Zwitterionic Energetic Materials: Synthesis, Structural Diversity and Energetic Properties

Zwitterionic compounds are an emergent class of energetic materials and have gained synthetic interest of many in the recent years. Due to their better packing efficiencies and strong inter/intramolecular electrostatic interactions, they often ensue superior energetic properties than their salt analogues. A systematic review from the perspective of design, synthesis, and physicochemical properties evaluation of the zwitterionic energetic materials is presented. Depending on the parent ring(s) used for the synthesis and the type of moieties bearing positive and negative charges, different classes of energetic materials, such as primary explosives, secondary explosives, heat resistant explosives, oxidizers, etc., may result. The properties of some of the energetic zwitterionic compounds are also compared with analogous energetic salts. This review will encourage readers to explore the possibility of designing new zwitterionic energetic materials.

Boosting intermolecular interactions of fused cyclic explosives: the way to thermostable and insensitive energetic materials with high density

Improving the packing efficiency of explosives by strong intermolecular interactions can acquire high density while avoiding the expense of stability.

C6N10O4: Thermally Stable Nitrogen-Rich Inner Bis(diazonium) Zwitterions

Two nitrogen-rich inner bis(diazonium) salts, the 4,4'-dinitro-5,5'-diazo-2,2'-bisimidazole (2) and the 4,4'-dinitro-5,5'-diazo-3,3'-bispyrazole (4) zwitterions, are described. Compound 2 was synthesized unexpectedly from the nitration of 4,4'-dinitro-5,5'-diamino-1H,1'H-2,2'-bisimidazole (1) in a mixture of trifluoroacetic anhydride and 100% nitric acid. Both 2 and 4 show good thermal stability, especially 2 has a decomposition temperature of 199 °C, which is the highest one in any of the reported hydrogen-free nitrogen-rich diazonium salts.