Synthesis and Characterization of 4-(1,2,4-Triazole-5-yl)furazan Derivatives as High-Performance Insensitive Energetic Materials.

3-Nitro-4-(5-nitro-1,2,4-triazol-3-yl)furazan (2), N,N'-bis(trinitroethyl)-3,5'-diamino-4-(1,2,4-triazol-3-yl)furazan (3), N,N'-bis(trinitroethyl)-3,5'-dinitramino-4-(1,2,4-triazol-3-yl)furazan (4) and eighteen nitrogen-rich salts (5 a, 5 b, 5 d-5 i, 5 g-1, 6 a-6 i) were designed and synthesized. These 4-(1,2,4-triazole-5-yl)furazan derivatives were fully characterized by IR and NMR spectra, elemental analysis, and differential scanning calorimetry (DSC). The solid-state structures of 2, 5 d, 5 e, 5 h, 5 g-1, 6 g, and 6 i were confirmed via single crystal X-ray analysis. Detonation performance (detonation velocities and pressures) of these energetic compounds was evaluated and the impact and friction sensitivities were measured using standard BAM technology. Some of the compounds, for example, 2 (D: 9152 m s-1 , P=37.1 GPa) and 4 (D: 9355 m s-1 , P=40.1 GPa) exhibit excellent detonation performance, which are comparable to the highly explosive benchmarks such as RDX (D: 8795 m s-1 , P=34.9 GPa) and HMX (D: 9144 m s-1 , P=39.2 GPa).