Ammonia → Azanium nitramide

Temperature

-50 °C

This solution was then added to a suspension of 7.5 grams (49.7 mmoles) of the ammonium N-nitrourethane prepared in Example I and suspended in 200 ml of methylene chloride which had been previously cooled to -50° C. before the addition. The reaction was allowed to proceed for one hour, warming to -30° C. over that hour. Excess ammonia gas was then added to raise the pH to 10. The solution was then filtered and the insoluble material was collected and digested 20 min in 150 ml of acetonitrile. The resulting suspension was filtered, and the filtrate was passed through a 4"×1" column of 230-400 mesh silica-gel, eluting with CH3CN. The filtrate was concentrated to 30 ml and treated with 30 ml CHCl3, resulting in the precipitation of 4.0 g of pure crystalline ammonium dinitramide mp 90-93° (60% yield).