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Catalytic (3 + 2) annulation of donor-acceptor aminocyclopropane monoesters and indoles.

ABSTRACT: The efficient catalytic activation of donor-acceptor aminocyclopropanes lacking the commonly used diester acceptor is reported here in a (3 + 2) dearomative annulation with indoles. Bench-stable tosyl-protected aminocyclopropyl esters were converted into cycloadducts in 46-95% yields and up to 95 : 5 diastereomeric ratio using catalytic amounts of triethylsilyl triflimide. Tricyclic indoline frameworks containing four stereogenic centers including all-carbon quaternary centers were obtained.

SUBMITTER: Pirenne V

PROVIDER: S-EPMC8246098 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Catalytic (3 + 2) annulation of donor-acceptor aminocyclopropane monoesters and indoles.

Pirenne Vincent V Robert Emma G L EGL Waser Jerome J

Chemical science 20210505 25

The efficient catalytic activation of donor-acceptor aminocyclopropanes lacking the commonly used diester acceptor is reported here in a (3 + 2) dearomative annulation with indoles. Bench-stable tosyl-protected aminocyclopropyl esters were converted into cycloadducts in 46-95% yields and up to 95 : 5 diastereomeric ratio using catalytic amounts of triethylsilyl triflimide. Tricyclic indoline frameworks containing four stereogenic centers including all-carbon quaternary centers were obtained. ...[more]

PMID: 34257869

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