| 2,4,6,8-tetranitro-2,4,6,8-tetraazabicyclo[3.3.0]octane(bicyclo-HMX) that attractes the scientists of energetic material fields is a kind of high energy density material(HEDM). After the detailed analysis of the synthetic routes, three potential precursors of bicyclo-HMX may exist which are 2,4,6,8-tetraacetyl-2,4,6,8-tetraazabicyclo[3.3.0]octane(I). 2.4-dinitro-6,8-diacetyl-2,4,6,8-tetraazabicyclo[3.3.0]octane(II), and 2,4-dinitro-6,8-diprop-y1-2,4,6,8-tetraazabicyclo[3.3.0]octane(III).2,4,6,8-tetraacetyl-2,4,6,8-tetraazabicyclo[3.3.0]octane(â… ) can be obtained through four condensations.Three precursors are got in this route which are methylenebisaceta-mide, 1,3-diacetyl-4,5-dihydroxyimidazolidine and 4,5-diacetoxy-1,3-diacetylimidazolidine. The reported yield of this route is low(4%) because of the poor yield of methylenebi-sacetamide.In this paper, toluene is applied to separate water from the reaction which gives a promising yield(91%) of methylenebisacetamide. After the optimization of the other reaction conditions, a better yield(14%) of the four condensation route is got.The methods for preparation of II and III have not been reported. In this paper, we prepared 3,5-diacetyl-3.5-diazacyclopentene(IV),3,5-dipropyl-3,5-diazacyclopentene (V), 1,4-diacetyl-2,3-dichlorine-1,4-diazacyclopentane(VI) and methylenedinitroamine(VII) as the precursors ofâ…¡and III.â…¡is not abtained by condensation of IV's bromine derivative or VI and VII. only the product substituted with-OH is separated. The pr-aperation of III is not successful, there may lies in the reason that-COOH is got by condensation V'bromine derivative and VII.Three different nitration systerms are applied to the praperation of bicyclo-HMX from I, but nothing is abtained duing to the cracking of I. |
