Cyclometalated platinum(II) complex with C^N^N tridentate ligand as sensitizer for lanthanide luminescence

The preparation, characterization and photophysical properties of heterobinuclear complexes {Pt(C^N^N)(Ctriple bond; length of mdashCbpy)}Ln(hfac)3 (C^N^N = 2-(6-(naphthalen-3-yl)-4-phenylpyridin-2-yl)pyridine; HCtriple bond; length of mdashCbpy = 5-ethynyl-2,2′-bipyridine; Ln = Nd, Eu, Yb; hfac = hexafluoroacetylacetonate) are described. With excitation at 390 ⩽ λex ⩽ 500 nm which is the MLCT/LLCT absorption region of the Pt(C^N^N)(Ctriple bond; length of mdashCbpy) chromophore, lanthanide luminescence is successfully attained by Pt → Ln energy transfer from the platinum(II) antenna chromophore to the lanthanide center across the bridging Ctriple bond; length of mdashCbpy ligand.