November 8, 2016

Paired Electrolysis in the Simultaneous Production of Synthetic Intermediates and Substrates

In electrochem. processes, an oxidn. half-reaction is always paired with a redn. half-reaction.  Although systems for reactions such as the redn. of CO2 can be coupled to H2O oxidn. to produce O2 at the anode, large-scale O2 prodn. is of limited value.  One may replace a low-value half-reaction with a compatible half-reaction that can produce a valuable chem. compd. and operate at a lower potential.  In doing so, both the anodic and cathodic half-reactions yield desirable products with a decreased energy demand.  Here the authors demonstrate a paired electrolysis in the case of the oxidative condensation of syringaldehyde and o-phenylenediamine to give 2-(3,5-dimethoxy-4-hydroxyphenyl)benzimidazole coupled with the redn. of CO2 to CO mediated by mol. electrocatalysts.  The authors also present general principles for evaluating current-voltage characteristics and power demands in paired electrolyzers.

By: Llorente, Mark J.; Nguyen, Bichlien H.; Kubiak, Clifford P.; Moeller, Kevin D.

J. Am. Chem. Soc., 2016, 138 (46), pp 15110–15113
Publication Date (Web): November 8, 2016