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.