An interesting 1,4,2,5-dioxadiazine-furazan system: structural modification by incorporating versatile...

Herein, the 1,4,2,5-dioxadiazine ring is combined with two furazan rings. Interestingly, the structure of the 1,4,2,5-dioxadiazine-furazan system can be modified by incorporating versatile functionalities. The N-trinitroethylamino functionalization derivatives and energetic salts based on 3,6-bis(4-amino-1,2,5-oxadiazol-3-yl)-1,4,2,5-dioxadiazine are investigated. Derivatives of these functionalities are synthesized and fully characterized via multinuclear NMR spectroscopy, IR spectroscopy, and elemental analysis. The structures of compounds 1-7 are further confirmed by single-crystal X-ray diffraction. Compounds 1-12 have moderate thermal stabilities (143-177 °C, except 2 (114 °C), and 3 (88 °C)) and exhibit acceptable sensitivities (IS 3.52-16.3 J and FS 100-240 N). Based on the measured densities (1.73-1.95 g cm^-3) and heats of formation (573.5-2065.4 kJ mol^-1), the detonation velocities (D 8519-9563 m s^-1) and pressures (P 29.3-43.3 GPa) are calculated. Among them, the trinitroethylamino derivative 1 and ammonium salt of 3,6-bis(4-nitroamino-1,2,5-oxadiazol-3-yl)-1,4,2,5-dioxadiazine 5 show a layered assembly of the 1,4,2,5-dioxadiazine-furazan system. These two compounds show good thermal stabilities (1, 154 °C and 5, 177 °C) and relatively low sensitivities (1, 16.3 J and 5, 13.4 J). These properties indicate that the layer assembly structure is helpful to improve the thermal stabilities and result in low sensitivities for the corresponding compounds.