A heat-resistant explosive featuring an N,N′-ethylene bridged 1,2,4-1H-triazole fused ring

Abstract

Six energetic compounds bridged by N,N′-alkyl groups were synthesized in a straightforward manner in 1–3 steps from 3-nitro-1H-1,2,4-triazol-5-amine (ANTA). Among these compounds, 2,7-dinitro-10,11-dihydrobis([1,2,4]triazolo)[5,1-c:1′,5′-g][1,2,4,7]tetrazocine (2) exhibits a decomposition temperature exceeding 300 °C (T_d(onset) = 319 °C), with superior density and detonation performance (ρ = 1.83 g cm⁻³, D_v = 8157 m s⁻¹) to HNS. N,N′-(Methylenebis(3-nitro-1H-1,2,4-triazole-1,5-diyl))dinitramide (5) has the highest density (ρ = 1.91 g cm⁻³) with the best comprehensive detonation performance (D_v = 9079 m s⁻¹, P = 36.1 GPa), and is comparable to HMX. Insight into the relationship between stability and structure revealed that 1,2,4-triazole-based compounds with an N,N′-ethylene bridge consistently exhibit superior stability compared to those with an N,N′-methylene bridge. This provides a new way to design fused ring explosives with high stability.