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Using time resolved ESR spectroscopy and photoflash conductivity the uncatalysed, first order decay of 2-hydroxy-propyl-2-peroxyl radicals and the uncatalysed, first order generation of O2·̅and H+ were measured to have the same rate constants. The formation of O2·̅and H+was measured in H2O and D2O and a kinetic isotope effect of kH/k =D3.5 was obtained. Comparing the rate constants of the peroxyl radicals derived from methanol, ethanol and 2-propanol it was shown that the rate constant increases with increasing methyl-substitution. In 2-propanol water mixtures the rate constant of the 2-hydroxy-propyl-2-peroxyl radical increases only slightly with increasing polarity of the solvent. The experimental results are in accord with a mechanism which involves a cyclic transition state leading to a concerted elimination of HO2· followed by dissociation into H+and O2·̅.

γ-Radiolysis of N2O-saturated water or photolysis of aqueous H2O2provided a source of OH radicals. These radicals react with ethanol by preferentially abstracting an H atom at C-1. In the presence of oxygen these radicals are converted into the corresponding peroxyl radicals.

The bimolecular decay of the hydroxymethylperoxyl radical in aqueous solution (k = 2.1 x 109M-1s-1) leads mainly (80%) to one molecule of hydrogen peroxid and to two molecules of formic acid.