Differences and Comparisons of the Properties and Reactivities of Iron(III)–hydroperoxo Complexes with Saturated Coordination Sphere

摘要: Heme and nonheme monoxygenases dioxygenases catalyze important oxygen atom transfer reactions to substrates in the body. It is now well established that cytochrome P450 enzymes react through formation of a high-valent iron(IV)–oxo heme cation radical. Its precursor catalytic cycle, iron(III)–hydroperoxo complex, was tested for activity found be sluggish oxidant hydroxylation, epoxidation sulfoxidation reactions. In recent twist events, evidence has emerged several complexes appear with via processes. Although it not clear from these studies whether reacted directly or an initial O–O bond cleavage preceded reaction. Clearly, substantially different, but origins this are still poorly understood warrant detailed analysis. work, extensive computational analysis aromatic hydroxylation by biomimetic iron systems presented, starting complex pentadentate ligand system (L52). Direct C–O investigated, as heterolytic homolytic hydroperoxo group. The calculations show [(L52)FeIII(OOH)]2+ should able initiate process, although low-energy pathway only slightly higher energy. A valence thermochemical rationalizes differences chemical reactivity main reason particular reactive comes fact they homolytically split bond, whereas breaking found.