Toward Advanced High-Performance Insensitive FOX-7-like Energetic Materials via Positional Isomerization.

For an energetic molecule with a definite elemental composition, the substituent type and position are the most important factors to influence its detonation performance and mechanical sensitivities. In this work, two pairs of FOX-7-like energetic isomers based on ( 2 and HTz-FOX ; 5 and 6 ) were synthesized and characterized. Through positional isomerization, advanced high-performance insensitive explosives were obtained. Compounds 2 and 5 with an amino group adjacent to the electron-withdrawing side of the ethene bridge show both higher thermal stability and lower mechanical sensitivities ( 2 : T d = 258 °C, impact sensitivity ( IS ) = 25 J, and friction sensitivity ( FS ) = 300 N; 5 : T d = 264 °C, IS = 30 J, and FS = 320 N). In addition, 2 shows ultrahigh detonation performance ( D v = 9224 m s -1 and P = 31.1 GPa). These promising physicochemical properties are comparable to those of HMX ( D v = 9193 m s -1 , P = 37.8 GPa, T d = 275 °C, IS = 7.4 J, and FS = 120 N), which suggests that 2 may be a promising energetic material in future applications.