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Ligand-Enabled, Palladium-Catalyzed ?-C(sp3)-H Arylation of Weinreb Amides.

ABSTRACT: We report the development of Pd(II)-catalyzed C(sp3)-H arylation of Weinreb amides. This work demonstrates the first example of using Weinreb amide as a directing group for transition metal-catalyzed C(sp3)-H activation. Both the inductive effect and the potential bidentate coordination mode of the Weinreb amides pose a unique challenge for this reaction development. A pyridinesulfonic acid ligand is designed to accommodate the weak, neutral coordinating property of Weinreb amides via preserving the cationic character of Pd center through zwitterionic assembly of Pd/ligand complexes. DFT studies of the C-H cleavage step indicate that the superior reactivity of 3-pyridinesulfonic acid ligand compared to pyridine, Ac-Gly-OH, and ligandless conditions originates from the stabilization of overall substrate-bound Pd species.

SUBMITTER: Park H

PROVIDER: S-EPMC6586421 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Ligand-Enabled, Palladium-Catalyzed β-C(sp3)-H Arylation of Weinreb Amides.

Park Hojoon H Chekshin Nikita N Shen Peng-Xiang PX Yu Jin-Quan JQ

ACS catalysis 20180905 10

We report the development of Pd(II)-catalyzed C(sp3)-H arylation of Weinreb amides. This work demonstrates the first example of using Weinreb amide as a directing group for transition metal-catalyzed C(sp3)-H activation. Both the inductive effect and the potential bidentate coordination mode of the Weinreb amides pose a unique challenge for this reaction development. A pyridinesulfonic acid ligand is designed to accommodate the weak, neutral coordinating property of Weinreb ...[more]

PMID: 31223513

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