"Mechanistic Chemistry of Tetravalent Iron in Aqueous Solutions"

Presented by Andreja Bakac, Iowa State University

For the past several years we have focused on the generation and chemistry of aqueous Fe(IV) ions.  In strongly acidic solutions the species is Fe_aqO²⁺ as established in spectroscopic and reactivity studies, and additionally supported by DFT calculations.  Fe_aqO²⁺ is a potent oxidant that reacts with organic and inorganic substrates by both one-electron and two-electron mechanisms.  Changes in the pH, solvent, or counter ions alter the nature of Fe(IV) which has major mechanistic implications for reactions generating and/or consuming Fe(IV).  Most notably, some one-electron stoichiometric oxidations with Fe(H₂O)₆²⁺/H₂O₂ (Fenton reaction) can be transformed to two-electron catalytic oxidations by small changes in reaction conditions.