Oxygen donors iodosobenzene

Such reaction with aromatic hydroperoxides has been studied by Coon and coworkers [54], Instead of hydroperoxides, iodosobenzenes, and iodobezene acetates may participate in Reaction (8) as the oxygen donors [55]. These authors proposed that the reaction of cytochrome P-450 with iodosobenzene proceeds to form an iron-oxo intermediate complex containing only one oxygen atom derived from the substrate. 

Summarizing the information disclosed in the section above, one notes that polyoxometalates appear to be versatile oxidation catalysts capable of activating various mono-oxygen donors such as iodosobenzene, periodate, ozone, nitrous oxide, and sulfoxides. Some of these reactions are completely new from both a synthetic and mechanistic point of view. The various reaction pathways expressed are also rather unusual and point to the many options and reaction pathways available for oxidation catalyzed by polyoxometalates. 

Although the exact sequence of intermediates seen in the P-450 reaction cycle is not observed with chloroperoxidase, one feature of the chloroperoxidase reaction cycle (Fig. 4) does occur for the P-450 system (Fig. 3). Addition of oxygen atom donors such as peroxides or iodosobenzene to P-450 state 2 (the enzyme-substrate complex) results in the formation of product, in a reaction that probably has state 7 as an intermediate. The first step of this alternative, short-circuit cycle, also called the peroxide shunt, is essentially identical to the first step of the chloroperoxidase catalytic pathway. 

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