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 ligand of bis-NHC (dpdb, dpdi) and featuring cyclometalated ligands of bipyridine (bpy) decorated with two monoanionic closo-monocarborane clusters. All four complexes exhibited phosphorescence, with complex 2b exhibiting a significant photoluminescent quantum yield of 70% in a 2 wt% PMMA film. The The blue shifts of the emission spectra for complexes 2a and 2b in comparison to the complexes 1a and 1b owing to the cross-coupling position of the pyridine ring which the clusters [CB11H12]− were attached to.