AI Article Synopsis
- Researchers explored the self-assembly of lanthanide complexes using two new tripodal ligands (L2 and L3) anchored to a rigid triptycene, with functional groups to improve solubility.
- The study involved synthesizing and characterizing these ligands, assessing their coordination through speciation studies using NMR and ESI-MS.
- It was found that the tetranuclear complexes formed were stable, but stability declined with heavier lanthanides due to steric hindrance and the effects of PEG groups, although luminescence was enhanced despite one water molecule coordinating with the metal ion.
Article Abstract
In this Article, we report the self-assembly of lanthanide complexes formed with two new tripodal ligands, L2 and L3, where binding strands are connected to a rigid triptycene anchor. The pyridine moieties are functionalized with methoxy and PEG groups to enhance ligand solubility and to evaluate the effect of these substituents on lanthanide coordination. These ligands were successfully synthesized and characterized, and their coordination properties were examined along the lanthanide series through speciation studies with NMR and ESI-MS. Well-defined tetranuclear complexes are formed with both ligands, but their stabilities with heavier lanthanides are considerably reduced, especially for complexes with L3. This is attributed to a destabilizing effect of pending PEG arms in combination with increased steric hindrance between binding strands upon complexation with smaller cations. The sensitization of lanthanide luminescence in tetranuclear complexes occurs despite one water molecule being coordinated to a metal ion.
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| http://dx.doi.org/10.1021/acs.inorgchem.6b02900 | DOI Listing |
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