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Benzannulation via the reaction of ynamides and vinylketenes. application to the synthesis of highly substituted indoles.

ABSTRACT: A two-stage "tandem strategy" for the synthesis of indoles with a high level of substitution on the six-membered ring is described. Benzannulation based on the reaction of cyclobutenones with ynamides proceeds via a cascade of four pericyclic reactions to produce multiply substituted aniline derivatives in which the position ortho to the nitrogen can bear a wide range of functionalized substituents. In the second stage of the tandem strategy, highly substituted indoles are generated via acid-, base-, and palladium-catalyzed cyclization and annulation processes.

SUBMITTER: Lam TY

PROVIDER: S-EPMC3832264 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Benzannulation via the reaction of ynamides and vinylketenes. application to the synthesis of highly substituted indoles.

Lam Tin Yiu TY Wang Yu-Pu YP Danheiser Rick L RL

The Journal of organic chemistry 20130903 18

A two-stage "tandem strategy" for the synthesis of indoles with a high level of substitution on the six-membered ring is described. Benzannulation based on the reaction of cyclobutenones with ynamides proceeds via a cascade of four pericyclic reactions to produce multiply substituted aniline derivatives in which the position ortho to the nitrogen can bear a wide range of functionalized substituents. In the second stage of the tandem strategy, highly substituted indoles are generated via acid-, b ...[more]

PMID: 23952525

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