Ce^IV - and HClO₄ -Promoted Assembly of an Fe₂^IV (μ-O)₂ Diamond Core from its Monomeric Fe^IV =O Precursor at Room Temperature

Diiron(IV)-oxo species are proposed to effect the cleavage of strong C-H bonds by nonheme diiron enzymes such as soluble methane monooxygenase (sMMO) and fatty acid desaturases. However, synthetic mimics of such diiron(IV) oxidants are rare. Herein we report the reaction of (TPA*)Fe^II (1) (TPA*=tris(3,5-dimethyl-4-methoxypyridyl-2-methyl)amine) in CH₃ CN with 4 equiv CAN and 200 equiv HClO₄ at 20 °C to form a complex with an [Fe^IV₂ (μ-O)₂ ]⁴⁺ core. CAN and HClO₄ play essential roles in this unprecedented transformation, in which the comproportionation of Fe^III -O-Ce^IV and Fe^IV =O/Ce⁴⁺ species is proposed to be involved in the assembly of the [Fe^IV₂ (μ-O)₂ ]⁴⁺ core.