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Directed oxidative cyclizations to C2- or C4-positions of indole: efficient construction of the bicyclo[4.3.1]decane core of welwitindolinones.

ABSTRACT: Regiocontrolled oxidative cyclizations of 3-substituted indoles are described herein. Specifically, it is shown that the installation of a chloride at C2 alters the inherent propensity for cyclization at the 2-position of indole so as to favor the 4-position, enabling the construction of the unique framework found in most welwitindolinone alkaloids. The chloride functions here as more than a blocking group, as it also provides ready access to the corresponding oxindole.

SUBMITTER: Bhat V

PROVIDER: S-EPMC3368440 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Directed oxidative cyclizations to C2- or C4-positions of indole: efficient construction of the bicyclo[4.3.1]decane core of welwitindolinones.

Bhat Vikram V Mackay James A JA Rawal Viresh H VH

Organic letters 20110526 12

Regiocontrolled oxidative cyclizations of 3-substituted indoles are described herein. Specifically, it is shown that the installation of a chloride at C2 alters the inherent propensity for cyclization at the 2-position of indole so as to favor the 4-position, enabling the construction of the unique framework found in most welwitindolinone alkaloids. The chloride functions here as more than a blocking group, as it also provides ready access to the corresponding oxindole. ...[more]

PMID: 21615098

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