Electrochemical Deoxygenation of Aromatic Amides and Sulfoxides

The electrochemical deoxygenation of a broad range of aromatic amides was achieved under mild conditions on lead cathodes. Under the optimized reaction conditions, acetal, thienyl, and ether moieties are tolerated. Furthermore, the reduction protocol can be applied to aromatic and aliphatic sulfoxides to obtain the corresponding sulfides. For both aromatic amides and sulfoxides, the deoxygenation reaction ensues without the use of expensive catalysts or hazardous reducing agents. Owing to the high selectivity of the process, simple extraction is sufficient to isolate the product from the substrate. The straightforward purification protocol, the coformation of water, and the use of electric current instead of reducing agents render our method environmentally friendly and economically beneficial. The electrochemical deoxygenation of a broad range of aromatic carboxamides is achieved under mild conditions. Furthermore, sulfides can be readily prepared by subjecting the corresponding sulfoxides to the elaborated electroreductive strategy.