Paired Electrochemical Reactions and the On‐Site Generation of a Chemical Reagent

Abstract

While the majority of reported paired electrochemical reactions involve carefully matched cathodic and anodic reactions, the precise matching of half reactions in an electrolysis cell is not generally necessary. During a constant current electrolysis almost any oxidation and reduction reaction can be paired, and in the presented work we capitalize on this observation by examining the coupling of anodic oxidation reactions with the production of hydrogen gas for use as a reagent in remote, Pd‐catalyzed hydrogenation and hydrogenolysis reactions. To this end, an alcohol oxidation, an oxidative condensation, intramolecular anodic olefin coupling reactions, an amide oxidation, and a mediated oxidation were all shown to be compatible with the generation and use of hydrogen gas at the cathode. This pairing of an electrolysis reaction with the production of a chemical reagent or substrate has the potential to greatly expand the use of more energy efficient paired electrochemical reactions.

C−H Oxygenation Reactions Enabled by Dual Catalysis with Electrogenerated Hypervalent Iodine Species and Ruthenium Complexes

“…Lastly, the regeneration of the active catalyst takes place. The formation of molecular hydrogen as the only stoichiometric by‐product was confirmed by GC headspace analysis, and bears great potential for paired electrochemical approaches …”

“…Communications of molecular hydrogen as the only stoichiometric by-product was confirmed by GC headspace analysis, [12] and bears great potential for paired electrochemical approaches. [19] In conclusion, we have devised an ovel electrochemical co-catalytic system for the CÀHo xygenation of synthetically useful amides and ketones by challenging weak O-coordination. Theversatile iodine(III)/ruthenium(II)-electrocatalyzed CÀHf unctionalization was enabled by orchestrating the catalytic generation of hypervalent iodine(III) reagents with sustainable electricity as ac ost-effective terminal oxidant, with the formation of molecular hydrogen as the sole byproduct.…”

The preparation and applications of amides using electrosynthesis

“…49 This sort of reaction has also been reported when using carbamate substrates. 51,52 In 2016, an example of Shono-type oxidation being used to bond γ-lactams 58 and anilines together was reported by Gong and Huang, 53 who used mild and sustainable conditions (i.e. room temperature and no metal catalyst) to produce a range of coupled products in an undivided cell (Scheme 34).…”

Photoelectrochemical Cells for Artificial Photosynthesis: Alternatives to Water Oxidation

“…High regio‐ and trans‐selectivity were observed owing to the stability of the benzyl radical that formed. Besides being used as a solar fuel, the H 2 generated at the cathode can also be directly transferred and employed in hydrogenation and hydrogenolysis reactions (Figure e) by cannulating the headspace gases from the cathodic chamber to another reaction mixture …”