Divalent ytterbium complexes with crown and heterocrown ethers
Philip N Bartlett1, Martin J D Champion, Mark E Light
1School of Chemistry, University of Southampton, Southampton SO17 1BJ, UK. wxl@soton.ac.uk.
Dalton Transactions (Cambridge, England : 2003)
|December 11, 2014
Summary
Researchers synthesized novel ytterbium(ii) complexes using macrocyclic ligands. The study details the first Ytterbium(ii)-selenoether coordination, revealing distorted 8-coordination in a new ytterbium complex.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Coordination Chemistry
Background:
- Ytterbium(II) complexes are of interest due to their unique electronic properties.
- Macrocyclic ligands offer versatile coordination environments for metal ions.
- Exploration of novel donor atoms in macrocyclic ligands can lead to new complex types.
Purpose of the Study:
- To synthesize and characterize unusual ytterbium(II) complexes.
- To investigate the coordination behavior of mixed O4X2-donor macrocyclic ligands with ytterbium(II).
- To report the first example of Ytterbium(II)-selenoether coordination.
Main Methods:
- Synthesis of ytterbium(II) complexes with O4X2-donor macrocyclic ligands (X = O, NH, S, Se).
- Structural characterization using X-ray crystallography.
- Spectroscopic analysis to confirm complex formation.
Main Results:
- Several novel ytterbium(II) complexes were successfully synthesized.
- The crystal structure of [YbI2([18]aneO4Se2)] revealed distorted 8-coordination.
- This represents the first reported instance of Ytterbium(II) coordinating to a selenoether donor.
Conclusions:
- Mixed O4X2-donor macrocyclic ligands can effectively stabilize ytterbium(II).
- Distorted 8-coordination is a common motif in these complexes.
- The findings expand the known coordination chemistry of ytterbium(II), particularly with heavier chalcogen donors.
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