Characterization of a Poly-4-Vinylpyridine-Supported CuPd Bimetallic Catalyst for Sonogashira Coupling Reactions

CuPd bimetallic solvated metal atoms (SMA) synthesized by metal vapor synthesis (MVS) technique and supported on poly-4-vinylpyridine (PVPy) resin, showed significantly higher catalytic activity in Sonogashira-type carbon-carbon coupling reactions than the corresponding monometallic Cu and Pd systems as well as their physical mixture. The analysis of the bimetallic catalyst combining transmission electron microscopy techniques and X-ray absorption fine structure (XAFS) spectroscopy revealed the presence of small Pd nanoparticles (d(m) = 2.5 nm) while the analysis of the X-ray absorption data, at the Cu Kedge suggests the formation of thin and incomplete Cu oxide layers around the Pd-rich cores.