Skeletal Reconstruction of Tetrazole Rings Enables Synthesis of Fused Triazole–Pyrimidine Bicyclic Energetic Materials

Nitrogen-rich triazole-fused energetic materials featuring high heats of formation and extended π-conjugation represent crucial candidates for satisfying the dual requirements of high energy and exceptional insensitivity. However, achieving their effortless synthesis remains challenging. Herein, an efficient skeletal reconstruction strategy based on the thermal cleavage of tetrazole was utilized to synthesize a novel [5,6]-fused triazolopyrimidine explosive, TTO-1, and a plausible transformation mechanism was elucidated by theoretical calculations. Subsequent oxidation and self-assembly derivatization afforded a novel low-sensitivity energetic material, TTO-2, alongside a high-energy material, TTO-3. Both TTO-1 and TTO-2 possess favorable insensitivity (IS > 50 J; FS > 360 N) and detonation performance (P = 23.4 and 26.3 GPa, respectively), positioning them as promising candidates for low-sensitivity energetic materials, while TTO-3 displays a highly competitive detonation performance (P = 35.4 GPa). These findings provide valuable insights for the construction of advanced nitrogen-rich fused high-energy materials.