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.