Substrate and co-catalyst effects on the local coordination environment of a Fe-porphyrin catalyst
(EN)
Christoforidis, K. C.
(EN)
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας
(EL)
Christoforidis, K. C.
(EN)
The effect of imidazole and pentachlorophenol (PCP) on coordination and redox properties of a Fe-porphyrin catalyst were studied by EPR and UV-Vis spectroscopy. In the EPR spectra three different Fe-porphyrin species were resolved, corresponding to (a) FeR(4)P-Cl (S = 5/2, g(x) = 6.13, g(y) = 5.77, g(z) = 1.99), (b) FeR(4)P-[Imidazole](1) (S = 5/2, g(x) = 6.80, g(y) = 5.20, g(z) = 1.99), and (c) FeR(4)P-[Imidazole](2) (S = 1/2, g(1) = 2.85, g(2) = 2.30, g(3) = 1.56). The stability constants logK for FeR(4)P-[Imidazole](1) and FeR(4)P-[Imidazole](2) have been estimated. PCP affects the redox potential of the Fe-porphyrin species. The system FeR(4)P/Imid/NaIO(4)/PCP behaves as an integral entity with redox potential appropriate for efficient redox cycling of the iron. (C) 2010 Elsevier B. V. All rights reserved.
(EN)
