Insensitive Nitrogen-Rich Energetic Compounds Based on the 5,5′-Dinitro-3,3′-bi-1,2,4-triazol-2-ide Anion

In this contribution the improvements achieved in the synthesis of the thermally stable energetic heterocycle 5,5′‐dinitro‐2H,2′H‐3,3′‐bi‐1,2,4‐triazole (DNBT) are described. The main goal was the synthesis of at least equally stable but more powerful energetic compounds based on the DNBT2– anion in combination with nitrogen‐rich cations. A complete structural and spectroscopic characterization, including IR, Raman, and multinuclear NMR analyses of the uncharged compound is presented. In addition, X‐ray crystallographic measurements on DNBT revealed a very high density of 1.903 g cm–3. To increase both performance and stability, highly nitrogen‐rich salts of DNBT formed from ammonium, hydroxyammonium, hydrazinium, guanidinium, aminoguanidinium and triaminoguanidinium cations were prepared and fully characterized by vibrational and multinuclear NMR spectroscopy, DSC, and X‐ray diffraction measurements. The standard enthalpies of formation were calculated for selected compounds at the CBS‐4M level of theory and the detonation parameters were calculated by using the EXPLO5.5 program. In addition, the impact as well as friction sensitivities and sensitivity against electrostatic discharge were determined. The main goal was to synthesize high thermally stable and powerful energetic compounds based on the DNBT2– anion in combination with nitrogen‐rich cations. A complete structural and spectroscopic characterization of all compounds by IR, Raman, and NMR spectroscopy is presented. The compounds exhibit low sensitivities, high positive heats of formation, and excellent detonation parameters.