Synthesis and characterization of 8-hydroxyquinolinolato-iridium(III) complex grafted on polyhedral oligomeric silsesquioxane core

In this study, a new iridium(III) complex containing coumarin derivative as the cyclometalated ligand (L) and 7-allyl-8-hydroxyquinoline (Hq-allyl) as the ancillary ligand, Ir(III)bis(3-(pyridin-2-yl)coumarinato N,C 4 )(7-allyl-8-hydroxyquinolinolato) [Ir(L) 2 (q-allyl)], was firstly synthesized as the emissive iridium complex. Then a macromolecule consisting of the emissive iridium complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core, 7Cz-Ir(L) 2 (q)-POSS, was successfully synthesized by hydrosilylation reaction in the presence of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane (Pt-dvs) as the catalyst. The macromolecule has good thermal stability due to the significant effect of the POSS core, and its photoluminescence performance is improved because the POSS core reduced interactions among the emissive units and diminished concentration quenching in the solid state.