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Published on: April 14, 2020
2,2'-bipyridine lariat calixcrowns: a new class of encapsulating ligands forming highly luminescent Eu3+ and Tb3+
1Dipartimento di Chimica Organica e Industriale dell'Universita, Parma, Italy.
Abstract:
A new class of calix[4]arene crown ethers with one or two bipyridines appended to the polyether ring (lariat calixcrowns) have been designed and synthesized; the luminescence properties of their Eu3+ and Tb3+ complexes have been studied in acetonitrile. In this solvent, long lifetimes for the metal emitting states and high metal-luminescence intensities obtained upon ligand excitation have been observed in both Eu3+ and Tb3+ complexes. The association constants in methanol have been determined for some of the complexes studied.
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