Recent Advances in Paired Electrosynthesis

Abstract

Progress in electroorganic synthesis is linked to innovation of new synthetic reactions with impact on medicinal chemistry and drug discovery and to the desire to minimise waste and to provide energy‐efficient chemical transformations for future industrial processes. Paired electrosynthetic processes that combine the use of both anode and cathode (convergent or divergent) with minimal (or without) intentionally added electrolyte or need for additional reagents are of growing interest. In this overview, recent progress in developing paired electrolytic reactions is surveyed. The discussion focuses on electrosynthesis technology with proven synthetic value for the preparation of small molecules. Reactor types are contrasted and the concept of translating light‐energy driven photoredox reactions into paired electrolytic reactions is highlighted as a newly emerging trend.

Catalysis for e-Chemistry: Need and Gaps for a Future De-Fossilized Chemical Production, with Focus on the Role of Complex (Direct) Syntheses by Electrocatalysis

“… 130 , 131 Exploring more systematically the many possible new paths, offering also process intensification, given by tandem and/or paired electrocatalytic reactions. 132 , 133 We have cited the examples of direct (one-step) glucose conversion to adipic acid, or the production of the monomers for PEF polymer synthesis on both sides of the electrocatalytic cell, a greener polymer substituting PET (polyethylene terephthalate), one of the largest in market volume polymers in current use. Intensifying research on the direct synthesis of ethylene or methanol/ethanol by electrocatalytic reduction of CO 2 , which were not discussed here having been already discussed in many reviews, for example by Zhao et al 2 and Ra et al 16 Ethylene or methanol/ethanol can be then used as such or as a building block for further e -chemistry.…”

“…Direct electrocatalytic amination (formation of C–N bonds) is an interesting possibility which can exploit also nitrogen sources as nitrate, also produced, for example, by plasma-catalysis from air Exploiting the new possibilities offered by the electrocatalytic conversion of biomethane, which has been at large unexplored up to now. , Exploring more systematically the many possible new paths, offering also process intensification, given by tandem and/or paired electrocatalytic reactions. , We have cited the examples of direct (one-step) glucose conversion to adipic acid, or the production of the monomers for PEF polymer synthesis on both sides of the electrocatalytic cell, a greener polymer substituting PET (polyethylene terephthalate), one of the largest in market volume polymers in current use. Intensifying research on the direct synthesis of ethylene or methanol/ethanol by electrocatalytic reduction of CO 2 , which were not discussed here having been already discussed in many reviews, for example by Zhao et al and Ra et al Ethylene or methanol/ethanol can be then used as such or as a building block for further e -chemistry. A large part of the research in these areas is focused on developing electrocatalysts with improved performances (especially Faradaic efficiency), and to identify the mechanistic features responsible for this improvement.…”

“…Exploring more systematically the many possible new paths, offering also process intensification, given by tandem and/or paired electrocatalytic reactions. , We have cited the examples of direct (one-step) glucose conversion to adipic acid, or the production of the monomers for PEF polymer synthesis on both sides of the electrocatalytic cell, a greener polymer substituting PET (polyethylene terephthalate), one of the largest in market volume polymers in current use.…”

Versatile Tools for Understanding Electrosynthetic Mechanisms

“…Aptly described by Hilt as the “holy grail of organic electrolysis”, paired electrolysis is an exceptionally powerful electrosynthetic technique that maximizes the energy efficiency of the cell through reactions that occur at both the anode and the cathode. ,, Yan et al and Hilt et al provides in-depth descriptions of five common types of paired electrolysis methods as well as detailed examples of reactions carried out under each method. Likewise, Moeller and co-workers illustrate many organic transformations that can be carried out via paired electrosynthesis. − As shown in Figure , parallel paired electrolysis involves oxidation and reduction of two different substrates that occur simultaneously to afford two different products.…”

Emerging Graphene Derivatives and Analogues for Efficient Energy Electrocatalysis

“…[ 14–18 ] With the deepening of electrocatalysis research in recent years, new types of electrocatalytic reactions involving more complex bond cleavage and formation are coming into focus. [ 11,12,19–21 ] For example, the electrosynthesis of N‐containing organics (e.g., urea, amides, amines, nitriles) usually contains the coupling of *CO or *CH x with *NH y to form chemical bonds between C and N. This requires the activation of both C‐containing (e.g., CO 2 , CO, CH 4 ) and N‐containing (e.g., NO x , NO 2 − /NO 3 − , N 2 , NH 3 ) reactants on the electrocatalyst. [ 11,19 ] To deal with reactions with increasing complexity and further boost the activity for commonly investigated electrocatalytic reactions, new concerns on the design of electrocatalysts have been raised to regulate the adsorption energy and configurations effectively and independently, for example, the introduction of multiple active sites and the design of surface nanoconfinement or functional modification.…”