Dynamic kinetic resolution of a tertiary alcohol
Franziska Kühn1, Satoko Katsuragi, Yasuhiro Oki
1Chair of Industrial Organic Chemistry and Biotechnology, Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany. harald.groeger@uni-bielefeld.de.
Chemical Communications (Cambridge, England)
|February 11, 2020
Summary
This study presents the first dynamic kinetic resolution of tertiary alcohols, overcoming steric hindrance challenges. A lipase and oxovanadium catalyst combination achieves high enantiomeric purity for esters.
Area of Science:
- Organic Chemistry
- Enzymatic Catalysis
- Asymmetric Synthesis
Background:
- Tertiary alcohols and esters are challenging substrates for dynamic kinetic resolution due to steric hindrance.
- Compatibility issues arise between racemization conditions and enzymatic resolution processes.
Purpose of the Study:
- To develop the first dynamic kinetic resolution for racemic tertiary alcohols.
- To achieve enantiomerically pure esters from tertiary alcohols via a combined catalytic system.
Main Methods:
- Lipase-catalyzed kinetic resolution of tertiary alcohols.
- In situ racemization of tertiary alcohols using a bio-compatible oxovanadium catalyst.
- Optimization and integration of both catalytic systems for a one-pot process.
Main Results:
- Successful dynamic kinetic resolution of a racemic tertiary alcohol was achieved.
- The combined process yielded the enantiomerically pure ester with >99% enantiomeric excess (ee).
- Conversion exceeded 50% under optimized conditions.
Conclusions:
- This work demonstrates a novel and effective method for the dynamic kinetic resolution of challenging tertiary alcohol substrates.
- The integration of enzymatic resolution with a bio-compatible racemization catalyst opens new avenues in asymmetric synthesis.
- The developed method provides access to enantiomerically pure tertiary alcohol derivatives with high efficiency.
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