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Orthogonal Pd- and Cu-based catalyst systems for C- and N-arylation of oxindoles.

ABSTRACT: In the cross-coupling reactions of unprotected oxindoles with aryl halides, Pd- and Cu-based catalyst systems displayed orthogonal chemoselectivity. A Pd-dialkylbiarylphosphine-based catalyst system chemoselectively arylated oxindole at the 3 position, while arylation occurred exclusively at the nitrogen using a Cu-diamine-based catalyst system. Computational examination of the relevant L1Pd(Ar)(oxindolate) and diamine-Cu(oxindolate) species was performed to gain mechanistic insight into the controlling features of the observed chemoselectivity.

SUBMITTER: Altman RA

PROVIDER: S-EPMC2587375 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Orthogonal Pd- and Cu-based catalyst systems for C- and N-arylation of oxindoles.

Altman Ryan A RA Hyde Alan M AM Huang Xiaohua X Buchwald Stephen L SL

Journal of the American Chemical Society 20080628 29

In the cross-coupling reactions of unprotected oxindoles with aryl halides, Pd- and Cu-based catalyst systems displayed orthogonal chemoselectivity. A Pd-dialkylbiarylphosphine-based catalyst system chemoselectively arylated oxindole at the 3 position, while arylation occurred exclusively at the nitrogen using a Cu-diamine-based catalyst system. Computational examination of the relevant L1Pd(Ar)(oxindolate) and diamine-Cu(oxindolate) species was performed to gain mechanistic insight into the con ...[more]

PMID: 18588302

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