Stoichiometric Kinetic Resolution Reactions

Mahagundappa R. Maddani, Jean-Qaude Fiaud, and Henri B. Kagan 

We published in 1988 an extended review article on the basis of KR and the main results [9]. A chapter is devoted to KR in the stereochemistry textbook by Eliel et al. [10]. Some recent reviews are available on various aspects of non-enzymatic KR [11], for example, practical considerations [12], metal-catalyzed KR processes (Chapter 3) [13], dynamic KR (Chapter 5) [14, 15], parallel KR 

Separation of Enantiomers Synthetic Methods, First Edition. Edited by Matthew Todd. 

This chapter focuses on stoichiometric KR reactions. In Section 2.2, the main kinetic treatments are discussed. In Section 2.3, some examples of the use of chiral reagents in KR are presented. In Sections 2.4 and 2.5, the cases of enantiodivergent and enantioconvergent reactions are discussed. The KR of diastereomers is kineti-caUy similar to KR of enantiomers and is briefly presented in Section 2.6. Finally, some examples of apphcations of KR are collected in Section 2.7. 

The expression KR emphasizes that the racemic mixture undergoes a separation under a chiral influence in a kinetically controlled process. In principle, the word resolution refers to the isolation of one of the enantiomers of racemic mixture after a partial transformation of the initial mixture. If the reaction product is chiral, as in the esterification of a racemic alcohol, then the KR will afford a product with some enantiomeric excess. The full transformation of a racemic mixture by coupling with a chiral auxiliary will give a 1 1 mixture of diastereomers and is not considered as a KR process, unless the reaction is stopped at an intermediate stage, leaving some enantioenriched starting material. 

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