Au–Pd Bimetallic Catalysis: The Importance of Anionic Ligands in Catalyst Speciation

Synergistic gold–palladium catalytic processes have been intensively sought during the past decade, because the combination of the carbophilic Lewis acidity of Au with the redox properties of Pd within a catalytic cycle is particularly appealing for the synthesis of novel functionalized compounds. We demonstrate here the feasibility of a Au–Pd bimetallic catalytic system based on the generation of competent Au and Pd species by anionic ligand exchange. This strategy enabled the preparation of a variety of substituted butenolides in a simple and efficient way.