Nuclear Resonance Vibrational Spectroscopic Definition of Peroxy Intermediates in Nonheme Iron Sites.
J Am Chem Soc
; 138(43): 14294-14302, 2016 11 02.
Article
em En
| MEDLINE
| ID: mdl-27726349
ABSTRACT
FeIII-(hydro)peroxy intermediates have been isolated in two classes of mononuclear nonheme Fe enzymes that are important in bioremediation the Rieske dioxygenases and the extradiol dioxygenases. The binding mode and protonation state of the peroxide moieties in these intermediates are not well-defined, due to a lack of vibrational structural data. Nuclear resonance vibrational spectroscopy (NRVS) is an important technique for obtaining vibrational information on these and other intermediates, as it is sensitive to all normal modes with Fe displacement. Here, we present the NRVS spectra of side-on FeIII-peroxy and end-on FeIII-hydroperoxy model complexes and assign these spectra using calibrated DFT calculations. We then use DFT calculations to define and understand the changes in the NRVS spectra that arise from protonation and from opening the Fe-O-O angle. This study identifies four spectroscopic handles that will enable definition of the binding mode and protonation state of FeIII-peroxy intermediates in mononuclear nonheme Fe enzymes. These structural differences are important in determining the frontier molecular orbitals available for reactivity.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Compostos Organometálicos
/
Vibração
/
Ferro
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Estados Unidos