Incorporating Energetic Moieties into Four Oxadiazole Ring Systems for the Generation of High-Performance Energetic Materials.

The synthesis of three neutral 3,3'-di(1,2,5-oxadiazol-3-yl)-5,5'-bi(1,2,4-oxadiazole) structures in combination with different energetic moieties such as nitramino, trinitroethylamino, and N-nitrated trinitroethylamino is presented. In addition, a novel family of energetic salts based on 4,4'-([5,5'-bi(1,2,4-oxadiazole)]-3,3'-diyl)-bis(1,2,5-oxadiazol-3-nitramide) is synthesized. The new compounds (4, 6-18) are characterized by IR and multinuclear NMR spectroscopy and elemental analysis. The structures of 4⋅2 C4 H8 O2 , 9, 13, 15, and 16 are further confirmed by single-crystal X-ray diffraction studies. The thermal stabilities of 4 and 6-18 are determined by differential scanning calorimetry. Most of the new compounds have high densities (1.72-1.93 g cm-3 ) measured using a gas pycnometer (25 °C). Energetic evaluation indicates that they also have good detonation pressures and velocities (P: 26.4-41.9 GPa; D: 8218-9550 m s-1 ).