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

Abstract

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 DNBT^2– 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.