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Updated: May 24, 2026
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
1H,89Y HMQC and further NMR spectroscopic and X-ray diffraction investigations on yttrium-containing complexes
Matthias W Löble1, María Casimiro, Dominique T Thielemann
1Institute of Inorganic Chemistry, Karlsruhe Institute of Technology, Engesserstrasse 15, 76131 Karlsruhe, Germany.
Abstract:
2D (1)H,(89)Y heteronuclear shift correlation through scalar coupling has been applied to the chemical-shift determination of a set of yttrium complexes with various nuclearities. This method allowed the determination of (89)Y NMR data in a short period of time. Multinuclear NMR spectroscopy as function of temperature, PGSE NMR-diffusion experiments, heteronuclear NOE measurements, and X-ray crystallography were applied to determine the structures of [Y(5)(OH)(5)(L-Val)(4)(Ph(2)acac)(6)] (1) (Ph(2)acac=dibenzoylmethanide, L-Val=L-valine), [Y(2)(OTf)(3)] (3), and [Y(2)(4)(OTf)(5)] (5) (2: [(S)P{N(Me)N=C(H)Py}(3)], 4: [B{N(Me)N=C(H)Py}(4)](-)) in solution and in the solid state. The structures found in the solid state are retained in solution, where averaged structures were observed. NMR diffusion measurements helped us to understand the nuclearity of compounds 3 and 5 in solution. (1)H,(19)F HOESY and (19)F,(19)F EXSY data revealed that the anions are specifically located in particular regions of space, which nicely correlated with the geometries found in the X-ray structures.
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