Synthesis and luminescence of poly(phenylacetylene)s with pendant iridium complexes and carbazole groups

Poly(phenylacetylene)s containing pendant phosphorescent iridium complexes have been synthesized and their electrochemical, photo-and electroluminescent properties studied. The polymers have been synthesized by rhodium-catalyzed copolymerization of 9-(4-ethynylphenyl)carbazole (CzPA) and phenylacetylenes (C¿N)2Ir(¿2-O,O'-MeC(O)CHC(O)C6H 4C¿CH-4) (C¿N = ¿2-N,C1-2- (pyridin-2-yl)phenyl (IrppyPA) or ¿2-N,C 1-2-(isoquinolin-1-yl)phenyl (IrpiqPA)). In addition, organic poly(phenylacetylene)s with pendant carbazole groups have been synthesized by rhodium-catalyzed copolymerization of CzPA and 1-ethynyl-4-pentylbenzene. Complex (C¿N)2Ir(¿2- O,O'-MeC(O)CHC(O)Ph) (IrpiqPh; C¿N = 2-(isoquinolin-1-yl)phenyl- ¿2-N,C1) was prepared and characterized. While the copolymers of the Irppy series were weakly phosphorescent, those of the Irpiq series displayed at room temperature intense emissions from the carbazole (fluorescence) and iridium (phosphorescence) emitters, being the latter dominant when the spectra were recorded using polymer films. Triple layer OLED devices employing copolymers of the Irpiq series or the model complex IrpiqPh yielded electroluminescence with an emission spectra originating from the iridium complex and maximum external quantum efficiencies of 0.46% and 2.99%, respectively. © 2010 Wiley Periodicals, Inc.