A study was made on the kinetics and mechanism of the reaction 2Mn042-+ Product 2Mn04-+ S in aqueous solutions of 0.10 to 2.0 mol dm-3 alkaline concentrations. The substrates (S) applied were ethane-l,a-diol (ethylene glycol), glycol aldehyde, glycollic acid, and glyoxylic acid. Glycol aldehyde and glyoxylic acid were present in the form of dihydrate. In each case alkoxy anion is the reactive form and the Kg constant of deprotonation can be calculated from the kinetic data.A mechanism based on electron abstraction is suggested. Manganate reacts with these substrates much slower than permanganate.

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The kinetics and mechanism of the oxidation of ketones with permanganate ions were studied in aqueous acidic and alkaline media for acetone, hydroxyacetone, butan-2-one and butane-2,3-dione. Acid catalysed nucleophilic addition of the permanganate to the carbonyl C-atom is suggested. In alkaline media, parallel with electron abstraction from the enolate, a concerted mechanism is proposed. Intermediates and end products were determined. Comparisons between halogenation and oxidation have been made.

The kinetics and mechanism of permanganate ion oxidation of acetylacetone (Acac) was studied in acidic and alkaline media. The rate constants for keto, enol, and enolate anions were determined and discussed. Delocalization of the π-electrons of the double bond by conjugation results in a slower oxidation rate of enol than can be usually observed for unsaturated compounds. In the case of the keto form, the acid-catalyzed nucleophilic attack of permanganate ion occurs on the carbonyl-C atom. For enolate anion a mechanism with basis-catalyzed electron abstraction is suggested.