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As a high energy density materials , 2,4,6,8 - tetranitro -2,4,6,8 - four -azabicyclo [ 3.3.0] octane (commonly known as bicyclo - HMX ) has high regard in Energetic Materials scientists' concerns . The paper by inverse synthetic analysis to determine the preparation of bicyclo -HMX three potential precursors : 2,4,6,8 - tetra-acetyl -2 ,4,6,8 - 4 -azabicyclo [ 3.3.0 ] oct- alkoxy ( I ) , 2,4 - dinitro -6 ,8 - diacetyl -2 ,4,6,8 - 4 -azabicyclo [3.3.0 ] octane ( II ) and 2,4 - Dinitromethylene yl -6,8 - dipropyl acyl - 2 ,4,6,8 - tetrakis -azabicyclo [3.3.0 ] octane ( III ) . 2,4,6,8 - tetraacetyl -2,4,6,8 - 4 -azabicyclo [ 3.3.0 ] octane ( I ) through a four-step condensation reaction , the preparation process has undergone methylenebis acetamide , 1,3 - diacetyl -4 ,5 - dihydroxy 1,3 - diaza- cyclopentane and 1,3 - diacetyl -4 ,5 - acetoxy - 1 ,3 - diaza to cyclopentane three intermediate . Method using toluene azeotrope with water , the water generated by the reaction of formaldehyde and acetic acid amide from the reaction system with a to procure methylene diethylamide constantly generated , its yield is increased from 16% to 91 % . Through optimization of the steps of the preparation conditions , the Ⅰ four step yield was prepared from 4% up to 14%. 2,4 - dinitro -6 ,8 - diacetyl -2 ,4,6,8 - 4 -azabicyclo [3.3.0 ] octane (Ⅱ) and 2,4 - dinitro - 6 ,8 - dipropionyl -2,4,6,8 - Four -azabicyclo [ 3.3.0] octane ( III ) preparation method is not publicly reported literature , the paper explored methods for their preparation . Successfully prepared 3,5 - diacetyl 3,5 - azacyclopentyl dilute ( IV ) , 3,5 - -3,5 of dipropionyl - two azacyclopentyl dilute ( V ) , 1,4 - diacetyl -2,3 - dichloro-1 ,4 - azacyclopentane ( VI ) and methylene dinitramide amine ( VII ) . Ⅳ use of the dibromo derivative or Ⅵ Ⅶ triethylamine catalyzed condensation preparation Ⅱ No target to obtain a portion of the hydroxyl group-containing decomposition products ; the Ⅴ triethylamine catalytic dibromo derivatives and Ⅶ prepared by condensation of III get just some of the carboxylic acid derivatives . Select three different nitrification system I nitration , Ⅰ during nitrification broken ring , did not give the desired compound bicyclo - HMX .
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