Английская Википедия:Bis-oxadiazole
Bis-oxadiazole, or more formally known as bis(1,2,4-oxadiazole)bis(methylene) dinitrate, is a nitrated heterocyclic compound of the oxadiazole family.[1]
Bis-oxadiazole is related to bis-isoxazole tetranitrate (BITN), which was developed at the United States Army Research Laboratory (ARL). With a high nitrogen content, these compounds are poised to release a large volume of very stable N2.[2] It is a “melt-cast” explosive material that is potentially both more powerful and environmentally friendly alternative to TNT.[3]
Synthesis
Glyoxal condenses with hydroxylamine to yield diaminoglyoxime (DAG). Treating DAG with methyl glycolate in the presence of base at high temperature yields bis(1,2,4-oxadiazole).[4]
Replacement for TNT
TNT is attractive explosive because it is a melt-castable. A low melting point of about 80 °C and high decomposition temperature of 295 °C allows manufacturers to safely pour TNT into molds. The production of TNT generates hazardous waste, e.g. red water and pink water.[1]
Bis-oxadiazole, which is also melt-castable, is about 1.5 times more powerful than TNT and yet produces less hazardous wastes.[1]
| Physical Property | bis-oxadiazole | TNT |
|---|---|---|
| Onset temperature of melting | 84.5 °C | 80.4 °C |
| Onset temperature of decomposition | 183.4 °C | 295.0 °C |
| Derived density from X-ray data | 1.832 g cm−3 | 1.65 g cm−3 |
| Detonation pressure | 29.4 GPa | 20.5 GPa |
| Detonation velocity | 8180 m s−1 | 6950 m s−1 |
| Molar enthalpy of formation | -79.4 kJ mol−1 | -59.3 kJ mol−1 |
A major challenge in the production of bis-oxadiazole is its low yield.[5]
References
