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Synthesis of Carbazoles and Dihydrocarbazoles by a Divergent Cascade Reaction of Donor-Acceptor Cyclopropanes.

ABSTRACT: An alkylation/olefination cascade of indolecarboxaldehydes and phosphonate-functionalized donor-acceptor cyclopropanes affords functionalized dihydrocarbazoles and cyclohepta[cd]indoles in formal (3 + 3) and (4 + 3) cycloadditions. A minor modification to the reaction conditions also allows access to the fully aromatic heterocyclic scaffolds by thermal loss of an electron-rich aryl moiety.

SUBMITTER: Faltracco M

PROVIDER: S-EPMC8491164 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Synthesis of Carbazoles and Dihydrocarbazoles by a Divergent Cascade Reaction of Donor-Acceptor Cyclopropanes.

Faltracco Matteo M Damian Matteo M Ruijter Eelco E

Organic letters 20210920 19

An alkylation/olefination cascade of indolecarboxaldehydes and phosphonate-functionalized donor-acceptor cyclopropanes affords functionalized dihydrocarbazoles and cyclohepta[<i>cd</i>]indoles in formal (3 + 3) and (4 + 3) cycloadditions. A minor modification to the reaction conditions also allows access to the fully aromatic heterocyclic scaffolds by thermal loss of an electron-rich aryl moiety. ...[more]

PMID: 34543040

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