Alkali-Promoted Tandem Polymerization of Nucleophilic Acetylide Monomers and Aldehydes toward Luminescent Polymeric Materials

Alkyne-based polymerizations have been an invaluable tool for the preparation of functional polymers. In the reported polymerizations, alkynes generally function as electrophilic monomers. Theoretically, ethynyl groups of monomers could also be used as nucleophiles, and the polymerization using an ethynyl group as the nucleophile should be developed further. In this work, a potassium tert-butoxide (t-BuOK)-promoted tandem polymerization of aromatic diynes and commercially available benzaldehyde, in which ethynyl groups were used as nucleophiles, was successfully developed. Under optimized conditions, this polymerization could produce polymers with good solubility, well-defined structures, high-weight-averaged molecular weights (Mw, up to 76,000), and yields up to 93% in as short as 15 min at room temperature. Moreover, thanks to their ethynyl vinyl carbinol moieties, the resultant polymers show the interesting luminescent property, and some are aggregation-induced emission (AIE)-active. Thus, the nucleophilic alkyne-based cascade polymerization not only provides a powerful tool for the preparation of functional polymers but also might inspire innovation in the area of polymer chemistry.