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Catalytic enantioselective alkenylation-heteroarylation of olefins: stereoselective syntheses of 5-7 membered azacycles and oxacycles.

ABSTRACT: Catalytic enantioselective domino alkenylation-heteroarylation of nonconjugated iododienes proceeded with excellent stereoselectivity and broad scope of substrates. The reaction enables stereoselective syntheses of substituted azacycles such as piperidine, pyrrolidine azepine and dihydropyrans carrying new quaternary stereocenters. Mechanistically, C-H bonds of heterocycles were activated by lithium alkoxides via reversible deprotonation, rather than conventional palladium(ii)-assisted metalation processes. Many types of heteroarenes can be used, including not only azoles (such as thiazoles, oxazoles, imidazoles and oxadiazoles), but also nonazoles (thiophene, furan and azine N-oxides).

SUBMITTER: Ma Z

PROVIDER: S-EPMC10016361 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Catalytic enantioselective alkenylation-heteroarylation of olefins: stereoselective syntheses of 5-7 membered azacycles and oxacycles.

Ma Zhaoming Z Sun Lantian L Zhou Jianrong Steve JS

Chemical science 20230217 11

Catalytic enantioselective domino alkenylation-heteroarylation of nonconjugated iododienes proceeded with excellent stereoselectivity and broad scope of substrates. The reaction enables stereoselective syntheses of substituted azacycles such as piperidine, pyrrolidine azepine and dihydropyrans carrying new quaternary stereocenters. Mechanistically, C-H bonds of heterocycles were activated by lithium alkoxides via reversible deprotonation, rather than conventional palladium(ii)-assisted me ...[more]

PMID: 36937582

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