Asymmetric catalysis dynamic kinetic resolution

Mechanisms with a common catalyst are typical for synthesis of regio-isomers in addition reactions, in asymmetric catalysis, dynamic kinetic resolution and a number of other reactions (Fig. 5.34). 

Asymmetric Transformations by Coupled Enzyme and Metal Catalysis Dynamic Kinetic Resolution... 

Huerta FF, Minidis ABE, Backvall JE (2001) Racemisation in asymmetric synthesis. Dynamic kinetic resolution and related processes in enzyme and metal catalysis. Chem Soc Rev 30 321-331... 

Pellissier, H., Recent developments in dynamic kinetic resolution. Tetrahedron, 2008, 64, 1563-1601 Turner, N.J., Enzyme catalysed deracemisation and dynamic kinetic resolution reactions. Curr. Opin. Chem. Biol., 2004, 8, 114-119 Gmber, C.C., Lavandera, I., Faber, K. and Kroutil, W., From a racemate to a single enantiomer deracemisation by stereoinversion. Adv. Synth. Catal., 2006, 348, 1789-1805 Pellissier, H., Dynamic kinetic resolution. Tetrahedron, 2003, 59, 8291-8327 Pmnies, O. and Backvall, J.-E., Combination of enzymes and metal catalysts. A powerful approach in asymmetric catalysis. Chem. Rev., 2003, 103, 3247-3261. 

M. J. Kim, Y. Ahn, and J. Park, Dynamic kinetic resolutions and asymmetric transformations by enzymes couples with metal catalysis, Curr. Opin. Biotechnol. 2002, 13, 578-587. 

Notz W, Tanaka F, Watanabe S, Chaudari NS, Turner JM, Thayumanavan R, Barbas CF 3rd (2003) The direct organocatalytic asymmetric mannich reaction unmodified aldehydes as nucleophiles. J Org Chem 68 9624-9634 Noyori R (2002) Asymmetric catalysis science and opportunities (Nobel lecture). Angew Chem Int Ed Engl 41 2008-2022 Noyori R, Tokunaga M, Kitamura M (1995) Stereoselective organic synthesis via dynamic kinetic resolution. Bull Chem Soc Jpn 68 36-55 Ohkuma T, Kitamura M, Noyori R (2000) Asymmetric hydrogenation. In Ojima I (ed) Catalytic asymmetric synthesis, 2nd edn. Wiley-VCH, New York, p 1-110... 

Vongvilai P, Larsson R, Ramstrom O (2008) Direct asymmetric dynamic kinetic resolution by combined lipase catalysis and nitroaldol (Henry) reaction. Adv Synth Catal 350 448 152... 

Asymmetric catalysis may also be achieved by the kinetic resolution of racemic substrates, where one enantiomer of starting material is selectively converted into product, leaving the other enantiomer unreacted, in some instances, both enantiomers of a starting material are converted into the same enantiomer of product, i.e. dynamic kinetic resolution. Most reactions fit into one of the categories identified in Figures 1.1-1.3, even if the exact structure is not represented. 

The asymmetric processes discussed so far in this chapter have focused on reactions that create non-racemic, chiral products from achiral reagents by selective reaction at one prochiral face or position over the other. However, these principles can also be applied to reactions that separate enantiomers of an existing racemic mixture, channel both enantiomers of such a mixture to a single enantiomeric product, or that select between reaction at one of two diastereotopic functional groups in an achiral substrate. These reactions are also synthetically valuable and are called kinetic resolutions, dynamic kinetic resolutions, and desymmetrizations. An understanding of these reactions draws from the principles established so far in this chapter, but they also require some additional principles to be established that apply in a specific way to these classes of asymmetric transformations. Thus, the remainder of Chapter 14 introduces the fundamentals of these classes of asymmetric catalysis. 

Backvall JE (2006) Asymmetric catalysis via dynamic kinetic resolution. In Christmann M, Erase S (eds) Asymmetric synthesis - the essentials. Wiley-VCH, Weinheim... 

Blum, P., and Berkowitz, D.B. (2010) Use of a robust dehydrogenase from an archael hyperthermophile in asymmetric catalysis-dynamic reductive kinetic resolution entry into (S)-profens. J. Am. Chem. Soc., 132, 5930-5931. 

Kejrwords Dynamic kinetic asymmetric transformation (DYKAT) Dynamic kinetic resolution (DKR) Hydrogenation Imine reduction Ketone reduction Mechanism of carbonyl reduction Mechanism of imine reduction Mechanism of dUiydrogen activation Ruthenium catalysis Shvo s catalyst Transfer hydrogenation... 

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