Synthesis and Properties of Two 1，2，5-Oxadiazole based Energetic Salts with Nitrogen-Rich Fused Ring Skeleton

Two nitrogen-rich energetic salts，5，5′- （hydrazine-1，2-diyl）bis（5，7-dihydro- [1，2，5]oxadiazolo[3，4-e][1，2，4]tri- azolo[4，3-a]pyrimidine-8（4H）-one）perchlorate（2）and 5，5′- （diazene-1，2-diyl）bis（[1，2，5]oxadiazolo[3，4-e][1，2，4]triazolo[4，3-a]pyrimidine-8（7H）-one）nitrate（3）were accomplished from the raw material of 5，6-diamino- [1，2，5]oxadiazolo[3，4-b]pyrazine（1）. Structure characterization of energetic ionic salts 2 and 3 were achieved through various techniques，including Nuclear Magnetic Resonance Spectroscopy （NMR），Fourier Transform infrared spectroscopy （FTIR），elemental analysis （EA）and X-ray single crystal diffraction（XRD）. Their thermal decomposition behaviors were investigated using differential scan - ning calorimetry（DSC）method，while their friction and impact sensitivities were identified according to BAM standard test meth - ods. Moreover，their detonation performances were predicted based on the combination of Isodesmic Reactions and EXPLO 5 software. The results prove that compounds 2 and 3 crystallize in the monoclinic system，belonging to space groups Pn and P21/n，respectively. The cationic parts of their crystal structures show good planarity and intensive hydrogen bonds in the crystal packing are observed. The thermal decomposition temperatures of compounds 2 and 3 are 154 ℃ and 130 ℃，respectively. Their theoretical detonation velocities are 7722 m·s-1 and 8008 m·s-1，while their theoretical detonation pressures are 26.3 GPa and 28.4 GPa，respectively. Their friction sensitivities are both 360 N，and impact sensitivities are greater than 40 J. Compounds 2 and 3 outperform traditional explosives TNT in terms of detonation performance，friction sensitivity，and impact sensitivity. © 2024 Institute of Chemical Materials, China Academy of Engineering Physics. All rights reserved.