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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.

SUBMITTER: Shockley SE

PROVIDER: S-EPMC4275150 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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A catalytic, enantioselective formal synthesis of (+)-dichroanone and (+)-taiwaniaquinone H.

Shockley Samantha E SE Holder Jeffrey C JC Stoltz Brian M BM

Organic letters 20141209 24

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 addi ...[more]

PMID: 25489925

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