New Roles for 1,1-Diamino-2,2-dinitroethene (FOX-7): Halogenated FOX‑7 and Azo-bis(diahaloFOX) as Energetic Materials and Oxidizers

The
syntheses and full characterization of two new halogenated
1,1-diamino-2,2-dinitroethene (FOX-7) compounds and three halogenated
azo-bridged FOX-7 derivatives are described. Some of these new structures
demonstrate properties that approach those of the commonly used secondary
explosive RDX (cyclo-1,3,5-trimethylene-2,4,6-trinitramine). All the
compounds display hypergolic properties with common hydrazine-based
fuels and primary aliphatic amines (ignition delay times of 2–53
ms). This is a new role that has yet to be reported for FOX-7 and
its derivatives. Their physical and energetic properties have been
investigated. All compounds were characterized by single-crystal X-ray
crystallography, elemental analysis, infrared spectra, and differential
scanning calorimetry. These new molecules as energetic materials and
hypergolic oxidizers contribute to the expansion of the chemistry
of FOX-7.