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Updated: Nov 1, 2025
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Exploiting complementary ligands for the construction of square antiprismatic monometallic lanthanide SMMs
Yushu Jiao1, Sidra Sarwar2, Sergio Sanz3
1Institute of Inorganic Chemistry, RWTH Aachen University, 52056 Aachen, Germany. paul.koegerler@ac.rwth-aachen.de.
Abstract:
The methylation of p-tert-butylcalix[4]arene in the distal 1,3-phenolic sites provides the ligand H2L = {p-tert-butylcalix[4](OMe)2(OH)2arene} that enables construction of heteroleptic mononuclear lanthanide complexes. The reaction of (N(nBu)4)(acac) (Hacac = acetylacetone), MIIICl3 and H2L under Schlenk conditions results in the formation of a family of (N(nBu)4)[MIIIL(acac)2] complexes where M = Y (1), Gd (2), Tb (3) and Dy (4). The metal ions are eight-coordinate in distorted square-antiprismatic coordination geometries, resulting in slow relaxation of the magnetisation for the Tb derivative.
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