Cyclometallated platinum(II) complexes incorporating ethynyl-flavone ligands: switching between triplet and singlet emission induced by selective binding of Pb2+ ions

Platinum-ethynylflavone complexes featuring various pole ether arms display (IL)-I-3 phosphorescence associated with the appended flavone perturbed by the platinum centre (tau similar to 20 mu s), but switch dramatically to flavone-localised (IL)-I-1 fluorescence (tau similar to 2 ns) upon selective binding of Ph2+.