Improvement Of The Synthesis Process Of 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide

The new synthesis process of the insensitive high energy explosive 2,6-diamino-3,5-din itropyrazine-1-oxide(LLM-105)was investigated.LLM-105 is a new explosive with high density,moderate energy and good stability.LLM-105 was synthesized by three-steps reactions of nitrosylation,cyclization,and nitrifycation,using iminodiacetonitrile as starting material.The total yield of LLM-105 was 44%.The new synthesis process had the advantage of simple synthetic operation,low cost of synthesis and less environment pollution.Nitrosylation of iminodiacetonitrile to N-nitrosobis(cyanomethyl)amine.The best condi-tions:Added sodium nitrite to iminodiacetonitrile in aqueous solution,and stirred until disso-lved,the initial temperature was 0-5℃,1M sulfuric acid aqueous solution was dropwised;the mole ratio of iminodiacetonitrile,sodium nitrite and sulfuric acid was 1:1.2:0.5,then,the reaction temperature was 20℃,the reaction time was 2h.After completion of reaction,the re-action mixture was extracted with ethyl acetate,anhydrous sodium sulfate drying,steaming,and drying.The yield was 91.5%.(2)cyclization of N-nitrosobis(cyanomethyl)amine to 2,6-diaminopyrazin-1-oxide(DAPO).The solvent was methanol,and the catalyst was sodium hydroxide.The best conditions:ONN(CH2CN)2:NH2OH·HC1:NaOH=1.0:0.6:1.0(mass radio),the initial temperature was 5～10℃,the reaction time was 30min,then,the reaction temperature was 20℃,the reaction time was 2h.The yield was 78.7%.(3)Nitrification of 2,6-diaminopyrazine-l-oxide(DAPO)to 2,6-diamino-3,5-dinitropyrazine-1-oxide(LLM-105).The nitrating agent was fuming nitric acid,the solvent was 20%fuming sulfuric acid.The best conditions:the mass volume ratio of 2,6-diaminopyrazine and fuming nitric acid was 0.5g/mL,control the temperature 15℃,0.5h,and then,rose the temperature to 25 ℃,5h.The yield was 60%.The study tried to make the first two steps together,tried to get intermediates by filtering to remove inorganic salt,then the mixture cyclized with hydroxylamine hydrochloride to syn-thesis 2,6-diaminopyrazine-1-oxide(DAPO),the yield was 85.7%.In addition,this study also discussed the new synthetic route of LLM-105,designed a new synthetic route of LLM-105.