title: Reactivity of an FeIV-Oxo Complex with Protons and Oxidants.
abstract: High-valent Fe-OH species are often invoked as key intermediates but have only been observed in Compound II of cytochrome P450s. To further address the properties of non-heme FeIV-OH complexes, we demonstrate the reversible protonation of a synthetic FeIV-oxo species containing a tris-urea tripodal ligand. The same protonated FeIV-oxo species can be prepared via oxidation, suggesting that a putative FeV-oxo species was initially generated. Computational, Mössbauer, XAS, and NRVS studies indicate that protonation of the FeIV-oxo complex most likely occurs on the tripodal ligand, which undergoes a structural change that results in the formation of a new intramolecular H-bond with the oxido ligand that aids in stabilizing the protonated adduct. We suggest that similar protonated high-valent Fe-oxo species may occur in the active sites of proteins. This finding further argues for caution when assigning unverified high-valent Fe-OH species to mechanisms.
authors.affiliation: Department of Chemistry, University of California , Irvine, California 92697, United States.
authors.forename: Ethan A
authors.initials: EA
authors.lastname: Hill
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Weitz
authors.affiliation: Department of Chemistry, Pennsylvania State University , University Park, Pennsylvania 16802, United States.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Onderko
authors.affiliation: Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona , 17003 Girona, Spain.
authors.forename: Adrian
authors.initials: A
authors.lastname: Romero-Rivera
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Yisong
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona , 17003 Girona, Spain.|ICREA , Pg. Lluís Companys 23, 08010 Barcelona, Spain.
authors.forename: Marcel
authors.initials: M
authors.lastname: Swart
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Emile L
authors.initials: EL
authors.lastname: Bominaar
authors.affiliation: Department of Chemistry, University of California , Irvine, California 92697, United States.|Department of Chemistry, Pennsylvania State University , University Park, Pennsylvania 16802, United States.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Green
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Hendrich
authors.affiliation: Department of Chemistry, University of California , Irvine, California 92697, United States.
authors.forename: David C
authors.initials: DC
authors.lastname: Lacy
authors.affiliation: Department of Chemistry, University of California , Irvine, California 92697, United States.
authors.forename: A S
authors.initials: AS
authors.lastname: Borovik