Reactions of hydroperoxides with iron(III) prophyrins: Heterolytic cleavage followed by hydroperoxide oxidation

Reaction of α,α-dimethylphenethyl hydroperoxide with iron(III) tetramesitylporphyrin in protic solvent gives alkoxy- radical products and little epoxide. Such observations are usually interpreted as evidence for homolysis of the O-O bond in the catalytic process. Yet the same products are now obtained under similar conditions from the reaction of this hydroperoxide with the high-valent oxene (Fe⁺=O), generated unambiguously. Therefore such products are not necessarily evidence for homolysis but are consistent with heterolysis. Nevertheless, the solvent can affect the nature of O-O cleavage.