Insights into the Complexation of Lanthanides with Dibenzyl-Diaza-18-Crown-6 Ethers
Abstract: The investigation aimed to enhance the understanding of the coordination chemistry of lanthanide elements with aza-crown ethers. A group of lanthanide metal complexes with the general formula [Ln(SCN)3(C26H38N2O4)] (Ln3+= La3+, Nd3+, Eu3+) and [Ln(NO3)5.H2O(C26H38N2O4)] (Ln3+= La3+, Nd3+, Gd3+) has been synthesized and their structures in solution were determined using variable-temperature 1H NMR spectroscopy. The interactions between the donor atoms and the central atom were clearly reflected in the chemical shifts of protons on the crown moiety. Notably, the chemical shifts of protons adjacent to oxygen atoms were less sensitive to temperature variations compared to those of protons adjacent to nitrogen atoms. Additionally, the chemical shifts were found to depend on the type of anion and the ionic radius of the guest molecule. The 1H NMR analysis provided a compelling explanation for the selectivity of this type of ligands toward lanthanum compared to other lanthanide elements. These findings confirmed that La?? behaves distinctly in its complexes with dibenzo-diaza-18-crown-6 (DD18C6) compared to other lanthanide elements of similar composition.
Keywords: lanthanides, crown ethers, host-guest, complexation, coordination
How to Cite?: Abdussalam Salhin Mohamed Ali, Muhammad Idiris Saleh, "Insights into the Complexation of Lanthanides with Dibenzyl-Diaza-18-Crown-6 Ethers", Volume 14 Issue 7, July 2025, International Journal of Science and Research (IJSR), Pages: 695-702, https://www.ijsr.net/getabstract.php?paperid=SR25628024122, DOI: https://dx.doi.org/10.21275/SR25628024122