Platinum(II)‐Crosslinked Single‐Chain Nanoparticles: An Approach towards Recyclable Homogeneous Catalysts

Abstract

We introduce the synthesis and in-depth characterization of platinum(II)-crosslinked single-chain nanoparticles (Pt -SCNPs) to demonstrate their application as a recyclable homogeneous catalyst. Specifically, a linear precursor copolymer of styrene and 4-(diphenylphosphino)styrene was synthesized via nitroxide-mediated polymerization. The triarylphosphine ligand moieties along the backbone allowed for the intramolecular crosslinking of single chains via the addition of [Pt(1,5-cyclooctadiene)Cl ] in dilute solution. The successful formation of well-defined Pt -SCNPs was evidenced by size exclusion chromatography, dynamic light scattering, nuclear magnetic resonance ( H, P{ H}, Pt), and diffusion-ordered spectroscopy. Finally, the activity of the Pt -SCNPs as homogeneous, yet recyclable catalyst was successfully demonstrated using the example of the amination of allyl alcohol.

Catalytically Active N‐Heterocyclic Carbene Release from Single‐Chain Nanoparticles Following a Thermolysis‐Driven Unfolding Strategy

“…Previous work in the area has typically focused on the formation of SCNPs by hydrogen or covalent bonding between supported orthogonal functions . More recently, coordination chemistry, where metals act as crosslinkers, inducing the single‐chain particle formation, has been developed . Surprisingly, the ability of Ag to trigger the single‐chain folding of catalytically active SCNPs remains unexploited despite the potential of Ag(I)‐NHC complexes to generate free NHCs and undergo transmetalation …”

Catalytic single-chain polymeric nanoparticles at work: from ensemble towards single-particle kinetics

“…Of particular interest are catalytically active SCPNs, which can be considered as a first step towards catalysts that show the activity and selectivity of natural enzymes. [7][8][9][10][11][12][13][14] Organometallic SCPNs, which are reminiscent of metallo-enzymes, have attracted significant attention in recent studies. SCPNs loaded with metal ions, such as those of palladium, 7,14 platinum, 8 ruthenium, 9 rhodium, 15 copper, [11][12][13] show efficient and selective catalysis in a variety of reactions.…”

“…[7][8][9][10][11][12][13][14] Organometallic SCPNs, which are reminiscent of metallo-enzymes, have attracted significant attention in recent studies. SCPNs loaded with metal ions, such as those of palladium, 7,14 platinum, 8 ruthenium, 9 rhodium, 15 copper, [11][12][13] show efficient and selective catalysis in a variety of reactions. For example, organocopper-based SCPNs were applied in catalyzing the oxidative coupling of terminal acetylenes, 11 hydroxylation of phenols, 12 and azide-alkyne cycloaddition, 13 in which the reaction media ranged from organic solvent to aqueous solution or even an intracellular environment.…”

Excellent Stability in Water of Single‐Chain Nanoparticles against Chain Scission by Sonication

“…A variety of highly efficient crosslinking chemistries have been applied to synthesize covalent‐bonded SCNPs such as the copper‐catalyzed azide–alkyne click chemistry, Glaser–Hay coupling, thiol‐ene/thiol‐yne coupling reactions, etc . Potential applications of these SCNPs include their use as additives for conventional thermoplastic materials to produce so‐called all‐polymer nanocomposites, and the development of stabilized supported catalysts, especially if the reactions are performed at relatively high temperature …”