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Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Supported chiral Mo-based complexes as efficient catalysts for enantioselective olefin metathesis
Sarah J Dolman1, Kai C Hultzsch, Frédéric Pezet
1Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Journal of the American Chemical Society
|September 2, 2004
Summary
Seven new polymer-supported chiral molybdenum (Mo)-based complexes were synthesized and tested for asymmetric ring-closing and ring-opening metathesis reactions. These catalysts offer high reactivity and enantioselectivity, with reduced metal impurities in products.
Area of Science:
- Organometallic Chemistry
- Polymer Chemistry
- Asymmetric Catalysis
Background:
- Developing efficient and recyclable chiral catalysts is crucial for sustainable synthesis.
- Polymer-supported catalysts offer advantages in separation and purification.
- Molybdenum-based complexes are known for their catalytic activity in metathesis reactions.
Purpose of the Study:
- To synthesize and characterize novel polymer-supported chiral Mo-based complexes.
- To evaluate the catalytic performance of these supported catalysts in asymmetric ring-closing (ARCM) and ring-opening (AROM) metathesis reactions.
- To investigate the influence of polymer support properties, such as cross-linking, on catalytic efficiency and enantioselectivity.
Main Methods:
- Synthesis of polystyrene-based and polynorbornene-based chiral Mo complexes.
- Testing catalytic activity in various ARCM and AROM reactions.
- Analysis of reactivity, enantioselectivity, and metal impurity levels in products.
Main Results:
- Seven new polymer-supported chiral Mo-based complexes were successfully synthesized.
- Catalytic activities in ARCM and AROM reactions were competitive with homogeneous counterparts.
- Lower cross-linking in polymer supports enhanced reaction efficiency and asymmetric induction.
- Products exhibited significantly lower metal impurities compared to those from homogeneous catalysts.
Conclusions:
- Polymer-supported chiral Mo-based complexes are effective catalysts for asymmetric metathesis.
- Catalyst recyclability and reduced metal contamination are key advantages.
- Optimizing polymer support properties can further improve catalytic performance.
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