The synthesis and applications of porphyrin-containing pillararenes

Porphyrin-pillararene hybrid compounds/systems have attracted much more attention due to the synergistic effect generated by combining two significant macrocycles together in supramolecular chemistry. On the one side, porphyrin units can serve as the N-donor to coordinate with metal cations, acting as a good supplement to the supramolecular recognition abilities of pillararene cavities. On the other side, pillararenes can be grafted to bunches of various functional groups by efficient and easy modification procedures in order to improve the water-solubility of porphyrins for different applications, such as in biomedicine, as well as to enrich the family of porphyrin-based supramolecular architectures. Diverse bonds and interactions have been employed in the fabrication of porphyrin-pillararene hybrid compounds/systems, including covalent bonds and noncovalent interactions, as well as mechanical bonds. Thus, the obtained porphyrin-pillararene hybrid compound, supramolecular self-assembly, and mechanically interlocked molecules have wide applications, e.g., as hetero-ditopic receptors, in detection and sensing, as building blocks for advanced self-assembled materials, in drug delivery and release systems, in photodynamic therapies, and in light-harvesting devices.