کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1317009 | 976499 | 2008 | 7 صفحه PDF | دانلود رایگان |
The effect of β-substituents (–NO2, –Br, –OCH3) in the reactivity of Fe(II) and Fe(III) porphyrins is studied by means of density funcional 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.
Journal: Journal of Inorganic Biochemistry - Volume 102, Issue 1, January 2008, Pages 70–76