Fluorescent and Catalytically Active Single Chain Nanoparticles

Fluorescent and catalytically active single chain nanoparticle (SCNP) systems allow for the visualization and tracing of the catalyst's distribution in a reaction system. We herein report a synthetic strategy to such SCNPs, generated through a photoactivated reaction at visible light (λmax= 415 nm) irradiation. Notably, the compaction reaction generates a fluorescent entity via a pro-fluorescent precursor. A polymer backbone (Mn= 21,000 g mol-1and D = 1.3), carrying phosphine ligands for the coordination of catalytically active gold complexes and the photoreactive ortho-methylbenzaldehyde units and complementary alkyne moieties, was constructed based on nitroxide-mediated polymerization. The synthetic protocol entails an intermediate protection sequence for the catalyst-carrying phosphine unit to enable the installation of the cross-linking entities. The successful compaction of the SCNPs is demonstrated by a reduction in the chain's hydrodynamic volume via size exclusion chromatography and diffusion-ordered NMR spectroscopy.