Active sites and mechanisms of bioinspired oxidation with H2O2, catalyzed by non-heme Fe and related Mn complexes

•The state-of-the-art mechanistic landscape of biomimetic and bioinspired oxidations is presented.•Structurally and functionally similar Fe and Mn intermediates are discussed and compared.•With particular focus on the nature of active species in the oxidation of CC and CH groups with H2O2.•Most prominent catalysts are considered briefly from a synthetic perspective.

In the last two decades, considerable efforts were invested in the search for synthetic iron and manganese catalysts with nonporphyrinic ligands, mimicking metalloenzymes in the oxygenation at CH and CC bonds of organic molecules. In many cases, the detailed knowledge of intimate reaction mechanisms and of the nature of active sites was critical for the rational design of biomimetic catalysts with predictable reactivities. This review discusses the up-to-date mechanistic landscape of non-heme iron and manganese catalyzed oxidations of olefinic groups and aliphatic CH groups with H2O2.