Assembly of a Self-Complementary Monomer: Formation of Supramolecular Polymer Networks and Responsive Gels

Self‐complementary monomer 1, which combines a macrotricyclic polyether and two dibenzylammonium ions together, was synthesized, and its self‐assembly into supramolecular polymer networks by host–guest interactions was studied. For the purpose of comparative study, two model molecules 2 and 3 were also prepared. It was found that model molecule 2 and dibenzylammonium ion 4 form a 1:2 complex in solution and in the solid state, which afforded a model system for the investigation of the assembly behavior of monomer 1. Consequently, the 1H NMR spectrum of 1 in CD3CN showed characteristic proton signals similar to the model system, which suggested that 1 self‐assembles into a supramolecular polymer network. Formation of the supramolecular polymer was further evidenced by the MALDI‐TOF MS spectrum, viscometry, and dynamic light‐scattering (DLS) experiments. Moreover, it was found that the decomposition and re‐formation of the supramolecular polymer could be chemically controlled by the use of triethylamine and trifluoroacetic acid. Interestingly, the supramolecular polymer forms an organogel both in CD3CN and in 1:1 (v/v) CDCl3/CD3CN, and reversible thermo‐ and pH‐induced gel–sol transitions were also found. The presented work will provide a new strategy for the construction of supramolecular polymers with specific structures and properties. A sense of self: A self‐complementary monomer that contained a macrotricyclic polyether and two dibenzylammonium moieties was found to assemble into chemically controlled supramolecular polymer networks (see figure) by intermolecular host–guest interactions. The polymer also showed gel properties.