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Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
An efficient and practical chemoenzymatic preparation of optically active secondary amines
Shanghui Hu1, David Tat, Carlos A Martinez
1Chemical Research & Development, Pfizer Global Research and Development, La Jolla Laboratories, 10578 Science Center Drive, San Diego, California 92121, USA. shanghui.hu@pfizer.com
Organic Letters
|September 24, 2005
Summary
A new chemoenzymatic method efficiently produces chiral secondary amines using oxalamic esters for enzyme-catalyzed kinetic resolution. This approach yields both amine enantiomers with high purity and significant amounts.
Area of Science:
- Organic Chemistry
- Biocatalysis
- Asymmetric Synthesis
Background:
- Chiral secondary amines are crucial building blocks in pharmaceuticals and fine chemicals.
- Developing efficient and scalable methods for their enantioselective synthesis remains a significant challenge in organic chemistry.
Purpose of the Study:
- To develop a practical and efficient chemoenzymatic method for the preparation of enantiomerically pure secondary amines.
- To explore the utility of oxalamic esters in enzyme-catalyzed kinetic resolution of racemic secondary amines.
Main Methods:
- Enzyme-catalyzed kinetic resolution of racemic secondary amines via derivatization with oxalamic esters.
- Utilizing specific enzymes to selectively react with one enantiomer of the derivatized amine.
- Cleavage of the oxalamic groups to liberate the free chiral amines.
Main Results:
- Successful preparation of a variety of chiral secondary amines with high optical purity.
- Achieved high yields for both enantiomers of the target amines.
- Demonstrated the efficiency and practicality of the developed chemoenzymatic method.
Conclusions:
- The developed chemoenzymatic strategy offers an effective route to access enantiopure secondary amines.
- Oxalamic esters are suitable substrates for enzyme-catalyzed kinetic resolution, enabling access to both amine enantiomers.
- This method provides a valuable tool for the synthesis of chiral amines in organic chemistry and drug discovery.
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