Novel Synthesis of 2-Alkylquinolizinium-1-olates and Their 1,3-Dipolar Cycloaddition Reactions with Acetylenes
作者:Andreas Gebert、Max Barth、Anthony Linden、Ulrich Widmer、Heinz Heimgartner
DOI:10.1002/hlca.201200038
日期:2012.5
derivatives have the potential to undergo cycloaddition reactions with double and triple bonds, e.g., 1,3‐dipolar cycloadditions or DielsAlder reactions. We here report on the scope and limitations of cycloaddition reactions of 2‐alkylquinolizinium‐1‐olates 9 with electron‐poor acetylene derivatives. As main products of the reaction, 5‐oxopyrrolo[2,1,5‐de]quinolizines (=‘[2.3.3]cyclazin‐5‐ones’) 19 were
几个2- alkylquinolizinium -1- olates 9,即,heterobetaines,从酮制备11,后者具有容易得到的或者从吡啶-2-甲醛经由一个格利雅反应,然后进行氧化反应用的MnO 2,或从2-吡啶甲酸(=吡啶-2-羧酸)通过相应的Weinreb酰胺和随后的格利雅(Grignard)反应进行。介离子heterobetaines如quinolizinium衍生物必须经历与双键和三键,环加成反应的可能性例如,1,3-偶极环加成或狄尔斯阿尔德反应。我们在这里报告了2-烷基喹啉鎓-1-油酸酯9与贫电子乙炔衍生物的环加成反应的范围和局限性。作为反应的主要产物,通过区域选择性的[2 + 3]环加成反应和环己二烯酮形成了5-氧代吡咯并[2,1,5- de ]喹啉(= [[2.3.3] cyclazin-5-ones])19衍生物,形成经由一狄尔斯阿尔德反应,被作为副产物获得。2-