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Enantioselective addition of boronates to o-quinone methides catalyzed by chiral biphenols.

ABSTRACT: Chiral biphenols were found to catalyze the enantioselective asymmetric addition of aryl- or alkenylboronates to o-quinone methides. Substituted 2-styryl phenols were obtained in good yields (up to 95%) with high enantiomeric ratios (up to 98:2) in the presence of 10 mol % 3,3'-Br(2)-BINOL. A two-step synthesis of (S)-4-methoxydalbergione in good yield and selectivity was achieved.

SUBMITTER: Luan Y

PROVIDER: S-EPMC4655814 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Enantioselective addition of boronates to o-quinone methides catalyzed by chiral biphenols.

Luan Yi Y Schaus Scott E SE

Journal of the American Chemical Society 20121203 49

Chiral biphenols were found to catalyze the enantioselective asymmetric addition of aryl- or alkenylboronates to o-quinone methides. Substituted 2-styryl phenols were obtained in good yields (up to 95%) with high enantiomeric ratios (up to 98:2) in the presence of 10 mol % 3,3'-Br(2)-BINOL. A two-step synthesis of (S)-4-methoxydalbergione in good yield and selectivity was achieved. ...[more]

PMID: 23206197

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