Oxidation of thioacetamide by ferrate(VI)

The rates of thioacetamide oxidation with ferrate(VI) (Fe(VI)) were determined as a function of pH (9.14–12.00) and temperature (15–35°C) in 0.01 M phosphate. The reaction was found to be first order for each reactant. The activation energy, ΔE≠, obtained was 59.7±0.7 kJ mol−1. The rates decrease with an increase in pH. The stoichiometry determined was 8HFeO4−+3CH3CSNH2+9H2O→8Fe(OH)3+3CH3CONH2+3SO42−+2OH−. A mechanism is proposed in which thioacetamide is oxidized by Fe(VI) in steps to sulfenyl, sulfinic, and sulfonic acid and finally to sulfate and acetamide. The comparison of results with other sulfur-containing compounds suggests that compounds undergo oxidation at S(−2) site by Fe(VI).