Study on the Nitration Reaction of 2,6-Diacetamidopyrazine-1-Oxide

Nitration reactions of 2,6-diacetamidopyrazine-1-oxide in mix acid or fuming nitric acid/acidic ionic liquid were researched.In the mixed acid nitration system,effects of mixed acid nitration agent types on the yield and purity of the product LLM-105 were investigated.In the fuming nitric acid and N,N,N-trimethyl-N-propanesulfonic acid ammonium hydrogen sulfate(TMPSHSO4) nitration system,the effects of acidic ionic liquid quantity,nitration temperature and acidic ionic liquid recycle times on the yield and purity of LLM-105 were investigated in the catalyst condition of acidic ionic liquid.The results show that,in the mixed acid nitration system,the best nitrating agent of 2,6-diacetamidopyrazine-1-oxide are KNO3 and 20% oleum,the product yield is 72.5%,and the purity is 98.6%.In the fuming nitric acid and TMPSHSO4 nitration system,optimal reaction conditions are that molar ratio of TMPSHSO4 and 2,6-diacetamidopyrazine-1-oxide is 0.051.00,reaction temperature is 75 ℃,the product yield is 64.8%,the purity is 98.5%,and TMPSHSO4 could be recovered and used repeatedly for three times.Nitration of 2,6-diacetamidopyrazine-1-oxide by fuming nitric acid and TMPSHSO4 has more advantages.The structure of LLM-105 was also characterized by1 H NMR,IR and MS.