title: A catalytic, enantioselective formal synthesis of (+)-dichroanone and (+)-taiwaniaquinone H.
abstract: A catalytic, enantioselective formal synthesis of (+)-dichroanone and (+)-taiwaniaquinone H is reported. The all-carbon quaternary stereocenter was constructed by asymmetric conjugate addition catalyzed by a palladium(II) (S)-tert-butylpyridinooxazoline complex. The unexpected formation of a [3.2.1] bicyclic intermediate required the identification of a new route. Analysis of the Hammett constants for para-substituted arenes enabled the rational design of a highly enantioselective conjugate addition substrate that led to the completion of the formal synthesis.
authors.affiliation: The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , 1200 East California Boulevard, MC 101-20, Pasadena, California 91125, United States.
authors.forename: Samantha E
authors.initials: SE
authors.lastname: Shockley
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Holder
authors.forename: Brian M
authors.initials: BM
authors.lastname: Stoltz
mesh_terms: D002384:Catalysis; D004224:Diterpenes / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D004224:Diterpenes; C516091:dichroanone; C516088:taiwaniaquinone H; D010165:Palladium