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Updated: May 27, 2026
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Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
Improved ruthenium catalysts for Z-selective olefin metathesis
Benjamin K Keitz1, Koji Endo, Paresma R Patel
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|November 22, 2011
Summary
New ruthenium catalysts enable Z-selective olefin metathesis. Nitrato-type ligands significantly improve activity and selectivity, achieving high turnover numbers for industrial applications.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Olefin metathesis is a powerful carbon-carbon bond-forming reaction.
- Achieving high Z-selectivity in olefin metathesis remains a challenge.
- Ruthenium catalysts are widely used but require optimization for specific selectivities.
Purpose of the Study:
- To synthesize and evaluate novel C-H-activated ruthenium catalysts for Z-selective olefin metathesis.
- To investigate the impact of ligand modifications on catalyst performance.
- To explore the potential of these catalysts in synthesizing industrially relevant compounds.
Main Methods:
- Synthesis of new ruthenium complexes featuring modified N-heterocyclic carbene and carboxylate ligands.
- Evaluation of catalyst performance in various olefin metathesis reactions, including cross-metathesis.
- Systematic variation of ligand types (monodentate vs. bidentate, carboxylate vs. nitrato).
Main Results:
- Ligand modification significantly impacts catalyst activity and Z-selectivity.
- Substitution of bidentate with monodentate ligands decreased performance.
- Nitrato-type ligands demonstrated superior activity and selectivity compared to carboxylates.
- Turnover numbers approaching 1000 were achieved for cross-metathesis reactions.
Conclusions:
- Novel C-H-activated ruthenium catalysts with improved Z-selectivity have been developed.
- Nitrato-type ligands are key to enhancing metathesis activity and selectivity.
- These catalysts show promise for the efficient synthesis of valuable chemical products.
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