A microelectrode study of the influence of electrolyte on the reduction of quinones in aprotic solvents

Au microdisc electrodes are used to extend previous studies of the influences of the electrolyte on the voltammetry of quinones, Q, in DMF to solutions with only a low electrolyte concentration. It is shown that the 1e- products, the semiquinones, interact with the cations of all electrolytes studied (Bu4N+, Na+, Li+ and Mg2+) and these interactions are stronger for o-quinones than p-quinones; association constants for ion pairing are reported. The voltammetry for the second 1e- reduction step is largely determined by the solubility of the product, QM2.