Journal of the American Chemical Society, Vol.138, No.49, 15881-15884, 2016
Palladium-Catalyzed Enantioselective Intermolecular Coupling of Phenols and Allylic Alcohols
An enantioselective intermolecular coupling of oxygen nucleophiles and allylic alcohols to give beta-aryloxycarbonyl compounds is disclosed using a chiral pyridine oxazoline-ligated palladium catalyst under mild conditions. As opposed to the formation of traditional Wacker-type products, enantioselective migratory insertion is followed by beta-hydride elimination toward the adjacent alcohol. Deuterium labeling experiments suggest a syn-migratory insertion of the alkene into the Pd-O bond. A broad scope of phenols, various allylic alcohols, and an alkyl hydroperoxide are viable coupling partners in this process.