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Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
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Chiroptical Asymmetric Reaction Screening via Multicomponent Self-Assembly
Zeus A De Los Santos1, Christian Wolf1
1Department of Chemistry, Georgetown University , Washington, D.C. 20057, United States.
Journal of the American Chemical Society
|October 5, 2016
Summary
A new chiroptical sensing method uses palladium and chiral ligands to analyze stereochemistry. This mix-and-measure technique efficiently determines the configuration, enantiomeric excess, and yield of amines with minimal sample.
Area of Science:
- Coordination chemistry
- Analytical chemistry
- Organic synthesis
Background:
- Chiral molecules are crucial in pharmaceuticals and materials science.
- Accurate determination of stereochemistry (absolute configuration, enantiomeric excess) is vital.
- Existing methods for stereochemical analysis can be time-consuming and resource-intensive.
Purpose of the Study:
- To develop a rapid and efficient method for quantitative stereochemical analysis.
- To establish a mix-and-measure protocol for determining the absolute configuration, enantiomeric excess (ee), and yield of chiral amines.
- To minimize sample consumption, cost, labor, and waste in stereochemical analysis.
Main Methods:
- Self-assembly of a stereodynamic phosphine ligand, Palladium(II) (Pd(II)), and a chiral substrate (amine, amino alcohol, or amino acid).
- Utilizing characteristic ultraviolet (UV) and circular dichroism (CD) signals generated during self-assembly for analysis.
- Application of a robust mix-and-measure chiroptical sensing protocol.
Main Results:
- The developed protocol generates distinct UV and CD signals upon self-assembly, enabling quantitative analysis.
- The method successfully determined the absolute configuration, ee, and yield of an amine produced via iridium-catalyzed asymmetric hydrogenation of an iminium salt.
- The analysis requires only 1 mg of the crude reaction mixture, demonstrating high sensitivity and efficiency.
Conclusions:
- A novel and robust chiroptical sensing protocol has been established for the quantitative stereochemical analysis of chiral amines.
- This method offers a significant advantage by requiring minimal sample amounts (1 mg) and reducing overall analysis time and resources.
- The protocol provides a valuable tool for efficient characterization in asymmetric synthesis and related fields.
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