Synthesis of electron-accepting polymers containing phenanthra-9,10-quinone units

Polymers containing 9,10-phenanthraquinone moieties as part of an extended π-electron system have been prepared by Suzuki couplings between 2,7- or 3,6-dibromophenanthraquinone and 9,9-dioctylfluorene-2,7-diboronic acid bispinacol ester. Closely related model compounds were prepared similarly. All the products were characterised by FT-IR, 1H NMR and UV-vis/fluorescence spectroscopy and, where relevant, mass spectrometry. Cyclic voltammetry measurements indicate that these materials display electron affinities of up to 4.0 eV. This value is one of the highest reported for conjugated polymers.