Stability Modulation of Energetic Compounds via Spatial Noncovalent Interactions of N-Amino Groups

The N-amino group has proven to be an effective moiety for enhancing detonation properties, as the N–N single bond serves as a valuable energy storage bond through the formation of stable nitrogen–nitrogen triple bonds upon bond cleavage. However, its relatively weak bond energy poses marked challenges for the formation of N–N single bonds. In this study, we present an energetic molecule, (E)-1,1′-diamino-3,3′-dinitro-5,5′-azo-1,2,4-triazole (3), which incorporates nitro and N-amino groups in an azo-bridged triazole framework, where the N-amino groups are stabilized through space noncovalent interactions. Compound 3 shows good molecular stability with a decomposition temperature of 196 ℃. In addition, it exhibits a superior detonation velocity and low sensitivities (D: 9,156 m s⁻¹; friction sensitivity [FS]: 260 N; impact sensitivity [IS]: 36 J) compared to the high-explosive HMX (D: 9,144 m s⁻¹; FS: 120 N; IS: 7.4 J). The results indicate that compound 3 shows great potential for practical application as a replacement for HMX. Furthermore, the nitramine derivative 4 (D: 9,980 m s⁻¹; P: 46.3 GPa) exhibits outstanding detonation properties, surpassing those of CL-20.