Asymmetric aminocatalysis

List B (2000) The direct catalytic asymmetric three-component Mannich reaction. J Am Chem Soc 122 9336-9337 ListB (2001) Asymmetric aminocatalysis. Synlett 2001 1675-1686 List B (2002a) Direct catalytic asymmetric alpha-amination of aldehydes. J Am Chem Soc 124 5656-5657... 

List B. Asymmetric aminocatalysis. Synlett 2001 1675-1686. Notz W, Tanaka F, Barbas III CF. Enamine-based organocatalysis with proline and diamines the development of direct catalytic asymmetric aldol, Mannich, Michael, and Diels-Alder reactions. Acc. Chem. Res. 2004 37 580-591. 

B. List, The Ying and Yang of Organic Asymmetric Aminocatalysis, J Chem Soc, Chem Commun 819 2006. 

The asymmetric a-allqrlation of carbonyl compounds constitutes one of the fundamental organic transformations for the construction of carbon-carbon bonds, and has long been the Achilles heel for asymmetric aminocatalysis. Towards a solution to this long-standing problem, Jacobsen and coworkers have shown that the enantioselective a-allqrlation of a-arylpropionaldehydes with diarylbromonethane can be carried out under the catalysis of primary-amine thiourea 39 (Scheme 19.60). Catalyst 39 reacted with the aldehyde to form an enamine, followed by a S -l-type substitution induced by the bromide anion. 

The term aminocatalysis has been coined [4] to designate reactions catalyzed by secondary and primary amines, taking place via enamine and iminium ion intermediates. The field of asymmetric aminocatalysis, initiated both by Hajos and Parrish [5] and by Eder, Sauer, and Wiechert [6] in 1971, has experienced a tremendous renaissance in the past decade [7], triggered by the simultaneous discovery of proline-catalyzed intermolecular aldol [8] and Mannich [9] reactions and of asymmetric Diels-Alder reactions catalyzed by chiral imidazolidinones [10]. Asymmetric enamine and iminium catalysis have been influential in creating the field of asymmetric organocatalysis [11], and probably for this reason aminocatalytic processes have been the object of the majority of mechanistic smdies in organocatalysis. 

Iminium Catalysis. Together with enamine catalysis, iminium catalysis is the most prominent activation mode in asymmetric aminocatalysis [61]. Initial work was carried out on cycloadditions [10, 62], but it was rapidly extended to... 

Covalent Modes of Catalysis-Developing MCRs by Asymmetric Aminocatalysis 11287... 

The feasibihty of this aminocatalytic strategy, which combines two intermohcular and stereoselective bond-forming events, was independently established in 2005 by two research groups, those of Jorgensen [32] and MacMillan [33]. It has become common for challenging concepts in asymmetric aminocatalysis to be developed independently (and almost simultaneously) by different research groups. This accounts for the tremendous scientific competition, which has led to excellent levels of development and innovation in the field [34]. 

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