Interes ngly, no further increase in rate was observed when the cell poten al was set to > 6.0 V. This can be a ributed to a mass transport limita on; as the reac on rate is completely controlled by the ability to increase convec on in the solu on (1000 rpm is the maximum overhead s r rate), and no further increase in the thermodynamic driving force for the electron transfer will increase the reac on rate. This effect can be observed by comparing the rates of a reac on run at constant poten al while varying the s r rate in the reactor (Figure ). Using the reac on condi ons op mized on small scale and running the reac on at 6.0 V cell poten al with 1000 rpm s r rate, a significant amount of both overoxida on and an elimina on product were observed (Figure ). The overoxida on product, 3, reached close to 10% of the reac on products by the end of the reac on, and mostly occurred at high conversion. The elimina on product, 4, was present throughout and reached a maximum of around 10%. As expected, once the reac on had reached full conversion of 1, the forma on of 3 becomes much more rapid. Running the reac on at a slightly lower temperature (15°C) had a drama c effect on the reac on profile, completely suppressing the forma on of 4 and minimizing the forma on of 3 to below 5%. However, overoxida on s ll occurred rapidly once full conversion of 1 had been achieved at 6.0 V applied poten al. As demonstrated in Figure decreasing reac on temperature also leads to a slight decrease in rate. This stems from the decreasing conduc vity of the solu on as viscosity increases, which reduces ion mobility. Overall, maximizing conduc vity without sacrificing selec vity, should be considered a key parameter for developing an electrochemical reac on in flow. Addi onally, it was observed on gram scale that TEA-BF4 was prone to crystalizing from solu on at 15°C; therefore, effect of electrolyte iden ty was explored further. U lizing the more soluble tetrabutylammonium tetrafluoroborate (TBA-BF4) the reac on rate was significantly slower. This can be ra onalized by looking at the rela ve conductances of tetraalkylammonium ions, which tend to be less conduc ve as the length of the alkyl chain increases, consistent with their rela ve Stokes radii. 69,70 Using a 1:1 combina on of TEA-BF4 and TBA-BF4 provided an acceptable compromise between solubility and conduc vity resul ng in an 1.5X increase in rate rela ve to the use of TBA-BF4 alone. (Figure ). Comparing the rela ve rates of oxida on of 1 and 2 revealed that at +2.6 V working electrode poten al (6.0 V cell poten al), the rate of oxida on of 1 is approximately 3.5x faster than oxida on of the Shono product 2. As expected by examining the CVs of each compound showed that decreasing the working electrode poten al to the thermodynamic poten al for oxida on of 2 (+1.8 V vs Ag/AgNO3, 4.4 V cell poten al), leads to a larger difference in the rela ve rates of oxida on of 1 and 2, with 1 reac ng approximately 7.5x faster than 2. This difference in rela ve rates would allow for much more selec ve forma on of the mono-oxida on product, although it would also decrease the overall throughput per unit me by 66% (see Suppor ng Informa on. for details).