Application of D-chiro-inositol as a chiral template for the diels-alder reaction
Abstract
The Diels-Alder reaction can reliably provide the expected endo-product in the presence of secondary orbital overlap. It can be considerably more difficult to access a single enantiomer of the exo-product. In this paper, a D-chiro-inositol derivative is used as a chiral tether to facilitate the regio-, diastereo-, and enatioselective cycloaddition between cinnamic acid and hexa-3,5-dienoic acid. The Diels-Alder reaction between these two substrates, or their respective esters, does not occur under thermal conditions. Because of the ease of removal of the chiral tether from the resulting cyclohexene, this approach could provide a viable technique to access otherwise unavailable systems. Copyright © 2012 Verlag Helvetica Chimica Acta AG, Zürich, Switzerland.