Constructing C-NO2 Pyrazole–Bistetrazole Framework Energetic Materials: Achieve a Balance between Detonation Performance and Sensitivity

Abstract

Balancing detonation performance and sensitivity has always been a challenge in the field of energetic materials. Herein, we present the synthesis of 2-(1H-pyrazol-3-yl)-2H,2′H-5,5′-bistetrazole (4) followed by the introduction of C-NO₂, resulting in the formation of 2-(4-nitro-1H-pyrazol-3-yl)-2H,2′H-5,5′-bistetrazole (5) characterized by low sensitivity, high energy content, and good thermal stability. Characterization of these compounds was conducted via NMR and IR spectroscopy, with the structures of compounds 4a, 5, and 5a elucidated through single-crystal X-ray diffraction. The energetic properties of these compounds were studied, and all new compounds had detonation velocities (7384–9111 m s^–1) higher than trinitrotoluene (TNT). Particularly noteworthy is compound 5b (D_v = 9111 m s^–1, impact sensitivity (IS) = 13 J, friction sensitivity (FS) = 144 N), which exhibits superior detonation velocity and reduced sensitivity compared to Research Department eXplosive (RDX), presenting a promising avenue for the development of novel energetic materials.