Synthesis of melt-castable gem-dinitro derivatives of 4,5,6,7-tetrahydrobenzofurazan and its N-oxide

The synthesis of energetic compounds of the gem -dinitrocarbocycle family, furazan and furoxan fused to dinitrocyclohexane, is reported. The construction of the gem -dinitro moiety was achieved by nitration of the hydroxyimine group by using both fuming and dilute nitric acid. These hybrid materials were characterized with respect to their spectral and energetic materials properties. The structural features of furazan 5 and furoxan 6 were revealed using X-ray crystallography. Energetic compound 5 was found to exhibit melt-castable properties, with a melting point of 78 °C and an onset decomposition temperature of 198 °C. It was insensitive to impact, with a calculated detonation pressure ca . 21% higher than the benchmark melt-castable explosive TNT. Energetic bicyclic gem -dinitrocyclohexanes, comprising a furazan or furoxan moiety, have been synthesized starting from commercially available cyclohexanone in three steps.