Novel catenated N6 energetic compounds based on substituted 1,2,4-triazoles: synthesis, structures and properties

Abstract

1-Amino-3,5-dinitro-1,2,4-triazole (ADNT) was prepared using an efficient N-amination process. Three novel catenated N₆ energetic derivatives of ADNT, which contain 1,1′-azobis(3,5-dinitro-1,2,4-triazole) (ABDNT), 1,1′-azobis(3-chloro-5-nitro-1,2,4-triazole) (ABCNT) and 1,1′-azobis(3,5-diazido-1,2,4-triazole) (ABDAT), were synthesized from N-amino oxidative-coupling reactions of ADNT. All compounds were fully characterized by ¹H and ¹³C nuclear magnetic resonance spectroscopies, infrared spectroscopy, elemental analysis, mass spectrum, as well as differential scanning calorimetry (DSC). The crystal structure of compound ABCNT was confirmed by single-crystal X-ray diffraction showing an extensive conjugated structure. The densities of energetic derivatives ranged from 1.71 to 1.93 g cm⁻³, and all compounds have positive heats of formation in the range of 774.8 to 2150.8 kJ mol⁻¹. Based on the measured densities and calculated heats of formation, theoretical performance calculations, including detonation pressures (29.6–42.4 GPa) and detonation velocities (8.22–9.49 km s⁻¹) were carried out using the Gaussian 09 program and Kamlet–Jacobs equations, and they compared favorably with those of TNT and RDX. These properties make them potentially competitive as new high energy-density compounds.