A good balance between the energy density and sensitivity from assembly of bis(dinitromethyl) and bis(fluorodinitromethyl) with a single furazan ring

In the field of energetic materials, the contradiction between energy density and sensitivity has long baffled the researchers in pursuing the high detonation-performance compounds with low sensitivity. The bis(dinitromethyl) and bis(fluorodinitromethyl) groups were introduced into a single 1,2,5-oxadiazole (furazan) ring for the first time to form a series of novel furazan-based energetic derivatives, which have been fully characterized by NMR, FTIR, elemental analysis and single crystal X-ray diffraction. The thermal decomposition behaviors were also investigated by multiple heating methods and TG-DSC. Interestingly, among these newly as-synthesized compounds, the dihydroxylammonium salt of bis(dinitromethyl)-furazan (5) possessed a high crystal density of 1.938 g cm⁻³ at room temperature and exhibited excellent detonation properties (v_D = 9679 m s⁻¹, P = 41.5 GPa), as well as moderate impact sensitivities (14 J), which achieved a high level of balance between high energetic density and low sensitivity to date for the furazan-based energetic salts. Furthermore, the neutral compound bis(fluorodinitromethyl)-furazan (11) showed a high positive oxygen balance of 10.19%, which also makes it a potential candidate for the high energetic oxidizer. Such fascinating properties demonstrate that the assembly of bis(dinitromethyl) groups with the single furazan ring is a favorable strategy for the design and synthesis of novel energetic materials with high energy and improved safety.