such that SO4 •-is formed at distances up to ~100 µm away from the GC electrode, thereby enabling SO4 •-to be used in an electroorganic synthetic application. Based on similar reasoning, we propose that the mediated reduction of S2O8 2-yields SO4 •-sufficiently far from the electrode to be effective in oxidizing C2O4 2-to initiate the S2O8 2-/C2O4 2-autocatalytic reaction shown in Scheme The effect of adding 10 mM C2O4 2-to the solution containing 0.5 mM Ru(NH3)6 3+ and 1.0 mM S2O8 2-is shown in Figure . Upon addition of C2O4 2-, the CV displays both a decrease in the cathodic peak current and the partial reappearance of the anodic peak (Figure , blue trace). This observation suggests that once S2O8 2-is reduced by Ru(NH3)6 2+ to form SO4 •-(eq 18), the S2O8 2- /C2O4 2-autocatalytic cycle shown in Scheme 3 is initiated, resulting in S2O8 2-being consumed by reaction with CO2 •-(eq 16) rather than through the mediated reduction by Ru(NH3)6 2+ (eq 18).