Regioselective Synthesis of Substituted Triazolium Salts via 1,3-Dipolar Cycloaddition Reactions
作者:Atef M. Amer
DOI:10.1007/s00706-003-0041-1
日期:2003.12.1
The regioselectivity of 1,3-dipolar cycloaddition reactions of 1-aza-2-azoniaallene salts with α,β-unsaturated nitriles such as acrylonitrile or cyclohexylidene acetonitrile afforded only 1,2,4-triazolium salts via addition to the nitrile group, while the other expected pyrazolium salts were not observed. Moreover, 1-aza-2-azonia-allene salts reacted with other competitive systems such as α-iminonitrile
的与α,β不饱和腈如丙烯腈或亚环己基-1-氮杂-2- azoniaallene盐1,3-偶极环加成反应区域选择性乙腈,得到仅-1,2,4-三唑盐 经由 除腈基,而未观察到其他预期的吡唑鎓盐。此外,1-氮杂-2-氮杂苯丙氨酸盐与其他竞争性系统(如α-亚甲基腈衍生物)反应,仅 通过 生成三唑盐 除了腈而不是亚氨基。用3-吡啶腈处理异丙苯得到吡啶鎓盐。然而,可以由异丙苯和2,6-二甲氧基苄腈制备2,3-二甲基-5-(2,6-二甲氧基苯基)-[1,2,4]三唑。讨论了腈与由1,2,3-茚满三酮和9-乙酰菲制得的1-氮杂-2-氮杂-丙二烯盐的一些反应。