Dinitromethyl‐3(5)‐1,2,4‐oxadiazole Derivatives from Controllable Cyclization Strategies

N ‐Cyanoimidate ( 1 ) with hydroxylamine hydrochloride in the presence of triethylamine gives different products ( 2 a or 2 b ) as a function of the sequence of reactant addition. Further oxidation/nitration/decarboxylation/acidification reactions of 2 a / 2 b generate dinitromethyl‐3(5)‐1,2,4‐oxadiazole derivatives, including a surprising energetic compound with high oxygen balance, 3‐(dinitromethyl)‐1,2,4‐oxadiazol‐5‐one ( 5 ) as well as 5,5′‐dinitromethyl‐3,3′‐azo‐1,2,4‐oxadiazole ( 9 ). Some salts of 5 and 9 as precursors were also prepared. All were fully characterized using multinuclear NMR and IR spectroscopy, and elemental analyses as well as low‐temperature single‐crystal X‐ray diffraction for 4 , 5 , 7 and 8 . In addition, their properties (thermal stability, detonation performance and sensitivity to impact and friction) were investigated. Among them, 5 and 8 show promising detonation performance as energetic materials.