Efficient preparation and comprehensive properties of thermal decomposition and detonation for 4,4″-dinitro-3,3″-azofuroxan

The preparation of 4,4′-dinitro-3,3′-azofuroxan (3) was efficiently accomplished from synthesizing the key intermediate of 4-amino-3-azidocarboxyl-furoxan (1) and oxidizing the precursor 4,4′-diamino-3,3′-azofuroxan (2). The structure of 3 and its crystal density of 1.981 g cm⁻³ were determined by single crystal X-ray diffraction studies. The crystal structure determination indicated that only 3 was obtained rather than its isomers 3,3′-dinitro-4,4′-azofuroxan (3′), which consistent with the results of theoretical calculations. The comprehensive thermal decomposition behaviors were fully characterized by multiple heating methods, TG–DSC-MS and original temperature-dependent/FTIR coupling technique. In addition, the experimental detonation velocity of 3 was determined to be 9778 m s⁻¹ by using a developed method that only requires a small amount of samples on a network plate made of aluminum alloy, which is also well suited for other energetic compounds with high impact sensitivity (IS < 8 J), such as HMX, RDX and CL-20.