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A General and Practical Palladium-Catalyzed Direct ?-Arylation of Amides with Aryl Halides.

ABSTRACT: An efficient system for the direct catalytic intermolecular ?-arylation of acetamide derivatives with aryl bromides and chlorides is presented. The palladium catalyst is supported by Kwong's indole-based phosphine ligand and provides monoarylated amides in up to 95% yield. Excellent chemoselectivities (>10:1) in the mono- and diarylation with aryl bromides were achieved by careful selection of bases, solvents, and stoichiometry. Under the coupling conditions, the weakly acidic ?-protons of amides (pKa up to 35) were reversibly depotonated by LiO t Bu, NaO t Bu, or NaN(SiMe3)2.

SUBMITTER: Zheng B

PROVIDER: S-EPMC3994175 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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A General and Practical Palladium-Catalyzed Direct α-Arylation of Amides with Aryl Halides.

Zheng Bing B Jia Tiezheng T Walsh Patrick J PJ

Advanced synthesis & catalysis 20140101 1

An efficient system for the direct catalytic intermolecular α-arylation of acetamide derivatives with aryl bromides and chlorides is presented. The palladium catalyst is supported by Kwong's indole-based phosphine ligand and provides monoarylated amides in up to 95% yield. Excellent chemoselectivities (>10:1) in the mono- and diarylation with aryl bromides were achieved by careful selection of bases, solvents, and stoichiometry. Under the coupling conditions, the weakly acidic α-protons of amide ...[more]

PMID: 24765060

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