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Updated: Jul 19, 2026
08:25
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
MTO Schiff-base complexes: synthesis, structures and catalytic applications in olefin epoxidation
Ming-Dong Zhou1, Jin Zhao, Jun Li
1Department of Chemistry, Liaoning University, Chongshan, Middle Road, No. 66, 110036 Shenyang, P.R. China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 27, 2006
Summary
Schiff-base ligands form stable methyltrioxorhenium(VII) complexes. These complexes exhibit unique structures and catalytic properties, but excess ligand causes decomposition.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Coordination Chemistry
Background:
- Schiff-base ligands are versatile organic molecules.
- Methyltrioxorhenium(VII) (MTO) is a known oxidation catalyst.
- The interaction between Schiff-base ligands and MTO is not fully understood.
Purpose of the Study:
- To synthesize and characterize methyltrioxorhenium(VII) complexes with Schiff-base ligands.
- To investigate the structural and electronic properties of these complexes.
- To evaluate their catalytic activity and stability.
Main Methods:
- Synthesis of Schiff-base ligands and their MTO complexes.
- X-ray crystallography for solid-state structure determination.
- (17)O NMR spectroscopy for solution studies.
- Catalytic activity and stability tests.
Main Results:
- Stable Schiff-base MTO complexes were formed via hydrogen transfer.
- Solid-state structures showed distorted trigonal-bipyramidal geometry.
- Solution studies indicated loss of steric differences.
- Catalytic performance was highly dependent on the Schiff base, with excess ligand causing decomposition.
Conclusions:
- Schiff-base ligands form air-stable MTO complexes with unique structural features.
- Ligand structure significantly impacts catalytic activity and stability.
- Careful control of ligand concentration is crucial for optimal MTO catalysis.
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