Distant protonated pyridine groups in water-soluble iron porphyrin electrocatalysts promote selective oxygen reduction to water.
نویسندگان
چکیده
Fe(III)-meso-tetra(pyridyl)porphyrins are electrocatalysts for the reduction of dioxygen in aqueous acidic solution. The 2-pyridyl derivatives, both the triflate and chloride salts, are more selective for the desired 4e(-) reduction than the isomeric 4-pyridyl complexes. The inward-pointing pyridinium groups influence proton delivery despite their distance from the iron centre.
منابع مشابه
ELECTROCHEMICAL INVESTIGATION OF OCTAETHYL PORPHYRIN IRON(III) CHLORIDE IN THE PRESENCE OF PYRIDINE, IMIDAZOLE AND COLLIDINE: AN APPROACH TO THE ROLE OF PYRIDINE IN THE COUPLED OXIDATION
Cyclic voltammogram and differential pulse polarograph of octaethyl porphyrin iron(III) chloride in dichloromethane was investigated in the presence of pyridine, imidazole and collidine. Values of E1/2 for FeIII/FeII redox reaction were monitored as a function of axial group concentration, and on the basis of these data, an overall oxidation-reduction and ligand addition scheme was formulated. ...
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ورودعنوان ژورنال:
- Chemical communications
دوره 48 90 شماره
صفحات -
تاریخ انتشار 2012