Method for preparation of N-nitro-5-azidomethyl-1,3-oxazolidine starting from potassium sulfamate and epichlorohydrin via heterocyclization, nitration and azidation as key steps.

Abstract

The invention relates to a method for the synthesis of N-nitro-5-azido-methyl-1,3-oxazolidine (I) which can be used as an energetic plasticizer for polymers. The starting compds. used are potassium sulfamate and epichlorohydrin. The regioselective addn. reaction of potassium sulfamate to epichlorohydrin/ring opening takes place at 50-53°C during 50-55 h with threefold excess of potassium sulfamate. Without purifn., a water-alc. soln. of intermediate N-(3-chloro-2-hydroxypropyl)potassium sulfamate is condensed with formaldehyde (30% aq. soln.) to afford N-(5-chloromethyl-1,3-oxazolidine)potassium sulfamate (II) which after evapn. of solvents. is suspended in acetic anhydride and nitrated with nitric acid at 10-25°C. The intermediate N-nitro-5-chloromethyl-1,3-oxazolidine is extd. with organochlorine solvents, purified by treating with aq. sodium hydroxide soln. at 70-75°C followed by azidation with sodium azide in DMF medium in the presence of activated carbon at 100°C to yield I in 81.5% yield (last step). [on SciFinder(R)]