Pyridine-functionalized luminescent organoboron quinolate block copolymers as versatile building blocks for assembled nanostructures

Novel luminescent boron quinolate block copolymers with pyridine functionalities were prepared via RAFT polymerization and employed as building blocks for assembled nanostructures. In selective solvents, the block copolymers self-assembled into vesicles, spherical and extended branched aggregates. Quaternization reactions were performed to modify the solubility of the block copolymers and to prepare a cross-linked polymeric gel. As polymeric Lewis bases, the pyridine-functionalized block copolymers are able to form supramolecular complexes with metal ions and Lewis acids. Coordination to ZnCl₂ in chloroform led to spherical micelles or larger aggregates. The supramolecular coassembly of PS-b-PBQPy-1 and zinc meso-tetraphenylporphyrin (ZnTPP) in cyclohexane as a selective solvent for PS resulted in extended branched structures with controllable emission properties. Energy transfer from the boron chromophores to the ZnTPP moieties was observed in these supramolecular complexes.