Ferryl rebound mechanism

Ferrvl rebound mechanisms suggests that the formation of the ferryl-oxene structure is similar to those for Compound I (Por-FeIV-0) in the peroxidase reaction (Fig. 3.8). This mechanism (Groves and McClusky, 1976 Groves and Subramanian,... 

Thus, it is becoming increasingly evident that the rebound mechanism is the most probable mechanism of the hydroxylation. Nevertheless, direct proof of occurrence of the ferryl active intermediate is as yet incomplete. Above mentioned the masked radical rebound mechanism can not be excluded. 

The reaction follows the consensus mechanism for aliphatic —H activation by oxyl-ferryl compounds (35) in which the first step is H-atom abstraction via TS1 to give a hydroxo-Fe(III) complex with a C-centered alkyl radical, labeled IN. This is followed by a rebound step via TS2 to give the final product, ethanol and the ferrous active site. Overall, this is a two-electron oxidation process where the bonding orbital serves as the electron donor and the H-atom abstraction is rate limiting. 

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