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We report here the characterization in solution (NMR, luminescence, MS) and the solid-state (X-ray crystallography, IR) of complexes between phenacyldiphenylphosphine oxide and five Ln( iii ) ions (Sm, Eu, Gd, Tb, Dy). Four single crystal X-ray structures are described here showing a 1 : 2 ratio between the Ln 3+ ions Eu, Dy, Sm and Gd and the ligand, where the phosphine oxide ligands are bound in a monodentate manner to the metal center. A fifth structure is reported for the 1 : 2 Eu(NO 3 ) 3 -ligand complex showing bidentate binding between the two ligands and the metal center. The solution coordination chemistry of these metal complexes was probed by 1 H, 13 C and 31 P NMR, mass spectrometry, and luminescence experiments. The title ligand has the capability to sensitize Tb 3+ , Dy 3+ , Eu 3+ and Sm 3+ leading to metal-centered emission in solutions of acetonitrile and methanol and in the solid state.
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Detection of phosphates in water utilizing a Eu 3+ -mediated relay mechanism
Three carboxamidequinoline ligands were synthesized and their complexes with Eu 3+ were used for recognition and detection of organic/inorganic phosphates in water. The signal transduction process is based on an “On–Off–On” switch in the fluorescence signal utilizing changes in the intramolecular charge transfer (ICT). The fluorescence emission of ligands is quenched upon exposure to the Eu 3+ (Off signal). Following the addition of the phosphate analytes the ligand–Eu 3+ complex disassembles, which results in the regeneration of the original emission of the ligand (On signal). In general, the Eu 3+ complexes show higher affinity towards adenosine 5′-triphosphate (ATP) and lower affinity to other phosphates, namely adenosine 5′-diphosphate (ADP), adenosine 5′-monophosphate (AMP), pyrophosphate (H 2 P 2 O 7 2− , PPi), and dihydrogenphosphate (H 2 PO 4 − , Pi).
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- Award ID(s):
- 2102581
- PAR ID:
- 10329419
- Date Published:
- Journal Name:
- New Journal of Chemistry
- Volume:
- 46
- Issue:
- 4
- ISSN:
- 1144-0546
- Page Range / eLocation ID:
- 1839 to 1844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1NJ04578D
