O-1-(1,3-butadienyl) carbamates as diels-alder dienes: Stereospecific synthesis of (±)-Hernandulcin and congeners

Article abstract of DOI:10.1016/S0040-4039(00)88818-8

The TiCl₄-catalyzed addition of the title reactants to vinyl ketones regio- and stereospecifically yields cis-disubs, cyclohexenes which add RMgX stereospecifically to the ketone. A final product in this sequence is the intensely sweet sesquiterpene, hernandulcin.