• Trouillet, Vanessa
• Roesky, Peter
• Willenbacher, Johannes
• Knoefel, Nicolai
• Altintas, Ozcan
• Monteiro, Michael

Abstract

We report the facile synthesis of well-defined palladium(ii) cross-linked single-chain nanoparticles (Pd-SCNPs) using the 'repeating unit approach'. The linear precursor polymer (M<inf>n</inf> ≈ 10200 g mol-1, ≈ 1.17) was synthesized via nitroxide mediated statistical copolymerization of styrene and 4-(chloromethyl)styrene (CMS) followed by a post-polymerization modification of the resulting copolymer to covalently attach the triarylphosphine ligand moieties. The ligand content along the lateral polymer chain was 12%. Intramolecular crosslinking was performed in diluted solution with a suitable precursor complex (Pd[1,5-cyclooctadiene]Cl<inf>2</inf>) to afford the well-defined Pd-SCNPs, which feature a hydrodynamic diameter of D<inf>h</inf> = 5.4 nm. The palladium(ii) containing single-chain nanoparticles were characterized in-depth using 1H NMR spectroscopy, 31P{1H} NMR spectroscopy, dynamic light scattering (DLS), size exclusion chromatography (SEC), 1H spin-spin relaxation time (T<inf>2</inf>) analysis, X-ray photoelectron spectroscopy (XPS), and log-normal distribution (LND) simulations. Finally, the applicability of the Pd-SCNPs as catalyst in the Sonogashira coupling was exemplified. © The Royal Society of Chemistry 2015.

Topics

• nanoparticle
• x-ray photoelectron spectroscopy
• simulation
• copolymer
• size-exclusion chromatography
• Nuclear Magnetic Resonance spectroscopy
• dynamic light scattering
• palladium
• post-polymerization modification