Design, synthesis and characterization of a carbonyl-containing high-density pyrazolotriazine-based energetic...

Constructing novel high-energy frameworks to achieve an ideal balance between high energy density and good stability is a common goal in the field of energetic materials. In this study, a novel high-energy density compound was designed and synthesized by introducing carbonyl groups into a fused pyrazolotriazine. Its crystal structure shows that the compound formed compact planar stacking. A three-dimensional intermolecular network through hydrogen bonding and π-π interactions was constructed, resulting in its high density of 1.92 g cm^-3. The compound possesses good detonation performances (detonation velocity: 8430 m s^-1, detonation pressure: 28.5 GPa), a high decomposition temperature of 210 °C and low sensitivities (impact sensitivity >40 J, friction sensitivity >360 N), which are superior to those of conventional explosives like TNT. This study demonstrates the feasibility of introducing carbonyl groups into nitrogen-rich fused systems to achieve a balance between high energy and low sensitivity.