Modified palladium-catalyzed regioselective ortho-arylation of sp2 C–H bond substrates with a low catalyst loading
作者:Fan Yang、Yangjie Wu、Yanan Li、Biao Wang、Junli Zhang
DOI:10.1016/j.tet.2008.11.001
日期:2009.1
substrates such as arylated benzoxazoles, acylated anilines, and pyridines has been developed. The arylation was performed in trifluoroacetic acid (TFA) under air by using PdCl2 as the catalyst with a low catalyst loading of 1 mol %. And it was found for the first time that the addition of weak base K3PO4 to the acidic solvent could remarkably enhance the reaction rate. The arylated products were isolated
一种用于新颖的和普遍适用的系统邻广泛菌属的-arylation 2 C-H键的基材如苯并恶唑芳基化,酰化苯胺,和吡啶已经研制成功。通过使用PdCl 2作为催化剂,以1mol%的低催化剂负载,在空气中在三氟乙酸(TFA)中进行芳基化。并且首次发现向酸性溶剂中添加弱碱K 3 PO 4可以显着提高反应速率。对于含间位取代基的底物,芳基化产物以中等至良好的产率分离,具有高的区域选择性。该芳基化耐受各种官能团,例如CH 3,CH 3 O,CH 3 CO,Br和Cl。