Calculated and observed oxidising capacities of manganese oxides in the oxidation of cinnamyl alcohol in neutral solution

Abstract

A mechanism for the oxidation of cinnamyl alcohol in neutral solution by manganese oxides based on the adsorption of the alcohol molecule on to metal ions in the oxide surface by δ-, π-, or σ-bonding is proposed. The orientation of the adsorbed alcohol molecule may be such that oxidation of the carbinol group can be accomplished by transfer of electrons and protons to nearby manganese and oxide ions, respectively. The theoretical oxidising capacities of Mn₃O₄, α-Mn₂O₃, and β-MnO₂ calculated from the number of suitable metal and oxide ions found in the various crystal faces of each oxide are in reasonable agreement with experimental results.