Synthesis and photophysical properties of bis-NHC platinum(ii) complexes bearing bipyridine ligands furnished with two anionic closo-monocarborane clusters [CB11H12]−

Abstract

Four Pt(II) complexes have been synthesized by utilizing the primary bis-NHC ligands and featuring chelating bipyridine ligands decorated with two monoanionic closo-monocarborane clusters. All four complexes exhibited phosphorescence, with complex 2b exhibiting a significant photoluminescence quantum yield of 70% in a 2 wt% PMMA film. The blue shifts of the emission spectra for complexes 2a and 2b in comparison with the complexes 1a and 1b are owing to the cross-coupling position of the pyridine ring to which the clusters [CB₁₁H₁₂]⁻ were attached.