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Synthetic Studies toward the Hamigerans with a 6-7-5 Tricyclic Core.

ABSTRACT: An approach toward the 6-7-5 tricyclic carbon skeleton of the hamigeran natural products was developed. The key steps include a benzyne-β-ketoester annulative ring expansion to form the 7-membered ring, a Nazarov reaction to form the 5-membered ring, a Ni-catalyzed conjugate methyl addition or a Corey-Chaykovsky reaction to install the all-carbon quaternary center, and a Suzuki cross coupling followed by reduction to introduce the isopropyl group.

SUBMITTER: Jiang B

PROVIDER: S-EPMC8232352 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Synthetic Studies toward the Hamigerans with a 6-7-5 Tricyclic Core.

Jiang Baiyang B Dai Mingji M

Organic letters 20200513 11

An approach toward the 6-7-5 tricyclic carbon skeleton of the hamigeran natural products was developed. The key steps include a benzyne-β-ketoester annulative ring expansion to form the 7-membered ring, a Nazarov reaction to form the 5-membered ring, a Ni-catalyzed conjugate methyl addition or a Corey-Chaykovsky reaction to install the all-carbon quaternary center, and a Suzuki cross coupling followed by reduction to introduce the isopropyl group. ...[more]

PMID: 32401527

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