Construction of Polypseudorotaxane from Low-Molecular Weight Monomers via Dual Noncovalent Interactions

The design and construction of polypseudorotaxanes via noncovalent interactions from low-molecular weight monomers (LMWMs) is playing an important role in the field of supramolecular polymers. In this work, we synthesized three low-molecular weight compounds for supramolecular polymerizations and attempted to employ the metal ligand interaction between the pyridine nitrogen and Pd (II), for cooperating with the host guest binding between azobenzene and beta-cyclodextrin (beta-CD), to complete the end-to-end connection of the polymer chains. Routes for stepwise introduction of two of the self-assembly behaviors as well as a one-pot preparation were investigated by H-1 NMR and 2D nuclear Overhauser enhancement spectroscopy (NOESY) H-1 NMR spectroscopy. The self-assembly strategies based on the full orthogonality of both noncovalent interactions will allow for a smart and rapid synthesis of precise structural controlled supramolecular polymeric assemblies.