Phosphine-free palladium-catalysed direct 5-arylation of imidazole derivatives at low catalyst loading
作者:Julien Roger、Henri Doucet
DOI:10.1016/j.tet.2009.09.084
日期:2009.11
The regioselective 5-arylation of imidazole derivatives with aryl bromides using a low loading of a phosphine-free palladium catalyst gives a simple and economic access to the corresponding 5-arylimidazoles. The choice of the base and of the solvent was found to be crucial to form these products in high yields. Using KOAc as the base, DMAc as the solvent and only 0.5–0.01 mol % Pd(OAc)2 as the catalyst