Synthesis of All-Carbon, Quaternary Center-Containing Cyclohexenones through an Organocatalyzed, Multicomponent Coupling

Organocatalyzed multicomponent coupling using a new ester-containing, proline aryl sulfonamide has been developed for accessing densely functionalized cyclohexenones, each containing a quaternary center in high enantio- and diastereoselectivity. In contrast to most enamine/iminium-catalyzed reactions, the use of molecular sieves was critical to optimum enantioselectivity.