Research On The Synthesis Of 2-Cyanopyrazine

The uses of pyrazine derivatives in pharmaceutical products, agricultural chemicals and spices were introduced in this thesis. The research situation, market foreground and research purpose of the goal product cyanopyrazine were discussed. We also summarized the methods of sythesis of cyanopyrazine and 2-methylpyrazine.First, ethylenediamine and 1,2-dihydroxypropane were chosen as raw materials to prepare 2-methylpyrazine with the method of catalytic action. The catalyst was KB-207 made by Sichuan Lianya, which compounds CuO 41.26%, ZnO 41.79%, Al2O3 7.75%. The reaction was preceded in fixed bed catalytic reactor. The effects of temperature, ratio of feeds, the carrier gas's use level on the yield were studied. The experiments showed, when the temperature was about 380 , catalyst was not activated, 40% water was used in the feed fluid, the high rate of conversion and yield can be get. The highest yield is 68%. Then ammoxidation catalytic synthesis of cyanopyrazine was studied with the raw material 2-methylpyrazine. We studied the process conditions with use of three kinds of catalysts made by ourselves. The yield can get more than 40% when use the catalyst MoxPyOzXY. The best process condition is temperature 370 , 2-methylpyrazine: ammonia: oxygen= 1:2.5-3:6 (mole ratio). When Sb2O3-V2O5-TiO2/SiO2 catalyst was used, the yield can be 55%, the selectivity is more than 70%. When the temperature was 380 , 2-methylpyrazine: ammonia: oxygen= 1:3 -6:8.5 (mole ratio). The experiments on stability of the catalyst were also done and the result shows that this catalyst is stable.