Copper-catalyzed chelation-assisted synthesis of unsymmetrical aliphatic azo compounds

An unprecedented and convenient synthetic approach to a new class of unsymmetrical azo compounds is developed through a chelation-assisted copper-catalysis using cheap commercial reagents. The reactions proceed rapidly at room temperature (typically one hour) and were performed in aqueous medium as well as in solvent-free conditions, delivering structurally diverse alkyl aryl azo compounds in good yields. It has been observed that these novel pyridine hinged azo derivatives exhibit “turn on” fluorescence response in the presence of copper(II) ion in aqueous medium.