Highly-Luminescent DTTA-Appended Lanthanide Complexes of 4-(Multi)fluoroaryl-2,2′-bipyridines: Synthesis and Photophysical Studies

Abstract A number of new water-soluble 2,2′-bipyrdine Eu(III) and Tb(III) complexes have been prepared. The complexes are based on 4-(multi)fluoroaryl-2,2′-bipyridines bearing diethylenetriaminetetraacetic acid (DTTA) residue at C6 position. The study of their photophysical properties demonstrated the advantages of introducing fluorine atoms into the ligands. Strong lanthanide cation luminescence was observed, an increase in the quantum yield was especially noticeable for fluorine-containing Tb(III) complexes. An increase in solubility was also observed in comparison with some previously described complexes, including bromine- or chlorine-containing ones, whereas values of the Ln(III) cation luminescence quantum yields were found to be comparable.