Study On The Synthesis Of1-Methyl-3,4,5-trinitropyrazole

Nitropyrazole compounds have attracted increasing attention in the field of energeticmaterials in recent years for the characteristics of high density, high energy and lowsensitivity. Overseas research shows that1-methyl-3,4,5-trinitropyrazol, an insensitiveexplosive with low melting energy, whose explosive properties are similar to RDX and whosesensitivity is close to B explosive, is one of such nitropyrazole derivatives. Therefore,1-methyl-3,4,5-trinitropyrazole is a potential energetic material. However, its synthesis hasnot been studied in depth at home so far. Thus, this research is of great significance.Firstly, the exploration of nitropyrazole direct nitration synthesis is based on the rawmaterial N-methylpyrazole and three different nitrating agents. Meanwhile, HPLC, IR,1HNMR,13CNMR, elemental analysis and DSC thermal analysis are used to characterize thereaction product. It proves that the main product obtained is1-methyl-4-nitropyrazole underlow temperature conditions and that the main product obtained is1-methyl-3,4-dinitropyrazole under high temperature conditions. It is mentioning that1-methyl-3,4,5-three nitropyrazole is not found in the synthesis of the product.Secondly, under the interaction of the raw material N-methylpyrazole and theiodine/iodide as the iodide agent, sulfur nitrate mixed acid as nitrating agent,1-methyl-3,4,5-trinitropyrazole is producted, which is further used to nitrify the targetproduct1-methyl-3,4,5-triiodopyrazole under the influence of sulfur-nitrate mixed acid. Thereaction products which are iodinated and nitrified are characterized and analyzed themechanism of iodide and nitrification with the methods of HPLC, IR,1HNMR and MS etc.The iodide process is also optimized. An optional production condition is obtained: reactionat80℃, reaction time2.5h, the ratio of n(I2) and n(C4H6N2)=6:5, the yield95%. In theprocess nitrification,5-iodo-l-methyl-3,4-dinitropyrazole is finally obtained through farthernitration to the intermediate product1-methyl-3,4,5-trinitropyrazole.Finally, after the process of nitration, rearrangement, further nitration and methylation 1-methyl-3,4,5-trinitropyrazole is finally synthetized by the raw material3-nitropyrazole.Additionally, the intermediate product is characterized through TLC, IR and1HNMR.Moreover,3,5-dinitropyrazole is also optimized. The optional rearrangement conditions areas follows: glycol is a solvent rearrangement and rearranging temperature at197℃. The lowyield of3,4,5-trinitropyrazole potassium salt is analyzed as well.When compared with various synthetic processes, the route of using3-nitropyrazole asraw material to synthetize1-methyl-3,4,5-trinitropyrazole is the most promising method andis suitable for industrial applications.In this thesis,the predicted multinitropyrazole derivatives by B-W rules, the velocity ofdetonation and the C-J evaluated by Rothsteine’s method and Cooper method are applied tofurther confirm1-methyl-3,4,5-trinitropyrazole as potential energetic materials.Study on the synthesis of1-methyl-3,4,5-trinitropyrazole lays a foundation for thenitropyrazole substances industrial production.