(E)- and (Z)-Stereodefined Enol Sulfate Esters Derived from α-Aryl Aldehydes: Stereocomplementary Synthesis of Styryl Sulfate Natural Products.

A method for the stereoselective formation of enol sulfate esters from α-aryl aldehydes is described. This method involved the stereocontrolled enolization of a carbonyl group with DBU or t-BuOK followed by trapping with a reactive sulfuryl imidazolium salt, providing the corresponding styryl enol sulfate esters in good to excellent yields and stereoselectivities. This method was applied to the first total synthesis of the enol sulfate natural products in a stereocomplementary manner.