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Polymers containing iminofuran (PIFs) are rarely reported due to the lack of simple and effective synthesis methods. In this work, a novel multicomponent cyclopolymerization (MCCP) of diisocyanides, activated alkynes, and 1,4‐dibromo‐2,3‐butanedione using catalyst‐free one‐pot reactions under mild conditions to prepare PIFs containing bromomethyl groups is reported. PIFs with good solubility and thermal stability are obtained with high Mws (up to 19 600) and good yields (up to 89.5%) under optimized polymerization conditions. The structure of the PIFs is characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and gel permeation chromatography. The photophysical properties indicate that polymers P1a2b3 and P1c2b3 have cluster‐triggered emission characteristics. Thin films made from PIFs quickly degrade under UV irradiation. Moreover, the obtained polymers are decorated with bromomethyl and carboxylate groups in the side chain, which can be postfunctionalized to prepare multifunctional materials, such as star branched polymers and biomedical carrier materials. Thus, this work not only enriches the field of polymerization based on isocyanates and activated alkynes but also provides a facile strategy toward functional iminofuran polymers.

Multicomponent spiropolymerization (MCSP) provides an efficient synthetic tool for the construction of spiropolymers based on nonspiro monomers. In this study, a method of MCSP using diisocyanides 1, diethyl acetylenedicarboxylate 2, and halogenated quinones 3 is developed for the in situ construction of bis‐spiropolymers with high molecular weights (Mw up to 29 200) and good yields (up to 87.7%) under mild reaction conditions. The structure of the obtained bis‐spiropolymers is confirmed by gel permeation chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance analysis. Halogenated bis‐spiropolymers show good thermal stability, good solubility, and film‐forming ability. The photosensitizer rhodamine B is used as a doping agent to induce the photodegradation of the polymer P1a3c into small‐molecule segments, which results in the slow release of halogenated spiro‐groups under irradiation with simulated sunlight. This finding reveals that P1a3c has the potential to be applied in pesticides. Therefore, this MCSP is a novel method for preparing halogen‐containing bis‐spiropolymers, which accelerates the development of multifunctional polymer materials.

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 w up 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.

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