Dynamic cyclic deracemization

Biocatalytic Deracemization Dynamic Resolution, Stereoinversion, Enantioconvergent Processes and Cyclic Deracemization, in Biocatalysts in the Pharmaceutical and Biotechnology industries, (ed. R.N. Patel), CRC Press, Boca Raton, pp. 27-51. 

During the past few years great efforts have been made to overcome the 50% threshold of enzyme-catalyzed KRs. Among the methods developed, deracemization processes have attracted considerable attention. Deracemizations are processes during which a racemate is converted into a non-racemic product in 100% theoretical yield without intermediate separation of materials [5]. This chapter aims to provide a summary of chemoenzymatic dynamic kinetic resolutions (DKRs) and chemoenzymatic cyclic deracemizations. 

It should be mentioned that the great majority of dynamic kinetic resolutions reported so far are carried out in organic solvents, whereas all cyclic deracemizations are conducted in aqueous media. Therefore, formally, this latter methodology would not fit the scope of this book, which is focused on the synthetic uses of enzymes in non-aqueous media. However, to fully present and discuss the applications and potentials of chemoenzymatic deracemization processes for the synthesis of enantiopure compounds, chemoenzymatic cyclic de-racemizations will also be briefly treated in this chapter, as well as a small number of other examples of enzymatic DKR performed in water. 

Simeo Y, KrontU W, Paber K. Biocatalytic deracemization dynamic resolution, stereoinversion, enantioconvergent processes, and cyclic deracemization. In Biocatalysis in the Pharmaceutical and Biotechnology Industries, Ed. Patel RN. CRC Press, Boca Raton, PL, 2007, p. 27. 

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