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Vanadium-catalyzed regioselective oxidative coupling of 2-hydroxycarbazoles.

ABSTRACT: The first regioselective oxidative coupling of 2-hydroxycarbazoles is described. With a vanadium catalyst and oxygen as the terminal oxidant, dimers with an ortho-ortho' coupling pattern were obtained with high selectivity. Further oxidation led to ortho'-ortho' coupling to generate a tetramer, which provided insight that the atropisomerization barriers of the unsymmetrical biaryl bonds are much lower than expected.

SUBMITTER: Liu L

PROVIDER: S-EPMC4576935 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Vanadium-catalyzed regioselective oxidative coupling of 2-hydroxycarbazoles.

Liu Lei L Carroll Patrick J PJ Kozlowski Marisa C MC

Organic letters 20150115 3

The first regioselective oxidative coupling of 2-hydroxycarbazoles is described. With a vanadium catalyst and oxygen as the terminal oxidant, dimers with an ortho-ortho' coupling pattern were obtained with high selectivity. Further oxidation led to ortho'-ortho' coupling to generate a tetramer, which provided insight that the atropisomerization barriers of the unsymmetrical biaryl bonds are much lower than expected. ...[more]

PMID: 25590578

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