一种结构新颖的中氮茚衍生物的合成新方法

A New and Efficient Methodology for the Synthesis of Novel Indolizine Derivatives

以吡啶作为碱和反应底物,利用其与溴代苯乙酮和叠氮基肉桂酸酯的三组分串联反应发展了一种合成结构新颖的1,2,3-三取代中氮茚衍生物的新方法。利用溴代苯乙酮与吡啶形成的氮叶立德作为亲核试剂和1,3-偶极子前体,经由1,3-偶极环加成反应构建中氮茚骨架。各种叠氮基肉桂酸烷基酯和苄基酯均能很好的适用于该反应,产率为54%~79%,吡啶上连有取代基时该反应不能发生,所有产物结构均经^(1)H NMR,^(13)C NMR和HR-MS表征。最后根据实验结果提出了一种可能的反应机理。

A novel and efficient base-promoted three-component reactions of pyridine with azido cinnamic esters and 2-bromoacetophenones for the synthesis of novel 1,2,3-trisubstituted indolizine derivatives in good to high yields has been developed.Construction of indolizine skeleton via 1,3-dipolar cycloaddition using pyridine and 2-bromoacetophenones derived N-ylides as nucleophiles and 1,3-dipole precursors.Various alkyl and benzyl azido cinnamic esters were applied to this reaction well and generated the corresponding indolizine derivatives in 54%-79%yields.The structures of all compounds were characterized by ^(1)H NMR,^(13)C NMR and HR-MS.A proposed mechanism was described.