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Asymmetric α-spirocyclopropanation of oxindoles and benzofuranones via dynamic kinetic resolution.

ABSTRACT: Chiral benzo five-membered heterocyclic spirocyclopropanes are an important class of parent core structures with pharmacological activity. A novel organocatalytic one-pot cascade ether oxidation iminium-ion activation strategy for the asymmetric spirocyclopropylation of benzofuran-2-ones and indolin-2-ones from allyl tert-butyl ethers/ pent-2,4-dienyl ethyl ethers with excellent enantioselectivity (ee% up to > 99) and diastereoselectivity(dr.% up to 91:9) has been developed. This process involves the successful dynamic kinetic resolution of racemic 3-bromobenzofuran-2-ones or 3-bromoindolin-2-ones. Its synthetic application will provide a new aminocatalytic cascade tool for the efficient synthesis of complex molecules.

SUBMITTER: Hu Y

PROVIDER: S-EPMC9814566 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Asymmetric α-spirocyclopropanation of oxindoles and benzofuranones via dynamic kinetic resolution.

Hu Yang Y Yuan Jie J Li Zheyao Z Zhao Lin L Zhao Jianhong J Yu Xinhong X

Communications chemistry 20220906 1

Chiral benzo five-membered heterocyclic spirocyclopropanes are an important class of parent core structures with pharmacological activity. A novel organocatalytic one-pot cascade ether oxidation iminium-ion activation strategy for the asymmetric spirocyclopropylation of benzofuran-2-ones and indolin-2-ones from allyl tert-butyl ethers/ pent-2,4-dienyl ethyl ethers with excellent enantioselectivity (ee% up to > 99) and diastereoselectivity(dr.% up to 91:9) has been developed. This process involve ...[more]

PMID: 36697948

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