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Updated: Sep 21, 2025
12:19
Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
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Partial Kinetic Resolution of Oxanorbornenes by Ring-Opening Metathesis Polymerization with a Chiral Ruthenium
Christopher S Daeffler1, Garret M Miyake1, Jean Li1
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, MC 164-30, Pasadena, California 91125, United States.
ACS Macro Letters
|June 2, 2022
Summary
This study introduces kinetic resolution by ring-opening metathesis polymerization (KR-ROMP). Selectivity varies with solvent, suggesting chiral polymer structures influence the reaction outcome.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Catalysis
Background:
- Ring-opening metathesis polymerization (ROMP) is a powerful tool for polymer synthesis.
- Kinetic resolution (KR) is crucial for obtaining enantiomerically pure compounds.
- Combining KR with ROMP presents unique challenges and opportunities.
Purpose of the Study:
- To report the first instance of kinetic resolution via ring-opening metathesis polymerization (KR-ROMP).
- To investigate the influence of reaction conditions, specifically solvents, on the selectivity of KR-ROMP.
- To explore the role of polymer chain structure in modulating resolution selectivity.
Main Methods:
- Utilizing chiral catalysts for ring-opening metathesis polymerization.
- Monitoring polymerization progress and enantioselectivity over time.
- Analyzing the effect of different solvents (tetrahydrofuran, dichloromethane, toluene) on reaction selectivity.
Main Results:
- Demonstrated successful KR-ROMP, achieving kinetic resolution during polymerization.
- Observed significant solvent-dependent variations in selectivity (S).
- In tetrahydrofuran and dichloromethane, selectivity increased with reaction time; in toluene, it decreased.
- Identified a correlation between changing selectivity and the formation of chiral secondary polymer structures.
Conclusions:
- Kinetic resolution by ring-opening metathesis polymerization (KR-ROMP) is feasible.
- Solvent choice critically impacts KR-ROMP selectivity.
- The evolving chiral secondary structure of the polymer chain is a key factor influencing resolution efficiency.
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