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Catalyzing the Hydrodefluorination of CF3-Substituted Alkenes by PhSiH3. H• Transfer from a Nickel Hydride.

ABSTRACT: The hydrodefluorination of CF3-substituted alkenes can be catalyzed by a nickel(II) hydride bearing a pincer ligand. The catalyst loading can be as low as 1 mol%. gem-Difluoroalkenes containing a number of functional groups can be formed in good to excellent yields by a radical mechanism initiated by H• transfer from the nickel hydride. The relative reactivity of various substrates supports the proposed mechanism, as does a TEMPO trapping experiment.

SUBMITTER: Yao C

PROVIDER: S-EPMC7102444 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Catalyzing the Hydrodefluorination of CF3-Substituted Alkenes by PhSiH3. H• Transfer from a Nickel Hydride.

Yao Chengbo C Wang Shuai S Norton Jack J Hammond Matthew M

Journal of the American Chemical Society 20200124 10

The hydrodefluorination of CF3-substituted alkenes can be catalyzed by a nickel(II) hydride bearing a pincer ligand. The catalyst loading can be as low as 1 mol%. gem-Difluoroalkenes containing a number of functional groups can be formed in good to excellent yields by a radical mechanism initiated by H• transfer from the nickel hydride. The relative reactivity of various substrates supports the proposed mechanism, as does a TEMPO trapping experiment. ...[more]

PMID: 31935083

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