Amination of nitro-substituted fused triazole: A facile refinement for enhanced comprehensive performance

Abstract

The fine-tuning of the molecular structures of current explosives to reduce their inherent defects has proven to be an effective synthetic strategy for producing novel energetic compounds with superior overall performance. In this study, this strategy was adopted to modify the heat-labile nitro-substituted fused triazole through facile C-amination and N-amination, resulting in the synthesis of HANTT and ADNTT, respectively, both demonstrating a total yield exceeding 43 %. HANTT, ADNTT, and their derivates were fully characterized by IR, 1H and 13C spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, and elemental analysis. NCI and Hirshfeld surfaces analysis were employed to explore the intermolecular interactions, while LOL-π, NICS, and ICSS analysis were performed to evaluate the aromaticity and stability of these compounds based on their respective single-crystal structures. Most of these insensitive compounds exhibit good thermostability (168–269 °C) and favorable detonation performances (20.2–32.1 GPa and 7679–8862 m s−1). Attributing to its highest heat of formation (545.2 kJ mol−1) among all new energetic compounds, triaminoguanidinium salt 6, with decent thermostability (Td = 203 °C), exhibits an excellent detonation velocity (vD = 8862 m s−1) superior to that of military benchmark explosives RDX (1,3,5-trinitro-1,3,5-triazacyclohexane), thus highlighting its potential as a high-energy insensitive explosive.