In this study, transition-metal-free catalyzed [3+2] cycloadditions/oxidativearomatization three-component reactions for the successful direct construction of pyrrolo[3,4-a]indolizine-1,3(2H)-diones via pyridinium ylides are reported. This method utilizes readily available pyridines, acetophenones and maleimides as starting materials in the presence of TBAI (N-tetrabutylammonium iodide)/TBHP (tert-butyl
在这项研究中,无过渡金属催化的[3 + 2]环加成反应/氧化芳构化三组分反应可成功地通过吡啶鎓直接直接构建吡咯并[3,4- a ]吲哚嗪-1,3(2 H)-二酮。报道了叶立德。该方法在存在TBAI(N-四丁基碘化铵)/ TBHP(叔丁基氢过氧化物)的情况下,利用易于获得的吡啶,苯乙酮和马来酰亚胺作为起始原料,具有广泛的底物范围并且产率中等至良好,避免了使用金属催化剂和生成卤化物。
One-Pot Synthesis of Pyrrolo[3,4-<i>a</i>]indolizine-1,3-diones through [3+2] Cycloaddition-Oxidation Reaction Catalyzed by Cu<sup>II</sup>Salt and O<sub>2</sub>as the Oxidant
作者:Yun Liu、Hua-You Hu、Xian-Bin Su、Jin-Wei Sun、Chang-Sheng Cao、Yan-Hui Shi
DOI:10.1002/ejoc.201201488
日期:2013.4
An efficient one-pot synthesis of pyrrolo[3,4-a]indolizine-1,3-diones has been developed from maleimides, pyridines, and acyl bromides through a [3+2] cyclization–oxidation reaction catalyzed by CuII salt under O2 atmosphere. The advantage of this method is the use of molecular oxygen as the oxidant, in the presence of a catalytic amount of hydrated copper(II) chloride, to accomplish the reaction with