Improvement of Kinetic Resolution Processes

There are several ways to optimize the transformation of a racemic substrate into an enantioenriched recovered starting material or product. For example, the process of 

There is the possibility to combine several KR reactions and to approach the theoretical maximum values of 50% recovery and 100% ee for one of the enantiomers. This can be achieved after isolation of the components of a first KR [30]. Consecutive KRs will also enhance the enantiomeric excess [31]. The amount of recovered material will decrease. KR has been used to increase the enantiomeric excess of an aheady enantioenriched material (obtained by KR or asymmetric synthesis). The conversion extent needed for going from 90% to 95% ee, for example, for a given s value, has been calculated for pseudo-first-order reactions [23]. Enantioconvergent reactions (see below. Section 2.5) is a rare but convenient way to optimize a KR from a racemic mixture where the enantiomers are susceptible to interconversion. 

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