Oxidation of transition metal complexes by hydroxyl radicals

OXIDATION OF TRANSITION METAL COMPLEXES BY HYDROXYL RADICALS 

Oxidation of transition metal complexes by hydroxyl radicals can proceed by different mechanisms (a) by the inner-sphere mechanism in which a ligand of the metal complex is replaced by the hydroxyl radical, the replacement being followed by electron transfer (b) by the outer-sphere mechanism (c) by abstraction of the hydrogen atom of OH, or in some other way. 

The inner-sphere electron transfer mechanism (a) by the OH radical is represented by expressions (6.3.1) and (6.3.2)  

The reaction rate can be determined by either of these two reactions. In many cases, the dissociation of the coordinated water (6.3.1) is the slowest and thus the rate-determining step. 

Oxidation of Ti by the hydroxyl radical takes place by the inner-sphere mechanism.  

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