Studying the effectiveness of various chromophores of the 5-aryl-2,2-bipyridine series for the sensitization of lanthanide(III) cations

A systematic study of the effectiveness of various chromophores of the 5-aryl-2,2'-bipyridine series was carried out in terms of sensitization of lanthanide(III) cations. For this purpose, the corresponding DTTA-appended 5-aryl-2,2'-bipyridines were synthesized in good yields by using the "1,2,4-triazine" methodology, and their europium(III) and terbium(III) complexes were prepared. The photophysical properties were studied for all the obtained chelates, and the influence of the nature of the aryl substituent of the bipyridine core was estimated. The positive influence of the halogen atoms as well as a methyl group on the efficiency of the lanthanide(III) cation sensibilization was demonstrated. The influence of the nature of the residue of the polyaminocarboxylic acid fragment in the ligand on the luminescent characteristics of its lanthanide complexes was also studied. [GRAPHICS] .