The putative Co IV species generated at the electrode could be intercepted either before or after diffusing into the bulk solution. An electrolyte effect could be used to probe this step. Moeller has shown that for a radical cation mediated reaction carried out in methanol, the effective methanol concentration near the anode could be lowered by an electrolyte that forms a more hydrophobic electric double layer (EDL). Indeed, we noticed that for the hydromethoxylation reaction shown in Figure , the selectivity for methanol trapping over isomerization was substantially lower with the more hydrophobic NBu4BF4 than with LiClO4. Therefore, it seems that the Co IV species is mostly trapped near the electrode rather than in the bulk solution, which is consistent with the irreversible oxidation wave assigned to Co III/IV in Figure .