Binuclear Lanthanide(III) Complexes with Chiral Ligands: Dynamic Equilibria in Solution and Binding with Nucleotides Studied by Spectroscopic Methods. Issue 4 (6th April 2020)

• Record Type: Journal Article
• Authors: Sahoo, Jashobanta; Wu, Tao; Klepetářová, Blanka; Valenta, Jan; Bouř, Petr
• Is Part Of: ChemPlusChem. Volume 85:Issue 4(2020)
• Page Start: 694
• Page End: 700
• Publication Date: 2020-04-06
• Subjects: chiral ligands -- circularly polarized luminescence -- lanthanides -- nucleotides -- Raman optical activity; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.202000182
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: Binuclear lanthanide complexes of Eu(III) and Sm(III) were obtained in the presence of chiral ligand 1, 2‐( R, R + S, S )‐N, N'‐bis(2‐pyridylmethylene), 2‐diamine. An unusual structure of the Eu(III) compound with two lanthanide atoms connected through two chlorines was determined by X‐ray crystallography. In solution, the dimer coexists with a monomeric complex, and the stability of the binuclear form depends on the solvent and concentration. The dimer‐monomer equilibrium was monitored by circularly polarized luminescence (CPL) measured on a Raman optical activity (ROA) spectrometer, where both forms provided large CPL anisotropic ratios of up to 5.6×10 −2 . Monomer formation was favored in water, whereas the dimer was stabilized in methanol. When mixed with adenosine phosphates, AMP gave much smaller CPL than ADP and ATP, indicating a high affinity of the Eu (III) complex for the phosphate group, which in connection with the ROA/CPL technique can be developed into a bioanalytical probe. Abstract : Chiral complexes : Chiral binuclear lanthanide complexes were obtained from chiral Schiff base ligands. An equilibrium between the dimer and monomer, and affinity for the phosphate group were monitored by circularly polarized luminescence (CPL) measured on a Raman optical activity (ROA) spectrometer. The ROA/CPL method is promising tool for future lanthanide‐nucleotide binding studies.