Four couples of enantiomerically pure chiral seven-coordinated mononuclear lanthanide complexes, [(L(OEt))Dy((R,R)-Salphen)](2)·3H(2)O (1, L(OEt) = [(Cp)Co(P(O)(OEt)(2))(3)], Cp = cyclopentadiene, Salphen = N,N'-1,2-diphenylethylenebis(salicylideneiminato) dianion), [(L(OEt))Dy((S,S)-Salphen)](2)·3H(2)O (2), [(L(OEt))Dy((R,R)-5-Cl-Salcy)]·CH(3)OH·1/8H(2)O (3, Salcy = N,N'-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion), [(L(OEt))Dy((S,S)-5-Cl-Salcy)]·CH(3)OH·1/8H(2)O (4), [(L(OEt))Tb((R,R)-5-Cl-Salcy)]·CH(3)OH·1/8H(2)O (5), [(L(OEt))Tb((S,S)-5-Cl-Salcy)]·CH(3)OH·1/8H(2)O (6), [(L(OEt))Ho((R,R)-5-Cl-Salcy)]·CH(3)OH·1/8H(2)O (7) and [(L(OEt))Ho((S,S)-5-Cl-Salcy)]·CH(3)OH·1/8H(2)O (8), have been successfully synthesized by using tetradentate chiral salen-type ligands and the Kläui's tripodal ligand of L(OEt). Structural analyses reveal that all compounds have a typical double-decker sandwich structure, and the Ln(iii) ions exhibit a rare seven-coordinated mode, situating in a distorted monocapped triangular prism polyhedron. Circular dichroism (CD) spectra confirm the enantiomeric nature of the optically active complexes and demonstrate that the chirality is successfully transferred from the ligand to the coordination environment of the Ln(iii) ions. Field-induced slow relaxation of the magnetization is observed for complexes 1-4, suggesting that they can be rare chiral single-ion magnets (SIMs) based on the seven-coordinated lanthanide ions.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/c2dt31203d | DOI Listing |
Molecules
November 2024
Hubei Key Laboratory of Radiation Chemistry and Functional Materials, School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning 437100, China.
The design and synthesis of novel lanthanide-based coordination polymers (Ln-CPs) from flexible organic ligands is still attractive and challenging. In this work, two isostructural Ln-CPs with a unique 2D network, namely, [Ln(HL)(DMF)]] (Ln = Dy for , Tb for ) based on a flexible polycarboxylic acid ligand hexakis(4-carboxylato-phenoxy)cyclotriphosphazene (HL), have been solvothermally synthesized and structurally characterized. Significantly, it is the first observation of polycarboxylic acid ligands participating in coordination in the construction of coordination polymers in the form of semi-deprotonation.
View Article and Find Full Text PDFChem Sci
November 2024
University of Angers, CNRS, MOLTECH-ANJOU, SFR MATRIX Angers F-49000 France
The synthesis and whole characterization by a multitechnique approach of an unprecedented dysprosium(iii) 2D metal organic framework (MOF), involving the redox-active tetrathiafulvalene (TTF)-based linker TTF-tetracarboxylate (TTF-TC), are herein reported. The single-crystal X-ray structure, formulated as [Dy(TTF-TC)(HO)]·21HO (1), reveals a complex 2D topology, with hexanuclear Dy clusters as secondary building units (SBUs) interconnected by five linkers, stacked almost parallel in each layer and eclipsed along the [111] direction, leading to the formation of 1D channels filled by water molecules. The mixed valence of the TTF units is confirmed by both bond distance analysis, Raman microscopy and diffuse reflectance spectroscopy, and further supported by band structure calculations, which also predict activated conductivity for this material.
View Article and Find Full Text PDFDalton Trans
November 2024
Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Inorgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Dalton Trans
December 2024
State Key Laboratory of Materials-Oriented Chemical Engineering, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
Two pairs of chiral enantiomers D/L-Dy(PMP)·2HO (D-1/L-1) and D/L-Yb(PMP)·2HO (D-2/L-2) were synthesized by the introduction of enantiomerically pure D/L-PMP (PMP = (phosphonomethyl)proline) ligands into lanthanide coordination chemistry. The chiral characteristics of these products were confirmed by single crystal X-ray diffraction, second harmonic generation (SHG) measurements and circular dichroism (CD) spectroscopy. These complexes are composed of 1D chains constructed from lanthanide ions with a trigonal prismatic coordination geometry and PMP ligands.
View Article and Find Full Text PDFDalton Trans
November 2024
N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky prosp. 31, Moscow 119991, Russian Federation.
The reactions of VOSO·3HO with Na(cbdc) (cbdc - dianion of cyclobutane-1,1-dicarboxylic acid) and lanthanide(III) nitrates taken in a molar ratio of 1 : 2 : 1 were found to yield a series of isostructural heterometallic compounds [NaLn(VO)(cbdc)(HO)] (1Ln, Ln = Tb, Dy, Ho, Er, Tm, Yb). These compounds are constructed from trinuclear anionic units [Ln(VO)(cbdc)(HO)] ({LnV}) linked by Na ions into 1D polymeric chains. The crystal structures of 1Dy and 1Er were determined by single-crystal X-ray diffraction (XRD), and their isostructurality with 1Tb, 1Ho, 1Tm, and 1Yb was proved by powder X-ray diffraction (PXRD).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!