A sulfinyl trialkoxycarbonyl ethene as a new enantiopure dienophile in asymmetric diels-alder reactions

Abstract The synthesis and the asymmetric Diels-Alder reactions of the enantiomerically pure ( S )- p -tolylsulfinyl trialkoxycarbonyl ethene 3 with cyclic and acyclic dienes are reported. π-Facial selectivity and regioselectivity are very high in all studied cases. Reactions with cyclopentadiene exhibit moderated or high exo -selectivity, which disappears with acyclic dienes. The use of high pressure improves the π-facial selectivity but does not substantially modify the endo-exo selectivity.