Pulse radiolysis of mono- and binuclear copper(II) macrocyclic complexes
摘要:
Pulse radiolytic reduction of a series of nitro-substituted tetraaza copper(II) complexes with the aquated electron (e(aq)) results in formation of nitro radical anions. By contrast, reaction of pendent nitro dithia-diaza copper(II) analogues with e(aq) achieves exclusive reduction of the metal centre. Oxidation of all tetraaza copper(II) complexes with the hydroxyl radical (OH) resulted in formation of stable copper(III) complexes, whereas no metal-centred oxidation was observed for the corresponding Cu(II)N2S2 complexes. The variation in reactivity, effectively evidence for selectivity in reduction with e(aq) or oxidation with OH, was attributed to the shift in the Cu(II/I) half-wave potentials going from a tetraaza to a dithia-diaza donor set.