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Organocatalytic asymmetric Michael addition of unprotected 3-substituted oxindoles to 1,4-naphthoquinone.

ABSTRACT: We reported the first example of organocatalytic Michael addition of unprotected 3-prochiral oxindoles 1 to 1,4-naphthoquinone. Quinidine derivative (DHQD)(2)PYR was found to be able to catalyze this reaction in up to 83% ee, with moderate to excellent yields. This method could be used for the synthesis of enantioenriched 3,3-diaryloxindoles, and the catalytic synthesis of which was unprecedented.

SUBMITTER: Yu JS

PROVIDER: S-EPMC3458762 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Organocatalytic asymmetric Michael addition of unprotected 3-substituted oxindoles to 1,4-naphthoquinone.

Yu Jin-Sheng JS Zhou Feng F Liu Yun-Lin YL Zhou Jian J

Beilstein journal of organic chemistry 20120823

We reported the first example of organocatalytic Michael addition of unprotected 3-prochiral oxindoles 1 to 1,4-naphthoquinone. Quinidine derivative (DHQD)(2)PYR was found to be able to catalyze this reaction in up to 83% ee, with moderate to excellent yields. This method could be used for the synthesis of enantioenriched 3,3-diaryloxindoles, and the catalytic synthesis of which was unprecedented. ...[more]

PMID: 23019472

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