2,4,6,8-tetranitro-2,4,6,8-tetraazabicyclo

Delpeyroux and coworkers16 have developed a set of molecular mechanics parameters for nitramines (R—N—NO2) for the EMO program and used it in conjunction with MM2-85 parameters to calculate the structures of 1,4-dinitro-glycoluryl (8), 1,3-dinitro-4,6-diacetylglycoluryl (9) and 2,5,7,9-tetranitro-tetraazabicyclo(4.3.0)nonanone (10). The complete parameter list for the nitramine functionality is provided in Reference 16 but the parameterization procedure is not discussed. 

Tetranitro-2,4,6,8-tetraazabicyclo[3.3.0]octane (bicyclo-HMX) (69) has seen considerable research efforts focused into its preparation. " Interest in bicyclo-HMX arises from its increased rigidity compared to HMX, a property which should result in higher density and... 

Li and co-workers recognised the potential of cyclic IV-nitroureas as energetic materials and reported the synthesis of 2,4,6,8-tetranitro-2,4,6,8-tetraazabicyclo[3.3.0]octane-3-one (109) (K-55) from the nitration of 2,4,6,8-tetraazabicyclo[3.3.0]octane-3-one dihydrochloride (108) with absolute nitric acid in acetic anhydride at room temperature the latter obtained from the condensation of lV,lVL(iiformyl-4,5-dihydroxyimidazolidine (107) with urea in aqueous hydrochloric acid. Pagoria and co-workers " " reported the synthesis of 2,4,6-trinitro-2,4,6,8-tetraazabicyclo[3.3.0]octane-3-one (110) (HK-55) in 72% yield from the nitration of (108) with 90 % nitric acid in acetic anhydride at subambient temperature (Table 5.3). HK-55 has a relatively high density (1.905 g/cm ) coupled with a low sensitivity to shock. 

M. Chen, G. Hua and W. Li, Synthesis and properties of 2,4,6,8-Tetranitro-2,4,6,8-tetraazabicyclo[3.3.0]octan-3-one , in Proc. International Symposium on Pyrotechnics and Explosives, China Academic Publishers, Beijing, China, 187-189 (1987). 

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