Model for the Cofactor Formation Reaction of E. Coli Ribonucleotide Reductase. From a Diiron(II) Precursor to an FeIIIFeIV Species via a Peroxo Intermediate

The diiron(II) complex [Fe2(μ-OH)2(6-Me3−TPA)2](ClO4)2 has recently been synthesized as a model of nonheme diiron proteins. This compound reacts with dioxygen at low temperatures to generate a diiron(III) peroxo species followed by a high-valent Fe(III)Fe(IV) complex.