Chalcogen-Bonding Supramolecular Polymers.

Exploring unknown supramolecular interacting forces to create novel supramolecular materials is an eternal theme of supramolecular science. Here, we first report a new family of supramolecular polymers formed by unconventional chalcogen-bonding interactions. A class of chalcogen-containing macrocyclic receptors, termed as chalcogena[4]arene (ChA[4], Ch = Te and Se), are designed as chalcogen-bonding donors. Using homoditopic ChA[4]s as monomers, they can linearly polymerize with a twin-headed N-oxide dianion surfactant to organize into noncovalent polymer arrays via end-to-end Ch···O- chalcogen-chalcogen complexation in aqueous media and further self-assemble into supramolecular hydrogel fibers. The binding chemistries of different chalcogen bonds play a decisive role in tuning the parameters of noncovalent polymerizations and the mechanical properties of hydrogel networks. Moreover, such chalcogen-bonding-mediated polymer arrays can be reversibly disconnected by competing anions. This study would inspire a new direction inquiry of unorthodox supramolecular interactions and their related supramolecular materials.