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Ligand-enabled ortho-C-H olefination of phenylacetic amides with unactivated alkenes.

ABSTRACT: Although chelation-assisted C-H olefination has been intensely investigated, Pd(ii)-catalyzed C-H olefination reactions are largely restricted to acrylates and styrenes. Here we report a quinoline-derived ligand that enables the Pd(ii)-catalyzed olefination of the C(sp2)-H bond with simple aliphatic alkenes using a weakly coordinating monodentate amide auxiliary. Oxygen is used as the terminal oxidant with catalytic copper as the co-oxidant. A variety of functional groups in the aliphatic alkenes are tolerated. Upon hydrogenation, the ortho-alkylated product can be accessed. The utility of this reaction is also demonstrated by the late-stage diversification of drug molecules.

SUBMITTER: Lu MZ

PROVIDER: S-EPMC5887099 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Ligand-enabled <i>ortho</i>-C-H olefination of phenylacetic amides with unactivated alkenes.

Lu Ming-Zhu MZ Chen Xing-Rong XR Xu Hui H Dai Hui-Xiong HX Yu Jin-Quan JQ

Chemical science 20171208 5

Although chelation-assisted C-H olefination has been intensely investigated, Pd(ii)-catalyzed C-H olefination reactions are largely restricted to acrylates and styrenes. Here we report a quinoline-derived ligand that enables the Pd(ii)-catalyzed olefination of the C(sp<sup>2</sup>)-H bond with simple aliphatic alkenes using a weakly coordinating monodentate amide auxiliary. Oxygen is used as the terminal oxidant with catalytic copper as the co-oxidant. A variety of functional groups in the aliph ...[more]

PMID: 29675177

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