Catalysts in asymmetric synthesis

New Chiral Organophosphorus Catalysts in Asymmetric Synthesis J.-M. Brunei G. Buono... 

The cyclooctapyrroles shown in Figure 55 appear predestined to form binuclear metal complexes since the loop-shaped conformation of these macrocycles exhibits two structurally identical, helical N4 cavities. Enantiomers of such complexes, which are presumably generally very stable towards racemization owing to the rigidity of the molecule imposed by the incorporation of the metal, are of interest as possible models for binuclear metalloenzymes and as potential catalysts in asymmetric synthesis. The first two ligands as well as their recently obtained palladium complexes601 were... 

High-Loading Dendritic Catalysts in Asymmetric Synthesis ... 

M. G. Finn, K. B, Sharpless, Epoxidation with Titanium-Tartrate Catalysts in Asymmetric Synthesis, J. D. Morrison, Ed.. Vol. 5, pp 269-271, Academic, New York 1985. 

M. J. Porter S. M. Roberts, and J. Skidmore, Polyamino acids as catalysts in asymmetric synthesis, Bioorgan. Med. 

A further application of L-proline as a catalyst in asymmetric synthesis, which was found by List, is the three-component-Mannich reaction for the preparation of /1-amino ketones [12]. In the presence of L-proline as a catalyst the Mannich product 6 has been obtained in 50% yield and with 94% ee (Scheme 5, reaction 1). 

I Simple Amino Acids and Short-chain Peptides as Efficient Metal-free Catalysts in Asymmetric Synthesis... 

Industry perspectives on the use of catalysts in asymmetric synthesis are Chemical and Engineering News, June 14 2004, pages 47-62, and September 5, 2005, pages 40-60. 

Ferrocenoyl chloride (318), ethyl ferrocenecarboxylate (319), and cyanoferrocene (320) are all used as starting materials for the synthesis of 2-ferrocenyloxazolines (321) (Scheme 87). Chirality may be incorporated into the oxazoline ring, and these important chiral compounds have been used to prepare a great number of ferrocene derivatives that are used as catalysts in asymmetric synthesis." " ... 

France S, Guerin DJ, Miller SJ, Leckta T. Nucleophilic chiral amines as catalysts in asymmetric synthesis. Chem. Rev. 2003 103 2985-3012. 

The potential of enzymes as catalysts in asymmetric synthesis has been recognised for many years.2-i2 Rate acceleration and stereoseiectivity, together with techniques for the iow-cost production and the rational alteration of their properties, make enzymes attractive as chiral catalysts in organic synthesis. Enzyme-catalyzed reactions have been categorised into six main groups ll as shown in Table 1. Three of them, oxido-reductases, hydrolases, and lyases have been found useful in organic synthesis. 

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