Palladium-mediated base-free and solvent-free synthesis of aromatic azo compounds from anilines catalyzed by copper acetate

Herein, we report a new one-step direct synthesis of aromatic azo compounds from anilines under mild conditions. With the catalysis of copper acetate mediated by palladium salt, rapid conversion of anilines to aromatic azo compounds can be observed under the conditions of base-free along with solvent-free. Furthermore, the cross-coupling nitridation reaction based on this strategy was also studied. This research provides not only a new way for the synthesis of symmetrical and asymmetrical aromatic azo compounds but also a strategy and platform for exploring catalytic applications of transition metal compounds.