Study On The Synthesis Of Several Nitrogen-heterocyclic Energetic Compounds

The molecular structure of nitrogen-heterocyclic energetic compounds contains a large number of N-N and C-N bonds.Nitrogen is the main decomposition product,with larger ring tension and higher enthalpy of formation,and the oxygen balance tends to zero or reaches a positive value.These kinds of compounds have huge application value and can expand the category of energetic materials.The synthesis of energetic nitrogen heterocyclic compounds is a research hotspot in the field of energetic materials at home and abroad.In recent years,domestic and foreign scholars have conducted extensive research on various nitrogen heterocyclic rings such as oxadiazole,imidazole,pyrazole,triazole,and tetrazole and so on.This thesis aims at designing and synthesizing high-energy insensitive energetic compounds.It designs some energetic compounds with nitrogen heterocycles as the matrix and introduces other energetic groups or nitrogen heterocycles,and conducts synthetic exploration and analysis.3,4-bis（4-chloro-3,5-dinitro-1H-pyrazol-1-yl）methyl)-furoxan was synthesized using4-chloropyrazole as raw material and its crystal was obtained by solvent evaporation.The structure of the compound and its reaction intermediates were characterized by HMR,IR,Differential Scanning Calorimeter（DSC）and X-ray single crystal diffractometer.The results show that the compound belongs to the orthorhombic space group Pbca,with 8molecules in the unit cell（Z=8）,and has a crystal density of 1.836 g·cm^–3at 296 K.The Kamlet-Jacobs semi-empirical equation was used to calculate the explosion velocity of3,4-bis（（4-chloro-3,5-dinitro-1H-pyrazol-1-yl）methyl）-furoxan at 8304 m·s^-1and explosion pressure 30.5 GPa.The sensitivity was measured using the BAM standard method.The measured impact sensitivity was 9 J,and the friction sensitivity was 180 N.Bis（3-（4-chloro-3,5-dinitropyrazole-yl）methyl）-azo-1,2,4-oxadiazolewas synthesized using 4-chloropyrazole as raw material and its crystal was obtained by solvent evaporation.The structure of the compound and its reaction intermediates were characterized by HMR,IR,DSC and X-ray single crystal diffractometer.The results show that the compound belongs to the monoclinic space group P2₁/n,with 2 molecules in the unit cell（Z=2）,and has a crystal density of 1.828 g·cm^–3at 296 K.The Kamlet-Jacobs semi-empirical equation was used to calculate the detonation velocity of bis（3-（4-chloro-3,5-dinitropyrazole-yl）-methyl）-azo 1,2,4-oxadiazole 8028 m·s^-1and burst pressure of 28.6 GPa.The sensitivity was measured using the BAM standard method.The measured impact sensitivity was 10 J and the friction sensitivity was 180 N.Two high-energy insensitive compounds,（2-（（5-（Nitroamino）-1,3,4-oxadiazol-2 -yl）methyl）-2H-tetrazol-5-yl）nitroamide and（2-（（5-（trinitromethyl）-4H-1,2,4-triazol-3-yl）-methyl）-2H-tetrazol-5-yl）nitroamide were designed using 5-aminotetrazole as the reaction substrate,methylene group as a linking group to connect 5-aminotetrazole with1,2,4-triazole and 1,3,4-oxadiazole.The synthesis of the target compound was explored,and the existing products were characterized by HMR,IR,DSC and X-ray single crystal diffractometer.With the development goal of pursuing energetic compounds with high energy,insensitivity and excellent comprehensive performance,this article uses polynitropyrazole and 5-aminotetrazole as substrates,introduces other nitrogen heterocycles,increases energetic groups,designs and synthesizes them Several energetic compounds have been developed.The structure of the product and its reaction intermediates were characterized by nuclear magnetic resonance,Fourier infrared spectroscopy,thermal weight loss analyzer,differential scanning calorimeter,and X-ray single crystal diffractometer.The Kamlet-Jacobs semi-empirical equation was used to calculate the detonation velocity of the product and the sensitivity was determined by the BAM standard method.