Oxygen transfer involving nonheme iron: the influence of leaving group ability on the rate constant for oxygen transfer to (EDTA)Fe(III) from peroxycarboxylic acids and hydroperoxides.

Ethylenediaminetetraacetato iron(III) [(EDTA)Fe(III)] has been shown to react with a series of four peroxycarboxylic acids and four alkyl hydroperoxides (YOOH; dry methanol solvent, 30 degrees C) by heterolytic O-O bond scission that accompanies the transfer of an oxygen atom to the iron(III) moiety [(EDTA)Fe(III) + YOOH----[(EDTA)(FeO)]+ + YOH]. A single linear free-energy relationship exists for both peroxycarboxylic acids and alkyl hydroperoxides when the logarithm of the second-order rate constant (kYOOH) for reaction of YOOH species with (EDTA)Fe(III) is plotted vs. the pKa of the YOH leaving group.