5-烃基-2,3-二甲基吡嗪N-单氧化物的合成  

Synthesis of 5-Alkyl-2,3-Dimethylpyrazine-mono-N-Oxides

作　　者：蔡松传[1] 赵焘南[1] 孙德华[1] 张道信 包燕雏 

机构地区：[1]南京大学化学系,南京210008

出　　处：《高等学校化学学报》1992年第1期70-72,共3页Chemical Journal of Chinese Universities

摘　　要：一烃基或二烃基吡嗪的N-单氧化物可以进行氯化、乙酰氧基化等反应,它是重要的有机合成中间体.据报道二烃基吡嗪与30％过氧化氢在醋酸中进行N-氧化反应,当二烃基吡嗪:30％过氧化氢:醋酸的摩尔比为1:2:5、反应温度70～80℃、反应时间8h时,产物是N-单氧化物;当摩尔比为1:4:10、反应温度95℃、反应时间8～24h时。N-oxidation of 5-alkyl-2, 3-dimethylpyrazines with 30% H2O2-AcOH usually gives 1-N-oxides, 4-N-oxides and 1,4-N-dioxides. When the molar ratio of pyrazines/H2O2/AcOH is 1 : 1. 2 : 15 at 70℃ , the reaction is gives mono-N-oxides with best yields. N-oxidation of ten 5-alkyl-2,3-dimethylpyrazines were carried out under the above conditions, giving thirteen new compounds 5-alkyl-2,3-dimethylpyrazine-mono-N--oxid.es with satisfactory yields (50% - 70%). Their structures were confirmed by elemental analysis, IR,1H NMR and MS spectrometry. The structures of 1-N-oxides and 4-N-oxides were determined on the basis of 1H NMR spectral data, since the N-oxide group in substituted pyrazine mono-N-oxides gives the anisotropic effect. Additionally, the structures of eight new 1,4-N-dioxides obtained were confirmed by elemental analysis, IR and 1H NMR spectrometry.

关 键 词：吡嗪 N-氧化反应 N-单氧化物 合成 

分 类 号：O626.415[理学—有机化学]