Host-enhanced π-π interaction for water-soluble supramolecular polymerization.

Host-enhanced π-π interaction based on anthracene derivatives and cucurbit[8]uril can be used as the driving force for constructing water-soluble supramolecular polymers. For this purpose, two anthracene moieties were encapsulated into one cucurbit[8]uril cavity, forming a ternary complex. After encapsulation in the host, the distance between the two anthracene moieties was shortened, and the π-π interaction between them was enhanced significantly. To realize supramolecular polymerization, a bifunctional monomer consisting of two anthracene moieties and a short linker in between was carefully designed. Cyclization was avoided in this way. Thus, host-enhanced π-π interaction can function as a new driving force for supramolecular polymerization.