Enforced Planar FOX 7 like Molecules: A Strategy for Thermally Stable and Insensitive p Conjugated Energetic Materials.
Exploring new energetic derivatives of 1,1 diamino 2,2 dinitroethylene (FOX 7) is still a key aspect in the field of energetic materials. However, so far most of the attention has been focused on modification of FOX 7 via different reaction strategies. Now we report the design of three new FOX 7 like compounds (3 5) where one nitro group in FOX 7 is replaced by a nitrogen rich heterocyclic ring. Each of them is characterized by single crystal X ray crystallography. Electronic structures are studied through computational methods in comparison with FOX 7. In addition, the chemical reactivity of 3 was also investigated. Its hydroxylammonium (7) hydrazinium (8) and ammonium (9) salts were prepared and the nitrate product (10) was also isolated. Compound 10 has a C N bond length of 1.577 A that is one of the longest values found for the C NO2 bond. It was found that the incorporation of a tetrazole or triazole ring into the backbone of a conjugated nitroenamine does lead to a planar structure, which not only enhances the thermal stability but also improves the sensitivity of the product.
Journal of the American Chemical Society