Pd Nanoclusters in CC Coupling Reactions: Proof of Leaching

A simple experiment based on exclusion of Pd nanoclusters was used to identify the true catalytic species in cluster-catalyzed Heck cross-couplings. A special reactor was used in which two compartments are separated by a nanoporous membrane that allows the passage of Pd atoms and ions but not of Pd nanoclusters (see picture). The results show that the real catalysts in the Heck coupling of n-butyl acrylate with iodobenzene are species leached from the Pd nanoclusters.