4H-[1,2,3]Triazolo[4,5-c][1,2,5]oxadiazole 5-oxide and Its Salts: Promising Multipurpose Energetic Materials

A smooth synthesis of 4H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole 5-oxide 1 and its energetic salts (ammonium, hydroxylammonium, guanidinium, triaminoguanidinium) is reported. The compounds synthesized were characterized by multinuclear nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy, mass spectrometry, elemental analysis, differential scanning calorimetry, single-crystal, and powder X-ray diffraction. All the compounds possess a beneficially high enthalpy of formation (88.9–168.0 kcal·mol–1). These data, in combination with the experimentally determined densities (1.702–1.934 g·cm–1), were used to calculate the detonation pressures (33.9–43.1 GPa) and velocities (8.86–9.31 km·s–1). The majority of the synthesized energetic salts had moderate impact and friction sensitivity, which made them promising candidates for various energy applications, including their use as components of solid composite propellants. It was shown that compounds 1 and 2c–f had higher energetic characteristics as components of solid composite propellants (the specific impulse was higher by 5–10 s) than HMX or CL-20 in propellant formulations.