INQUIMAE   12526
INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
artículos
Título:
DFT study on the reactivity of iron porphyrins tuned by ring substitution
Autor/es:
BIKIEL, D.E., BARI, S.E., DOCTOROVICH, F., ESTRIN, D.A.
Revista:
JOURNAL OF INORGANIC BIOCHEMISTRY
Referencias:
Año: 2008 vol. 102 p. 70 - 76
ISSN:
0162-0134
Resumen:
The effect of beta-substituents (-NO2, -Br, -OCH3) in the reactivity of
Fe(II) and Fe(III) porphyrins is studied by means of density functional
theory (DFT) calculations. The binding of nitric oxide, carbon monoxide
and dioxygen (NO, CO, O2) was explored due to the relevance of their
interactions in the chemistry of heme proteins and in biomimetic
catalysis. The binding capability (BC) of the porphyrins was found to
be strongly modulated both by the donor and attractor substituents used
in the work. Unexpectedly, we found that the BC of Fe(II) porphyrins is
mainly decreased for the diatomic ligands, when both donor or
withdrawing substituents were considered. This effect was particularly
significant when the ligand was oxygen. The correlation of Fe-X and X-O
(X=N, C, O) bond distances is explained in terms of backdonation
effects.