Reactive intermediates in iron(III) porphyrin-catalyzed oxidation reactions

In iron(III) porphyrin-catalyzed oxidation of organic substrates by various monooxo transfer agents, oxoiron(IV) porphyrin cation radical(oxene) has been thought to be the most probable reactive intermediate. Our work, as reported here, indicates that oxo transfer to suitable substrates is possible by a distinctly different route. In case of MCPBA, the oxo transfer is very strongly solvent dependent. For example, in pure toluene solvent, intermediacy of oxene is not at all important, whereas in dichloromethane-methanol mixed solvent, the role of oxene is very significant. We also note that solvent molecules ate susceptible to self oxidation by various oxidizing systems.