O2 reductive activation using molecular Fe and Mn complexes: Reaction intermediates and reactivity

Mimicking bio-inspired chemistry to achieve a variety of organic reactions involving oxidations or oxygen atom insertions continues to be a compelling challenge for chemists. Indeed, oxidation reactions represent a major fraction of industrial chemical processes but typically demand harsh conditions. Thus numerous research groups have attempted to reproduce metalloenzymes reactivity and in particular the manner in which the metal active site activates O 2 to obtain highly efficient and selective transformations. Various oxidizing intermediates, M-superoxo [M(OO • )], M-peroxo [M(OO − )], M-hydroperoxo [M(OOH)] or the high valent M-oxo [M(O)] have been proposed as key intermediates for biomimetic oxidation reactions. Although synthetic analogues of these intermediates have been successfully isolated, they were generally generated using hazardous chemical oxidants. In this review, we provide an overview on synthetic heme and non-heme iron and manganese oxidizing intermediates generated directly from O 2 as oxygen source for the purpose of oxidizing small organic molecules, covering the decade 2015–2025.