Research Progress in Electrochemical Synthesis of Azo Bridged Nitrogen-Containing Heterocyclic Energetic Compounds

Azido-bridged nitrogen-rich heterocyclic energetic compounds have high heat of formation and low mechanical sensi- tivity,making them widely applicable in the field of energetic materials. However,traditional preparation methods often involve oxidative coupling,which poses high safety risks and severe environmental pollution. In contrast,the electrochemical synthesis method is favored by researchers for its efficiency,controllability,and environmental friendliness. By adjusting the electrochemi- cal reaction conditions,selective synthesis of azido-bridged nitrogen-rich heterocyclic energetic compounds with different struc- tures can be achieved,opening up new possibilities for their synthesis. This study reviews the electrochemical synthesis meth- ods,effects of electrolytes and electrodes,and possible reaction mechanisms of azido-bridged nitrogen-rich heterocyclic energet- ic compounds such as furazan,pyrazole,1,2,4-triazole and tetrazole. Additionally,future research directions are proposed,in- cluding the electrochemical preparation of energetic molecules that cannot be synthesised by traditional methods,the construc- tion of nitrogen-nitrogen bonds,carbon-nitrogen bond through electrochemical method,and the synthesis of various fused/ bis-heterocylcic energetic compounds. Furthermore,the scaled-up synthesis of these compounds via the electrochemical method is also discussed. The study provides a reference for the research and development of electrochemically synthesized azido-bridged rich nitrogen-containing energetic molecules. © 2024 Institute of Chemical Materials, China Academy of Engineering Physics. All rights reserved.