Studies of Nitrite Reduction to Nitric Oxide by Vanadium and Iron Thiolate Complexes

Abstract

In this work we reported the nitrite reduction by vanadium and iron complexes supported by a tris(benzenethiolato)phosphine (PS3”) derivative Vanadium (III) complex [PPh4][V(PS3”)(Cl)] (3) was served as the starting material to react with nitrite due to the labile nature of bound chloride The formation of [PPh4][V(PS3”)(NO)] (1) was characterized by UV-vis-NIR FT-IR NMR ESI-MS spectra A vanadium (IV)-oxo complex was proposed as the second product that was evidenced by ESI-MS and EPR spectra According to the spectroscopic observations a reaction pathway was proposed via a dinucler vanadium intermediate bridging by a nitrite (μ2-(η1-N η1-O)-NO2) Moreover the reaction with nitric oxide was also investigated by UV-vis-NIR spectra In addition the formation of iron nitrosyl complex [PPh4][Fe(PS3”)(NO)] (2) by the reactions of [PPh4][Fe(PS3”)(CH3CN)] (4) [PPh4][Fe(PS3”)(OCH3)] (5) and [PPh4][Fe(PS3”)(Cl)] (6) with nitrite were also studied by UV-vis-NIR and ESI-MS spectra It was found that an extra equivalents of nitrite is needed to form [Fe(PS3”)(NO)]- An iron-oxo species was observed from the reaction mixture by ESI-MS spectra Accordingly the nitrite reduction iron and vanadium complexes in this system might share similar pathways Finally overall comparison for iron and vanadium nitrosyl complexes is summarized here The structural parameters and NO vibration frequency are particularly emphasized here

Date of Award	2017 Jan 23
Original language	English
Supervisor	Hua-Fen Hsu (Supervisor)