The critical aspects of the corrosion of metal electrodes in cathodic reductions are covered. We discuss the involved mechanisms including alloying with alkali metals, cathodic etching in aqueous and aprotic media, and formation of metal hydrides and organometallics. Successful approaches that have been implemented to suppress cathodic corrosion are reviewed. We present several examples from electroorganic synthesis where the clever use of alloys instead of soft neat heavy metals and the application of protective cationic additives have allowed to successfully exploit these materials as cathodes. Because of the high overpotential for the hydrogen evolution reaction, such cathodes can contribute toward more sustainable green synthetic processes. The reported strategies expand the applications of organic electrosynthesis because a more negative regime is accessible within protic media and common metal poisons, e.g., sulfur-containing substrates, are compatible with these cathodes. The strongly diminished hydrogen evolution side reaction paves the way for more efficient reductive electroorganic conversions.

The use of electric current in synthetic organic chemistry offers a sustainable tool for the selective reductive synthesis of quinoline N‐oxides starting from easily accessible nitro compounds. The reported method employs mild and reagent‐free conditions, a simple undivided cell, and constant current electrolysis set‐up which provides conversion with a high atom economy. The synthesis of 30 differently substituted quinoline N‐oxides was successfully performed in up to 90 % yield. Using CV studies, the mechanism of the selective formation of the quinoline N‐oxides was elucidated. The technical relevance of the described reaction could be shown in a 50‐fold scale‐up reaction.

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Cathodic synthesis provides sustainable access to 1-hydoxy- and 1-oxy-quinazolin-4-ones from easily accessible nitro starting materials. Mild reaction conditions, inexpensive and reusable carbon-based electrode materials, an undivided electrochemical setup, and constant...