Facile synthesis of thermally stable tetrazolo[1,5-b][1,2,4]triazine substituted energetic materials: synthesis and characterization

Abstract

Various thermally stable energetic materials with high nitrogen content, low sensitivity and better detonation performance were synthesized. The versatile functionalization of 1,2,4-triazine involving the introduction of oxadiazole and tetrazole is discussed. All the compounds were fully characterized using IR, multinuclear NMR spectroscopy, elemental analysis, and high-resolution mass spectrometry. Compounds 2, 3, 9 and 12 were further verified using single-crystal X-ray analysis. Compound 9 can be considered a melt-cast explosive due to its lower onset melting temperature (112 °C). The detonation velocity, pressure, density, and heat of formation of all the synthesized compounds range between 7056 and 8212 m s⁻¹, 17.57 and 23.78 GPa, 1.70 and 1.81 g cm⁻¹, and 43 and 644 kJ mol⁻¹, respectively. Due to the high nitrogen percentage (53 to >72%), these molecules can be used in car airbag applications. Due to the high thermal stability (>220 °C) and lower sensitivity, these compounds can be potentially used as high-performing thermally stable secondary energetic materials.