Palladium-catalyzed regiocontrolled internal heteroarylation of electron-rich olefins with heteroaryl halides
作者:Dan Xu、Zhihua Liu、Weijun Tang、Lijin Xu、Zeynab Hyder、Jianliang Xiao
DOI:10.1016/j.tetlet.2008.08.005
日期:2008.10
A highly efficient palladium-catalyzed Heck coupling reaction of heteroaryl halides with electron-rich vinyl ether and hydroxyalkyl vinyl ethers is described. It was found that the choice of solvent, ligand, and reaction temperature had a fundamental influence on the regioselectivity and reactivity of the reaction, and the combination of Pd(OAc)2 and DPPF in ethylene glycol led to the most effective
描述了杂芳基卤化物与富电子乙烯基醚和羟烷基乙烯基醚的高效钯催化的Heck偶联反应。发现溶剂,配体和反应温度的选择对反应的区域选择性和反应性具有根本影响,并且Pd(OAc)2和DPPF在乙二醇中的组合导致最有效的催化体系。在这些条件下,各种杂芳基卤化物与富电子烯烃非常快速地反应,从而以良好或优异的收率独家提供支链产物,而无需使用三氟甲酸酯,卤化物清除剂或离子液体。