Enantioselective separations by chromatographic methods can be achieved using two different experimental approaches . Firstly, diastereomeric derivatives are formed by reaction of a chiral compound with a chiral reagent. They may be separated on a stationary phase, which needs not necessarily be chiral. The advantage of this procedure is that a separation is possible with any chromatographic system as long as the required selectivity is available. The presence of at least one functional group as a site of reaction with an optically pure reagent is mandatory if the substrate is to be separated. One of the main drawbacks is the need to use optically pure reagents in order to avoid a systematic error. Another error may be introduced by the generation of energetically different (diastereomeric) transition states in the reaction of a mixture of enantiomers with a chiral reagent. Unless the reaction proceeds to completion, the different rates of these reactions may cause kinetic resolution and result in erroneous proportions of the product.
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- Enantioselective Chromatographic Methods for the Analysis of Chiral Environmental Pollutants
- Springer Berlin Heidelberg