Addition of Aldehydes and Ketones to Enones

When the donor and the acceptor of the conjugate addition are carbonyl compounds, the amine catalyst may activate both reagents, forming the iminium and enamine intermediates, respectively. The major mechanistic path is dictated by the structure of the substrates and catalyst and, to a lesser extent, by the reaction conditions. 

Professor Alexandre Alexakis is kindly acknowledged for the critical reading of the manuscript. 

1 For books and chapters, see (a) P. Perlmutter, Conjugate addition reactions in organic synthesis, 

Tomas sini, C. Chouillet, S. Roland, P. Mangeney, G. Bemardinelli, Angew. Chem. Int. Ed. 2000, 39, 4093-4095. 

20 Decreasing the reaction temperature results in an increase of the overall selectivity and a dramatic decrease in the conversion. 

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A novel antibody-catalysed intramolecular Michael addition of aldehydes and ketones to enones [(148) -> (149)] has been accomplished. The reaction is enantio- and diastereo-selective with a high ee and cis/trans ratio. Antibody 38C2 is the only catalyst to date capable of generating this selectivity in Michael addition products.177... 

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