Kinetic Analysis of the Formation and Decay of a Non-Heme Ferric Hydroperoxide Species Susceptible to O–O Bond Homolysis

The
formation of a ferric hydroperoxide species from [Fe­(bbpc)­(MeCN)2]2+ (bbpc = N,N′-dibenzyl-N,N′-bis­(2-pyridylmethyl)-1,2-cyclohexanediamine) and
its subsequent decomposition were analyzed kinetically. The rate of
decay is not strongly influenced by the presence of either water or
substrate, suggesting that the ferric hydroperoxide degrades through
O–O bond homolysis and is not the relevant metal-based oxidant
in the observed catalysis of C–H activation. The rate law corresponding
to the complex’s formation from O2 is consistent
with the intermediacy of a mononuclear ferric superoxo species.