Sodium Chloride → 1-Fluoro-1,1,5-trinitro-3-oxa-5azahexane

2-Fluoro-2,2-dinitroethanol (7.62 g, 49.5 mmol) was stirred with acetonitrile (2.5 ml) under nitrogen as 2-nitro-2-azapropyl trifluoroacetate (10.0 g, 49.5 mmol) in acetonitrile (3.5 ml) was added in one portion. The reaction flask was immediately connected to a vacuum pump and brought to 1-2 mm during several minutes. After stirring 22/3 hours, the solution was stirred 1/3 hour at ambient pressure before pouring onto a saturated sodium chloride solution (50 ml), which was extracted with dichloromethane (3×25 ml). The organic portion was washed with a 1:1 mixture of saturated sodium chloride solution: 0.04 N sodium hydroxide solution (10×150 ml), dried with magnesium sulfate, and concentrated to crude 1-fluoro-1,1,5-trinitro-3-oxa-5-azahexane; yield: 8.67 g (72%). Recrystallization from ether/hexane at -78° C. gave 1-fluoro-1,1,5-trinitro-3-oxa-5-azahexane; yield: 7.5 g (63%).