Preparation and characterization of manganese(IV) in aqueous acetic acid

Article abstract of DOI:10.1039/c0dt00476f

Mn(iv) acetate was generated in acetic acid solutions and characterized by UV-vis spectroscopy, magnetic susceptibility, and chemical reactivity. All of the data are consistent with a mononuclear manganese(iv) species. Oxidation of several substrates was studied in glacial acetic acid (HOAc) and in 95 : 5 HOAc-H₂O. The reaction with excess Mn(OAc)₂ produces Mn(OAc)₃ quantitatively with mixed second-order kinetics, k (25.0 °C) = 110 ± 4 M^-1 s^-1 in glacial acetic acid, and 149 ± 3 M^-1 s^-1 in 95% AcOH, ΔH ^? = 55.0 ± 1.2 kJ mol^-1, ΔS ^? = -18.9 ± 4.1 J mol^-1 K^-1. Sodium bromide is oxidized to bromine with mixed second order kinetics in glacial acetic acid, k = 220 ± 3 M^-1 s^-1 at 25 °C. In 95% HOAc, saturation kinetics were observed. The Royal Society of Chemistry 2010.