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Organocatalysis in Cross-Coupling: DMEDA-Catalyzed Direct C-H Arylation of Unactivated Benzene.

06:00 EDT 4th August 2010 | BioPortfolio

Summary of "Organocatalysis in Cross-Coupling: DMEDA-Catalyzed Direct C-H Arylation of Unactivated Benzene."

A striking breakthrough to the frame of traditional cross-couplings/C-H functionalizations using an organocatalyst remains unprecedented. We uncovered a conceptually different approach toward the biaryl syntheses by using DMEDA as the catalyst to promote the direct C-H arylation of unactivated benzene in the presence of potassium tert-butoxide. The arylation of unactivated benzene with aryl iodides, or aryl bromides and even chlorides under the assistance of an iodo-group, could simply take place at 80 degrees C. The new methodology presumably involves an aryl radical anion as an intermediate. This finding offers an option toward establishing a new horizon for direct C-H/cross-coupling reactions.

Affiliation

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei, P. R. China, 430072, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai, 200032, P.

Journal Details

This article was published in the following journal.

Name: Journal of the American Chemical Society
ISSN: 1520-5126
Pages:

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