REACTIONS OF HYDROXYALKYL RADICALS WITH NICKEL(II) AND COPPER(II) COMPLEXES OF 2-METHYL-5-NITRO-1H-IMIDAXOLE-1-ETHANOL - A STEADY-STATE GAMMA-RADIOLYSIS AND FLASH-PHOTOLYSIS STUDY

The yields for the loss of chromophore of Ni(II) and Cu(II) complexes of metronidazole, G(-Ni(II)M) and G(-CU(II)M), reached almost zero whe n their aqueous solutions were gamma-irradiated in the presence of 0.4 mol . dm(-3) of MeOH, EtOH, i-PrOH and t-BuOH in aerated medium. Howe ver, under N2O saturated conditions, these yields attained limiting va lues which suggests that the hydroxyalkyl radicals, derived from the a lcohols by reaction with OH, react with the complexes in deaerated med ium. But in aerated medium they react preferentially with O-2. The rat e constants for the reactions of the different hydroxyalkyl radicals w ith the complexes have been determined by the flash photolysis techniq ue and the plausible mechanisms for the reactions have been suggested.