An investigation into the electrophilic cyclisation of N-acyl-pyrrolidinium ions: a facile synthesis of pyrrolo-tetrahydroisoquinolones and pyrrolo-benzazepinones
作者:Frank D. King、Abil E. Aliev、Stephen Caddick、Royston C. B. Copley
DOI:10.1039/b907400g
日期:——
N-arylethyl-acylpyrrolidinium ions gave moderate to good yields of pyrrolo-tetrahydroisoquinolones and pyrrolo-benzazepinones respectively. Electron-donating R substituents enhanced the rate of reaction and gave higher yields than electron-withdrawing substituents. Substituents on the methyl or ethyl chain in general enhanced the reaction, unless sterically encumbered. The equivalent acylpiperidinium ions cyclised much
三氟甲磺酸介导的N-芳基甲基-和N-芳基乙基-酰基吡咯烷鎓离子的环化分别给出了中等至良好的吡咯并四氢异喹啉酮和吡咯并苯并b庚酮的产率。供电子的R取代基比吸电子的取代基提高了反应速率并提供了更高的产率。除非空间上阻碍,否则甲基或乙基链上的取代基通常会增强反应。等效的酰基哌啶鎓离子环化的速度慢得多,产率也低。