Sequential Hydration-Condensation-Double Cyclization of Pyridine-Substituted 2-Alkynylanilines: An Efficient Approach to Quinoline-Based Heterocycles
作者:Ke Ding、Qiang Zhu、Lijie Peng、Honggen Wang、Changlan Peng
DOI:10.1055/s-0030-1260001
日期:2011.6
An environmentally benign and atom-economical process to construct a unique quinoline-based tetracyclic scaffold, through sequential hydration-condensation-double cyclization reactions, has been described. The reaction starts with readily available pyridine-substituted o-alkynylanilines and β-keto esters, promoted by p-toluenesulfonic acid in ethanol in one pot. In the absence of β-keto esters, multisubstituted quinolines are formed bimolecularly in reasonable yields.
描述了一种环境友好且原子经济的方法,通过顺序水合-缩合-双环化反应构建独特的基于喹啉的四环支架。该反应从容易获得的吡啶取代的邻炔基苯胺和β-酮酯开始,通过一锅中的乙醇中的对甲苯磺酸促进。在没有β-酮酯的情况下,多取代喹啉以双分子形式以合理的产率形成。