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A new route to ?-carbolines based on 6?-electrocyclization of indole-3-alkenyl oximes.

ABSTRACT: Indoles are converted into ?-carbolines in four steps by acylation at C-3, Boc-protection, olefination of the resulting 3-indolyl aldehydes or ketones to give N-Boc-3-indolyl alkenyl oxime O-methyl ethers, which upon heating to 240 °C under microwave irradiation undergo loss of the Boc-group, and 6?-electrocyclization to ?-carbolines, following aromatization by loss of methanol (11 examples, 30-90% yield).

SUBMITTER: Markey SJ

PROVIDER: S-EPMC3971735 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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A new route to α-carbolines based on 6π-electrocyclization of indole-3-alkenyl oximes.

Markey Sophie J SJ Lewis William W Moody Christopher J CJ

Organic letters 20131126 24

Indoles are converted into α-carbolines in four steps by acylation at C-3, Boc-protection, olefination of the resulting 3-indolyl aldehydes or ketones to give N-Boc-3-indolyl alkenyl oxime O-methyl ethers, which upon heating to 240 °C under microwave irradiation undergo loss of the Boc-group, and 6π-electrocyclization to α-carbolines, following aromatization by loss of methanol (11 examples, 30-90% yield). ...[more]

PMID: 24280001

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