Abstract
1,1-Diamino-2,2-dinitroethene (FOX-7), is an insensitive energetic material developed by the Swedish Defense Agency (FOA) in 1998. FOX-7, a "push-pull" nitroenamine, possesses a unique structure with interesting chemical properties that have not been fully understood. Its chemical unpredictability and poor solubility in common organic solvents have made the study of its chemical reactivity challenging. In our efforts to expand the chemistry of FOX-7 and to develop derivatives with superior energetic performance, we initiated work to develop the following areas: (1) Metal and salt chemistry, (2) FOX-7 based oxidizers, and (3) Azo-bridged derivatives of FOX-7.
Prior to our work, the only known metal chemistry of FOX-7 involved its potassium salt, KFOX, and no literature precedent had been found for the azo derivatives of FOX-7. We have been able to synthesize various silver and copper metal complexes of FOX-7 from simple amines via metathesis reactions. The completion of this work gave rise to the first metal complexes of FOX-7 and insight into of the behavior of FOX-7 as a coordinating ligand and an anion. In route to synthesizing desired azo-bridge substrates, we uncovered a new family of halogenated FOX-7 and halogenated azo-bridged FOX-7 derivatives. One of the most interesting features of this work was the discovery that these halogenated FOX-7 and halogenated azo-FOX-7 compounds behaved as hypergolic oxidizers. This is a new property of FOX-7 derivatives that had yet to be reported. Our contributions to the metal and azo chemistry of FOX-7 will be discussed.