧代二聚体 M ⁿ⁺复合物的光解形成反应性 M ⁿ⁺¹ -氧代物质，同时形成 M ^n-1产物。重要的是，M ^n-1产物被分子氧 (O ₂ )氧化以再生 μ-氧代二聚体 M ⁿ⁺ 光歧化反应中的复合物代表了光催化有氧氧化发展的有吸引力的绿色催化循环。