Synthesis and luminescence properties of cyclometalated iridium(III) complexes incorporating conjugated benzotriazole units

Publication date: Available online 17 February 2018 Source:Journal of Organometallic Chemistry Author(s): Emily E. Langdon-Jones, Benjamin D. Ward, Simon J.A. Pope The stepwise synthesis of imidazo[4,5-f]-1,10-phenanthroline-based ligands that incorporate conjugated benzotriazole units are described. Corresponding cyclometalated Ir(III) complexes of the type [Ir(CˆN)2(L)]BF4 (where CˆN = cyclometalating ligand; L = phenanthroline type ligand) are reported. The complexes were characterized using a variety of techniques, including IR, NMR, UV-vis. spectroscopies, mass spectrometry and cyclic voltammetry. The [Ir(ppy)2(L)]BF4 complexes display luminescence in the visible region with the benzotriazole variants showing long-lived blue shifted emission around 495 nm. Supporting TD-DFT calculations predict that a mixture of MLCT and LLCT character may contribute to the HOMO-LUMO transition of the benzotriazole derivatives. Graphical abstract

Source: Journal of Organometallic Chemistry - February 18, 2018 Category: Chemistry Source Type: research