Copper-Catalyzed One-Pot Protocol for Reductive N-Arylation of Nitroarenes with (Hetero)aryl Chlorides in Water

A novel protocol for the Cu-catalyzed reductive N-arylation of nitroarenes with (hetero)aryl chlorides in water has been realized. Combining N-(9H-carbazol-9-yl)-6-hydroxypicolinamide (L2) with oxalohydrazide is vital to realize the method at 90 °C with a loading of 5 mol % of Cu₂O/L2. Various nitroarenes and aryl chlorides have been successfully coupled in good to excellent isolated yields. Further, two diarylamine-containing key intermediates, 3f and 4u, have been smoothly synthesized on a gram scale using this method.