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Synthesis of indoles via 6pi-electrocyclic ring closures of trienecarbamates.

ABSTRACT: A new method for the preparation of indoles from readily available alpha-haloenones and alpha-(trialkylstannyl)enecarbamates is described. Following a Stille coupling, trienecarbamate 2 is electronically activated to undergo a facile 6pi-electrocyclic ring closure and subsequent oxidation to afford protected aniline 4. Upon deprotection and reductive amination, acid 5 underwent clean cyclization to N-acetylindole 6 (Ac2O, NEt3, 130 degrees C). This method has been used to construct a variety of substituted indoles that are not easily prepared by conventional indole annelation methods.

SUBMITTER: Greshock TJ

PROVIDER: S-EPMC2597544 | biostudies-other | 2006 Apr

REPOSITORIES: biostudies-other

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Synthesis of indoles via 6pi-electrocyclic ring closures of trienecarbamates.

Greshock Thomas J TJ Funk Raymond L RL

Journal of the American Chemical Society 20060401 15

A new method for the preparation of indoles from readily available alpha-haloenones and alpha-(trialkylstannyl)enecarbamates is described. Following a Stille coupling, trienecarbamate 2 is electronically activated to undergo a facile 6pi-electrocyclic ring closure and subsequent oxidation to afford protected aniline 4. Upon deprotection and reductive amination, acid 5 underwent clean cyclization to N-acetylindole 6 (Ac2O, NEt3, 130 degrees C). This method has been used to construct a variety of ...[more]

PMID: 16608316

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