Single-Chain Self-Folding of Synthetic Polymers Induced by Metal-Ligand Complexation

The controlled folding of a single polymer chain is for the first time realized by metal-complexation. alpha,omega-Bromine functional linear polymers are prepared via activators regenerated by electron transfer (ARGET) ATRP ((M) over bar (n, SEC) = 5900 g mol(-1), D = 1.07 and 12 000 g mol(-1), D = 1.06) and the end groups of the polymers are subsequently converted to azide functionalities. A copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction is carried out in the presence of a novel triphenylphosphine ligand and the polymers to afford homotelechelic bis-triphenylphosphine polymeric-macroligands (MLs) ((M) over bar (n, SEC) = 6600 g mol(-1), D = 1.07, and 12 800 g mol(-1), D = 1.06). Single-chain metal complexes (SCMCs) are formed in the presence of Pd(II) ions in highly diluted solution at ambient temperature. The results derived via H-1 and P-31{H-1} NMR experiments, SEC, and DLS unambiguously evidence the efficient formation of SCMCs via metal ligand complexation.