Intramolecular dynamics of lanthanide(III) tetraoxadiaza macrocycle complexes in solution as studied by NMR

S. P. Babailov, L. D. Nikulina, J. H. Krieger

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

1H and 13C NMR and 1H NMR relaxation spectroscopy (RS) measurements are reported for the CDCl3 and CD 2Cl2 solutions of [La(NO3)3 (diaza-18-crown-6)] (I), [Pr(NO3)3 (diaza-18-crown-6)] (II) and [Nd(NO3)3 (diaza-18-crown-6)] (III) complexes. Temperature dependencies of the 1H NMR spectra of II have been analyzed using the dynamic NMR methods for multi-site exchange. Enantiomeric isomer interconversion in II is characterized by ΔH‡ = 21.5 ± 4 kJ mol-1. Studies of the values of the lanthanide-induced shifts and the longitudinal relaxation rate enhancement revealed that the structure of complexes in solution is similar to that reported for the [La(NO3)3(18-crown-6)] complex in the crystal state. Nevertheless, it appears that the principal values of the molar paramagnetic susceptibility tensor (χi) significantly differ in complexes II and III. The possible reasons for the different characteristics of these complexes are discussed.

Original languageEnglish
Pages (from-to)25-29
Number of pages5
JournalJournal of Inclusion Phenomena and Macrocyclic Chemistry
Volume43
Issue number1-2
DOIs
Publication statusPublished - 2002
Externally publishedYes

Fingerprint

Lanthanoid Series Elements
rare earth elements
Nuclear magnetic resonance
nuclear magnetic resonance
isomers
crystals
spectroscopy
Isomers
Tensors
temperature
Magnetic Resonance Spectroscopy
Spectroscopy
tensors
magnetic permeability
Crystals
Temperature
18-crown-6
augmentation
shift
methodology

Keywords

  • Complexes of lanthanides
  • Crown ethers
  • Dynamic NMR
  • Enthalpy of activation
  • Molecular dynamics

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Cite this

Intramolecular dynamics of lanthanide(III) tetraoxadiaza macrocycle complexes in solution as studied by NMR. / Babailov, S. P.; Nikulina, L. D.; Krieger, J. H.

In: Journal of Inclusion Phenomena and Macrocyclic Chemistry, Vol. 43, No. 1-2, 2002, p. 25-29.

Research output: Contribution to journalArticle

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