Energetic Salts Based on a Bicyclic Nitrogen-Rich Compound with Good Molecular Stability

To achieve a balance between detonation properties and molecular stability, a series of (1,2,4-oxadiazole)-bridged pyrazole derivatives have been synthesized in this work. The compounds involved were characterized by NMR spectroscopy (1H, 13C), IR spectroscopy, and differential scanning calorimetry (DSC), and the molecular structures of the energetic salts were further confirmed by X-ray single-crystal diffraction. These energetic derivatives have good thermal stability and low sensitivities to impact and friction, which are supported by calculations very well. In particular, perchlorate 6 with the highest decomposition temperature of 331.7 °C has a better thermostability than other reported perchlorate salts. In addition, their detonation velocity (D) and pressure (P) were calculated using EXPLO5 to be around D = 7712–8693 m s–1 and P = 24.0–34.2 GPa, respectively, showing the potential to be new energetic candidates.