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Trivalent rare-earth metal cyclic (alkyl)(amino)carbene complexes
Yuyuan Xiao1, Ziyu Liu1, Jiefeng Liang1
1Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China. wlhuang@pku.edu.cn.
Dalton Transactions (Cambridge, England : 2003)
|October 4, 2022
Summary
Researchers synthesized novel rare-earth metal complexes featuring cyclic (alkyl)(amino)carbene ligands. These findings expand the coordination chemistry of trivalent rare-earth metals with advanced carbene ligands.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Rare-Earth Element Science
Background:
- Cyclic (alkyl)(amino)carbene ligands exhibit strong σ-donating and π-accepting properties.
- Trivalent rare-earth metal complexes with CAAC ligands are not well-established.
Purpose of the Study:
- To synthesize and characterize novel rare-earth metal CAAC complexes.
- To investigate the electronic structures and bonding interactions in these complexes.
Main Methods:
- Synthesis of mono-CAAC rare-earth metal trisalkyl complexes using M(CH2SiMe3)3(THF)2 precursors.
- Synthesis of bis(CAAC)-stabilized rare-earth metal triiodide complexes using MI3(Et2O) precursors.
- Characterization via X-ray crystallography, elemental analysis, NMR spectroscopy, and DFT calculations.
Main Results:
- Successfully synthesized and characterized mono-CAAC rare-earth metal trisalkyl complexes (RCAAC)M(CH2SiMe3)3 (M = Sc, Y, Lu; R = Me, Et).
- Obtained bis(CAAC)-stabilized rare-earth metal triiodide complexes (MeCAAC)2MI3 (M = Y, Yb).
- DFT calculations revealed CAAC ligands act as σ-donors, with potential π-bonding upon reduction.
Conclusions:
- This study establishes new classes of trivalent rare-earth metal CAAC complexes.
- The findings provide insights into the electronic properties and bonding of CAAC ligands in rare-earth chemistry.
- These complexes represent a significant advancement in the coordination chemistry of rare-earth elements.
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