Boron-Functionalised exo-Norbornene Monomers for ROMP: Toward Coordination-Active Poly(norbornene-B-arylene-dioxaborepine)s.

A series of boron-functionalised exo-norbornene monomers bearing boronic ester groups were synthesised via a condensation reaction and subsequently polymerised through ring-opening metathesis polymerisation (ROMP) to afford well-defined poly(norbornene-B-arylene-dioxaborepine)s. The incorporation of Lewis acidic boron centres into the norbornene-derived polymer backbone enables access to coordination-active macromolecular systems with tuneable interactions towards nucleophilic species. The resulting polymers demonstrate enhanced structural definition and stability, thereby confirming the robustness of the synthetic approach and the successful incorporation of boron functionalities into ROMP-derived architectures. This work establishes a general and efficient strategy for the preparation of boron-containing ROMP polymers, providing a versatile platform for the development of coordination-responsive polymeric materials.