Energetic salts of 4-nitramino-3-(5-dinitromethyl-1,2,4-oxadiazolyl)-furazan: Powerful alliance towards good thermal stability and high performance

Two different methods were developed to synthesize 4-amino-3-(5-acetic acid methyl ester-1,2,4-oxadiazolyl)-furazan (1), the precursor to prepare 4-nitramino-3-(5-dinitromethyl-1,2,4-oxadiazolyl)-furazanate, in scalable good yields. In four steps, three energetic salts were obtained with an overall yield of ∼50% and show promising characteristics of typical secondary explosives. The structure of the diammonium salt (2a) was confirmed by X-ray single crystal diffraction. It has a high crystal density of 1.840 g cm^-3 at 150 K and a measured density of 1.804 g cm^-3 at room temperature. All of the compounds were fully characterized by infrared spectroscopy (IR), ¹H NMR, and ¹³C NMR spectroscopy as well as elemental analysis. Compound 2b and 2c exhibit better sensitivities and comparable detonation properties relative to HMX, showing great promise as replacements.