Norbornene-based copolymers containing platinum complexes and bis(carbazolyl)benzene groups in their side-chains

Two norbornene-functionalized tetradentate cyclometalated platinum(II) complexes were synthesized and copolymerized with a bis(carbazolyl)benzene-based comonomer using ring-opening metathesis polymerization (ROMP). The copolymers are soluble in common solvents and the molecular weights of these copolymers can be well controlled as a result of the living character of the ROMP. The photophysical and electrochemical properties of the copolymers were compared to their corresponding small molecules. The copolymers showed almost identical photophysical and electrochemical properties demonstrating the inertness of the polymer backbone toward the photophysical properties of the tethered platinum complexes. All complexes exhibit bright photoluminescence in the green region with lifetimes around 0.4 μs and solution phosphorescence quantum efficiencies as high as 0.56, which suggest that these materials could be interesting for OLED applications.