Bimetallic nano-Pd/PdO/Cu system as a highly effective catalyst for the Sonogashira reaction

A copper-supported nanopalladium catalyst obtained by an innovative method of nanoparticle transfer from the intermediate carrier SiO2 to the target Cu carrier was a highly efficient and selective catalyst, giving as much as quantitative conversion and yield in a series of Sonogashira reactions. Comparisons with other Pd systems, especially Pd/SiO2, indicated substantial advantages for this novel catalytic system. X-ray photoelectron spectroscopy (XPS) studies of the prepared Pd/Cu catalyst revealed the development of a PdO species in the Pd/Cu system and illustrated for the first time the importance of the resulting Pd/PdO/Cu system for efficient Sonogashira coupling.