Organocatalytic Multicomponent Domino Asymmetric Reactions

SCHEME 2.23 Asymmetric synthesis of spiro[5,5]undecane-l,5,9-trione derivatives 87. 

SCHEME 2.24 Three-component synthesis of 3-amino-6-lactams via a formal [4+2] cycloaddition reaction. 

Prompted by the groundbreaking work of Enders [52], who outstandingly disclosed the potential of organocatalysis toward the straightforward consti uction of complex molecules in just one-pot procedure, a wider and wider segment of organic chemists have been involved in the improvement and 

The second subsection (Section 2.4.2) deals with selected examples of other multicomponent tandem or domino-type reactions, which should be mentioned for their synthetic interest. Moreover, since the high value of several developed 

1 Double Cascade Reactions Starting with the double cascade reactions, Gong et al. reported a straightforward access to enantiomerically enriched dihydropyridines by means of an asymmetric three-component cyclization 

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A. Carlone, S. Cabrera, M. Marigo, K. A. Jprgensen, Angew. Chem. Int. Ed. 2007, 46, 1101-1104. A new approach for an organocatalytic multicomponent domino asymmetric reaction. 

Combinations of enamine-iminium ion activations together with other organo-catalytic activations in asymmetric organocatalytic domino and multicomponent reactions have been developed to achieve the enantioselective consecutive formation of two or more bonds in a stereoselective fashion. 

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