Palladium-catalyzed direct ortho-alkynylation of aryl acetamides with low catalyst loading

The palladium-catalyzed alkynylation of phenylacetic acid derivatives using 4-CF₃C₆F₄NH₂ as the auxiliary is described. The reaction efficiency can be greatly promoted by pyridine ligand, which enables the reaction to proceed at a catalyst loading as low as 1 mol%. Various functional groups are tolerated under the reaction conditions. The kinetic studies show that the rate of the reaction is first order in phenylacetamide and the Pd(OAc)₂ in combination of the pyridine ligand provides a highly robust and effective catalyst.