5-甲基-6,7-二氢-5H-环戊并吡嗪的合成  

Synthesis of 5-methyl-6,7-dihydro-5H-cyclopentapyrazine

作　　者：杨翠平[1] 杨福斌[1] 康静静[1] 刘崇波[2] 温辉梁[1] 

机构地区：[1]南昌大学食品科学与技术国家重点实验室,南昌市南京东路235号330047 [2]南昌航空大学环境与化学工程学院,南昌市丰和南大道696号330063

出　　处：《烟草科技》2016年第2期42-46,共5页Tobacco Science & Technology

摘　　要：为改进5-甲基-6,7-二氢-5H-环戊并吡嗪(化合物2)的合成工艺条件,以甲基环戊烯醇酮和乙二胺为原料,无水乙醇作溶剂,二氧化锰作氧化剂,经缩合和氧化反应合成了化合物2,优化了合成条件,并采用1H NMR和IR技术对产物结构进行了表征。结果表明:当无水乙醇用量20 m L、n(甲基环戊烯醇酮)∶n(乙二胺)=1∶1.5(摩尔比)、60℃恒温反应2 h时,5-甲基-3,4,6,7-四氢-2H-环戊并吡嗪(化合物1)的收率达到95.7%;当n(氢氧化钾)∶n(二氧化锰)∶n(化合物1)=1∶2.4∶0.6、无水乙醇用量10 m L、80℃恒温反应15 h时,化合物2的收率为64.3%。Cyclopenapyrazine compounds have important sensory properties in food and tobacco smoke. With anhydrous ethanol as solvent, manganese dioxide as oxidant, 5-methyl-6,7-dihydro-5H-cyclopentapyrazine（Compound 2） was synthesized by methyl cyclopentenolone and ethylenediamine via condensation cyclization and oxidation. Moreover, the synthesis conditions were optimized, and the structures of the products were characterized by1 H NMR and IR. The results showed that the yield of 5-methyl-3,4,6,7-tetrahydro-2H-cyclopentapyrazine（Compound 1） was 95.7% under the optimized conditions of anhydrous ethanol 20 m L, n（methyl cyclopentenolone） ∶ n（ethylenediamine） =1 ∶ 1.5, reacting for 2 hours at a constant temperature of 60 ℃. When n（potassium hydroxide） ∶ n（manganese dioxide） ∶ n（Compound1） =1∶2.4∶0.6 and the amount of anhydrous ethanol was 10 m L, the yield of Compound 2 reached 64.3% after reacting for 15 hours at 80 ℃.

关 键 词：5-甲基-6 7-二氢-5H-环戊并吡嗪 甲基环戊烯醇酮 缩合环化 氧化 

分 类 号：TQ651.1[化学工程—精细化工]