New Polysilyl Dendritic Precursors of Triazolylferrocenyl and Triazolylcobalticenium Dendrimers—Comparative Electrochemical Study and Stabilization of Small, Catalytically Active Pd Nanoparticles

摘要: The 27-ferrocenyl-terminated and the 27-cobalticenium-terminated metallodendrimers 5 6, respectively, were synthesized using only hydrosilylation reactions click methodology. These new characterized by 1H 13C NMR, infrared, mass spectroscopy, elemental analysis, cyclic voltammetry. dendrimers being isostructural in their neutral forms, show same intensities for redox exchange between cationic corresponding approximately to transfer of 27 electrons, as deduced from Bard–Anson equation. metallodendrimer was used form dendrimer-encapsulated palladium nanoparticles (PdDENs). TEM images indeed that PdDENs are very small (average diameter = 1.0 nm) relatively monodisperse. Their catalytic activity evaluated Suzuki–Miyaura C–C coupling with various substituted aryl bromides (0.2 mol% Pd per mole substrate used). This is lower than previously studied ...