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Luminescent Metal Complexes Featuring Photophysically Innocent Boron Cluster Ligands.

ABSTRACT: We report the synthesis and characterization of a series of d⁸ metal complexes featuring robust and photophysically innocent strong-field chelating 1,1'-bis(o-carborane) (bc) ligand frameworks. A combination of UV-Vis spectroscopy, single crystal X-ray structural analysis, and DFT calculations of these species suggest that the dianionic bc ligand does not contribute to any visible metal-to-ligand charge transfer (MLCT) transitions, yet it provides a strong ligand field in these complexes. Furthermore, a bc-based Pt(II) complex containing a 4,4'-di-tert-butyl-2,2'-bipyridine ligand (dtb-bpy) has been prepared and was found to display blue phosphorescent emission dominated by MLCT from the Pt(II) center to the dtb-bpy ligand. Importantly, the bulky three-dimensional nature of the bc ligand precludes intermolecular Pt(II)⋯Pt(II) interactions in the solid state where the resulting compounds retain their emission properties. This study opens a potentially new avenue for designing organic light-emitting diode (OLED) materials with tunable properties featuring photophysically innocent boron-rich cluster ligands.

SUBMITTER: Kirlikovali KO

PROVIDER: S-EPMC5300762 | biostudies-literature |

REPOSITORIES: biostudies-literature

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