A Promising Strategy toward the Development of C–C- and C–N-Linked Tricyclic Tetrazole Energetic Materials with High Energy Density

Tetrazole-based energetic materials have received extensive attention from researchers due to their high heats of formation and high nitrogen contents. In this work, a novel tricyclic tetrazole compound linked by C–C and C–N bonds was synthesized for the first time, and a series of energetic salts (1–4) were prepared. In addition, the energetic compound 2,2′-bis(dinitromethyl)-2H,2′H-5,2′-5,5′-tertetrazole (DNTBT) was synthesized by assembling dinitromethyl with tricyclic tetrazole. Among them, six compounds were further determined by single-crystal X-ray diffraction analysis. And theoretical calculations demonstrate that all compounds exhibit high positive heat of formation. The heats of formation of all target compounds are much greater than those of RDX, HMX, and CL-20. The computational results indicate that DNTBT (D = 9580 m·s^–1, P = 39.2 GPa) and its ionic salts 6 (D = 9038 m·s^–1, P = 34.4 GPa), 7 (D = 9178 m·s^–1, P = 35.2 GPa), and 8 (D = 9297 m·s^–1, P = 37.7 GPa) exhibit superior detonation performance compared to HMX (D = 8795 m·s^–1, P = 34.9 GPa) and are comparable to RDX (D = 9144 m·s^–1, P = 39.2 GPa). This work provides guidance for future researchers in developing high-energy-density materials.