Cobalt-Catalyzed Multicomponent Polyannulation toward Luminescent and Chiroptical Poly(quinazoline) Derivatives

Developing facile and efficient strategies to access novel fused heterocyclic polymers with well-defined structures and advanced functionalities is of great academic and industral significance. Herein, we report a cobalt-catalyzed multicomponent polyannulation method that directly converts readily available 2-isocyanobenzonitrile derivatives, disulfonyl azides, and diamines into well-defined poly(quinazoline) derivatives in a one-pot and atom-economical manner. This polymerization proceeds efficiently under simple conditions and exhibits broad monomer compatibility, affording a series of multisubstituted poly(quinazoline)s with ultrahigh absolute molar mass values of up to 4.06 × 106 g/mol in high yields of up to 99%. The imine-substituted quinazoline units and heteroatom-rich backbones endow the polymers with excellent solubility, high thermal stability, bright intrinsic luminescence, and versatile postmodification capability. Incorporation of chiral units further produces fused heterocyclic polymers with pronounced circular dichroism and circularly polarized luminescence. Moreover, acid-triggered hydrolysis enables the facile contruction of diverse poly(quinazolinone) structures, allowing dynamic regulation of hydrogen-bonding networks and chiroptical responses. This work provides a poweful synthetic platform for creating fused heterocyclic polymers with diversified structures and multifunctional properties.