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Updated: Aug 8, 2026
07:06
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Asymmetric amplification by kinetic resolution using a racemic reagent: example in amine acetylation
Tummanapalli Satyanarayana1, Henri B Kagan
1Laboratoire de Catalyse Moléculaire, UMR 8075, Institut de Chimie Moléculaire et des Matériaux d'Orsay, Université Paris-Sud, 91405 Orsay, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|May 17, 2006
Summary
This study demonstrates significant asymmetric amplification in amine acylation, enhancing enantiomeric excess (ee) from low levels to over 95%. Sequential amplifications achieved a remarkable 97% ee starting from just 1.5% ee.
Area of Science:
- Organic Chemistry
- Asymmetric Synthesis
- Chiral Chemistry
Background:
- Enantiomeric excess (ee) is crucial for chiral compound efficacy.
- Achieving high ee from low initial values presents a significant synthetic challenge.
Purpose of the Study:
- To investigate asymmetric amplification strategies for amine acylation.
- To explore the combination of sequential asymmetric amplifications for maximizing enantiomeric excess.
Main Methods:
- Studied the reaction of racemic reagents with enantiomeric mixtures.
- Employed sequential asymmetric amplification techniques, including those utilizing racemic reagents and positive nonlinear effects.
Main Results:
- Demonstrated substantial asymmetric amplification, increasing ee from 67% to over 95.5%.
- Achieved a final product with 97% ee through two sequential asymmetric amplifications, starting from 1.5% ee.
Conclusions:
- Asymmetric amplification is a viable strategy for enhancing enantiomeric excess in amine acylation.
- Sequential application of different asymmetric amplification methods can lead to exceptionally high enantiomeric excess.
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