Heterobimetallic Au(I)/Y(III) single chain nanoparticles as recyclable homogenous catalysts

Heterobimetallic single chain nanoparticles were synthesized and applied as recyclable homogenous catalysts. A terpolymer containing two orthogonal ligand moieties, phosphines and carboxylates, was obtained via nitroxide-mediated polymerization. Single chain nanoparticle (SCNP) formation is induced by selective metal complexation of Y(III) by the carboxylate functions, while Au(I) is selectively coordinated to phosphine moieties. In contrast to previous work, the two functionalities, SCNP folding and formation of a catalytic center, were distributed over two metals, which critically increases the flexibility of the system. The formation of Au(I)/Y(III)-SCNPs is evidenced by size exclusion chromatography, dynamic light scattering, nuclear magnetic resonance (1H, 31P{1H}) and infrared spectroscopy. Importantly, the activity of the Au(I)/Y(III)-SCNPs as homogenous, yet recyclable catalyst, bridging the gap between homogenous and heterogeneous catalysis, was demonstrated using the hydroamination of aminoalkynes as an example.