High Heat of Detonation Energetic Material Based on Oxadiazoles and Nitroform Groups with Zero Oxygen Balance

An effective strategy for enhancing the heat of detonation is to incorporate high-enthalpy backbone structures while maintaining an oxygen balance close to zero. This approach maximizes energy release while supporting favorable decomposition characteristics. Consequently, 3,4-bis(5-(trinitromethyl)-1,2,4-oxadiazol-3-yl)-1,2,5-oxadiazole 2-oxide (<b>4</b>) was synthesized, which combines three oxadiazole rings and two nitroform groups. A series of energetic salts (<b>3</b>, <b>5</b>-<b>7</b>) corresponding to the dinitromethyl derivative of <b>4</b> were also studied. The structures of compounds <b>3</b> and <b>4</b> were determined through a single-crystal diffraction analysis. Notably, compound <b>3</b> exhibits pores situated between its molecules and is categorized as a hydrogen-bonded organic framework (HOF). This characteristic imparts compound <b>3</b> with a lower mechanical sensitivity, indicated by its impact and friction sensitivity (IS = 25 J, FS>360 N). Compound <b>4</b> exhibits a markedly enhanced theoretical heat of detonation (6949 kJ kg^{- 1}), surpassing that of CL-20 (6534 kJ kg^{- 1}) and achieving the highest heat of detonation among other structurally analogous compounds. This comparison highlights its potential as a valuable contributor to the synthesis of high-energy compounds with enhanced heat detonation characteristics.