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Palladium-Catalyzed Enantioselective Intermolecular Coupling of Phenols and Allylic Alcohols.

ABSTRACT: An enantioselective intermolecular coupling of oxygen nucleophiles and allylic alcohols to give ?-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 ?-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.

SUBMITTER: Race NJ

PROVIDER: S-EPMC5180452 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Palladium-Catalyzed Enantioselective Intermolecular Coupling of Phenols and Allylic Alcohols.

Race Nicholas J NJ Schwalm Cristiane S CS Nakamuro Takayuki T Sigman Matthew S MS

Journal of the American Chemical Society 20161201 49

An enantioselective intermolecular coupling of oxygen nucleophiles and allylic alcohols to give β-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 β-hydride elimination toward the adjacent alcohol. Deuterium labeling experiments suggest a syn-migratory insertion of the alkene into the Pd-O bond. A broad scop ...[more]

PMID: 27960316

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