Structure Variation and Luminescence Properties of Lanthanide Complexes Incorporating a Naphthalene‐Derived Chromophore Featuring Salicylamide Pendant Arms

Abstract

A new potentially bridging ligand containing two salicylamide pendant arms separated by a 2,3‐dimethoxynaphthalene spacer has been prepared and its coordination chemistry with LnIII ions has been investigated. An analysis of the presented crystal structures indicates that the diversity of these supramolecular structures is mainly dictated by the nature of the metal ions. These compounds represent good examples of tuning crystal structures arising from the flexibility of the ligands and the Ln contraction effect. Luminescence studies showed that the introduction of the methoxyl substituents on the naphthalene backbone lowers the triplet energy and considerably changes the luminescent behaviors of the EuIII and TbIII complexes, which is very different from the literature data on similar compounds. In the emission spectra of the Tb complex the ligand fluorescence remains relatively important because of the back‐energy transfer from the TbIII ion to the ligand, which to the best of our knowledge, may be the first example of salicylamide lanthanide complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Structure variation and luminescence properties of lanthanide complexes with 1,9-bis [2-(2′-picolylaminoformyl)-1,4,7,9-tetraoxadecane

“…320 nm. The obvious changes during the titration in the UV-vis spectrum suggest significant change in the overall electronic structure of the ligands upon addition of Eu 3+ , which is quite different from those reported by us before [8,9]. In addition the large molar absorption coefficient of the ligands indicates favorable conditions for an efficient antenna effect.…”

“…As a result, several fascinating supramolecular structure resulted [6][7][8][9]. Acyclic polyethers offer many advantages in the extraction and analysis (ion selective electrodes) of lanthanides.…”

“…Thus, it was interesting to examine whether the architecture is maintained across the Ln. To date, only few reports are concerned with the diversity of Ln-based structures controlled by the radii of Ln ions [8,[13][14][15][16][17][18][19]. With the aim of investigating such an interesting area, we have now extended our studies of the ligand, 1,9-bis [2-(2 0 -picolylaminoformyl)-1,4,7,9-tetraoxadecane (L) (Scheme 1) both on the diversity supramolecular structure and on the luminescence properties of the Eu(III) complex.…”

A tetradentate bisoxime and its supramolecular nickel(II) cluster: synthesis, crystal structure, and spectral properties

“…In the crystal structure, there are two strong intramolecular O3ÀH3 Á Á Á N1, O5ÀH5 Á Á Á N2 hydrogen bonds between the phenolic hydroxyl and the oxime nitrogen, which generate six-membered S(6) ring motifs (Supplementary material) [31][32][33]. In addition, intermolecular C16-H16 Á Á Á O1 hydrogen bonds link a pair of molecules to produce a 20-membered ring with a graph motif of R 2 2 ð20Þ (Supplementary material) [34,35].…”

Rising profile on the use of metal–organic frameworks (MOFs) for the removal of heavy metals from the environment: an overview

“…The hybrid and dynamic structure of MOFs materials, which include an organic ligand and a metal ion bonded in various geometry, allows a large number of emissive phenomena which can only be seen in few other types of materials, the conjugation and rigidity of the linkers aids the coordination of the central metal (Song et al 2008). MOFs provide a dynamic platform for the production of solid-state luminescent materials as their structure have a high level predictive ability, apart from providing well-defined environments for lumophore which are in crystalline form (Sabbatini et al 1993).…”