Modular In Situ Functionalization Strategy: Multicomponent Polymerization by Palladium/Norbornene Cooperative Catalysis.

Herein, we report a cooperatively palladium/norbornene-catalyzed polymerization, which simplifies the synthesis of functional aromatic polymers, including conjugated polymers. Specifically, an A2 B2 C-type multicomponent polymerization that is based on an ortho amination/ipso alkynylation reaction was developed for the preparation of various amine-functionalized arylacetylene-containing polymers. Within a single catalytic cycle, the amine side chains are site-selectively installed in situ by C-H activation during the polymerization process, which represents a major difference from conventional cross-coupling polymerizations. This "in situ functionalization" strategy enables the modular incorporation of functional side chains starting from simple monomers, thereby conveniently affording a diverse range of functional polymers.