Multicomponent Spiropolymerization of Diisocyanides, Activated Alkynes, and Bis-Anhydrides

Among various polymerization reactions, multicomponent spiropolymerization (MCSP) based on diisocyanides, activated alkynes, and a third monomer is an important tool for the in situ synthesis of multifunctional spiropolymers. In this work, a new MCSP based on the selection of bis-anhydrides as a third monomer was successfully developed under mild conditions. The obtained spiropolymers have high molecular weights (M_wup to 92,600 g/mol) and yields (up to 92%), as well as good solubilities and thermal stabilities. The benzophenone-containing spiropolymer P1a3e with aggregation-induced emission characteristics exhibits good UV-irradiation degradation performance, making it potentially applicable as a photoresist material component. Moreover, the spiropolymer P1a3f containing the acid-sensitive iminofuran ring is able to be degraded by a strong acid, while its postmodified product P1a3f-SH has higher degradation efficiency because of the enhanced water solubility. The results reveal that both P1a3f and P1a3f-SH with low cytotoxicities could potentially be used as acid-promoted release carriers of drugs for the protection of gastric mucosa. Therefore, this reaction enriches the family of MCSP reactions for preparing multifunctional spiropolymers, which accelerates the development of polymerization methodology.