Blue Phosphorescent Zwitterionic Iridium(III) Complexes Featuring Weakly Coordinating nido-Carborane-Based Ligands
- 22 November 2016
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 138 (48), 15758-15765
- https://doi.org/10.1021/jacs.6b10232
Abstract
We report the development of a new class of phosphorescent zwitterionic bis(heteroleptic) Ir(III) compounds containing pyridyl ligands with weakly coordinating nido-carboranyl substituents. Treatment of phenylpyridine-based Ir(III) precursors with C-substituted ortho-carboranylpyridines in 2-ethoxyethanol results in a facile carborane deboronation and the formation of robust and highly luminescent metal complexes. The resulting nido-carboranyl fragments associate with the cationic Ir(III) center through primarily electrostatic interactions. These compounds phosphoresce at blue wavelengths (450-470 nm) both in a poly(methyl methacrylate) (PMMA) matrix and in solution at 77 K. These complexes display structural stability at temperatures beyond 300 °C and quantum yields greater than 40%. Importantly, the observed quantum yields correspond to a dramatic 10-fold enhancement over the previously reported Ir(III) congeners featuring carboranyl-containing ligands in which the boron cluster is covalently attached to the metal. Ultimately, this work suggests that the use of a ligand framework containing a weakly coordinating anionic component can provide a new avenue for designing efficient Ir(III)-based phosphorescent emitters.Funding Information
- 3M
- Department of Chemistry and Biochemistry, University of California, Los Angeles
This publication has 100 references indexed in Scilit:
- Carborane-Based Metal–Organic Framework with High Methane and Hydrogen Storage CapacitiesChemistry of Materials, 2013
- Perhalogenated Carba‐closo‐dodecaborate Anions as Ligand Substituents: Applications in Gold CatalysisAngewandte Chemie, 2013
- Synthesis, Characterization, and Selected Properties of 7‐ and 12‐Ammoniocarba‐closo‐dodecaboranesEuropean Journal of Inorganic Chemistry, 2012
- Improved Efficiency in Blue Phosphorescent Organic Light‐Emitting Devices Using Host Materials of Lower Triplet Energy than the Phosphorescent Blue EmitterAdvanced Functional Materials, 2011
- Coordination of the nido‐carboranyldiphosphine ligand to ruthenium(II): the first example of the tricoordinating capacity of the 7,8‐(PPh2)2‐7,8‐C2B9H10 moietyApplied Organometallic Chemistry, 2003
- Synthesis of Mono- and Dihalogenated Derivatives of (Me2S)2B12H10 and Palladium-Catalyzed Boron−Carbon Cross-Coupling Reactions of the Iodides with Grignard ReagentsInorganic Chemistry, 2003
- Luminescentnido-Carborane−Diphosphine Anions [(PR2)2C2B9H10]-(R = Ph,iPr). Modification of Their Luminescence Properties upon Formation of Three-Coordinate Gold(I) ComplexesInorganic Chemistry, 2003
- S-Alkylation and S-Amination of Methyl Thioethers − Derivatives ofcloso-[B12H12]2-. Synthesis of a Boronated Phosphonate,gem-Bisphosphonates, and Dodecaborane-ortho-carborane OligomersJournal of the American Chemical Society, 2002
- Stability and Three-Dimensional Aromaticity ofcloso-Monocarbaborane Anions, CBn-1Hn-, andcloso-Dicarboranes, C2Bn-2HnInorganic Chemistry, 1998
- Fluorination of deltahedral closo-borane and -carborane anions with N-fluoro reagentsJournal of Fluorine Chemistry, 1998