Robust iron coordination complexes with N-based neutral ligands as efficient fenton-like catalysts at neutral pH
Texto Completo
RobustIronCoordination.pdf
Solicita copia
Al rellenar este formulario estáis solicitando una copia del artículo, depositado en el repositorio institucional (DUGiDocs), a su autor o al autor principal del artículo. Será el mismo autor quien decidirá enviar una copia del documento a quien lo solicite si lo considera oportuno. En todo caso, la Biblioteca de la UdG no interviene en este proceso ya que no está autorizada a facilitar artículos cuando éstos son de acceso restringido.
Compartir
The homogeneous Fenton-like oxidation of organic substrates in water with hydrogen peroxide, catalyzed by six different metal coordination complexes with N-based neutral ligands, was studied at ambient conditions and initial pH 7, employing hydrogen peroxide as the terminal oxidant. At low catalyst concentration, the catalytic oxidative depletion of toluene achieved by selected catalysts was much more efficient than that obtained by the Fenton reagent at pH 3. The influence of pH, the water matrix and the catalyst/hydrogen peroxide concentration were investigated for the oxidation of toluene employing [FeCl2(bpmcn)] (1, bpmcn = N,N′-bis(2-pyridylmethyl)-N, N′-dimethyl-trans-1,2-diaminocyclohexane), the most efficient catalyst of the series. Moreover, the evolution of catalysts [FeCl2(bpmcn)] (1) and [Fe(OTf)2(Pytacn)] (3, Pytacn = 1-(2-pyridylmethyl)-4,7-dimethyl- 1,4,7-triazacyclononane, OTf = trifluoromethanesulfonate anion) during the course of the reaction was also studied by electrospray ionization mass spectrometry (ESI-MS). The oxidation products derived from toluene oxidation were also analyzed. A plausible mechanism of toluene degradation using [FeCl2(bpmcn)] (1) and [Fe(OTf)2(Pytacn)] (3) as catalysts was proposed, which involves the coexistence of a metal-based path, analogous to that operating in organic media where substrate oxidation is executed by an iron(V)-oxo-hydroxo species, in parallel to a Fenton-type process where hydroxyl radicals are formed
Tots els drets reservats