The discovery of a simple ligand based on acetophenone bearing excellent quantum yields for the excitation of Eu3+ and Tb3+

A new, relatively simple tetra-acid ligand derived from acetophenone was synthesized and its luminescence properties when forming Eu(III) and Tb(III) chelates were evaluated in aqueous and methanol solutions. The titled compound displayed excellent quantum yields of triplet sensitization of lanthanide luminescence (0.20–0.25 for Eu 3+ and 0.95–1.00 for Tb 3+ ). Results suggested that the metal and the cromophore should be in close contact and that the iminodiacetic arms isolate very well the metal from the surrounding OH oscillators which normally quench lanthanide luminescence.