Synthesis of a new DTTA-and 5-phenyl-2,2′-bipyridine-based ditopic ligand and its Eu3+ complex

Abstract

A new ditopic ligand based on diethylenetriamine-N,N,N'',N''-tetraacetate (DTTA) and 5-phenyl-2,2′-bipyridine has been synthesized. The improved method for the synthesis of DTTA tert-butyl ester has been developed. The water-soluble Eu3+∗DTTA complex of this ligand has been prepared, and its photophysical properties have been studied. Due to the presence of an extra chelating unit, 5-phenyl-2,2′-bipyridine, this Eu3+∗DTTA complex demonstrated a strong fluorescence response to the Zn2+ cation (fluorescence enhancement) and the simultaneous fluorescent and phosphorescent response (fluorescence and phosphorescence quenching) to the Cu2+ or Ni2+ cations in aqueous solutions. © 2016 Published by NRC Research Press.