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Sodium Diisopropylamide in Tetrahydrofuran: Selectivities, Rates, and Mechanisms of Arene Metalations.

ABSTRACT: Sodium diisopropylamide (NaDA)-mediated metalations of arenes in tetrahydrofuran (THF)/hexane or THF/Me2NEt solutions are described. A survey of >40 benzenoid- and pyridine-based arenes with a range of substituents demonstrates the efficacy and regioselectivity of metalation. Metalations of activated disubstituted arenes and selected monosubstituted arenes are rapid at -78 °C. Rate studies of 1,3-dimethoxybenzene and related methoxylated arenes show exclusively monomer-based orthometalations with two or three coordinated THF ligands. Rate studies of the isotopic exchange of benzene and monosubstituted arenes with weakly activating groups reveal analogous di- and trisolvated monomer-based metalations. Cooperative inductive, mesomeric, steric, and chelate effects are discussed.

SUBMITTER: Algera RF

PROVIDER: S-EPMC6059610 | biostudies-other | 2017 Oct

REPOSITORIES: biostudies-other

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Sodium Diisopropylamide in Tetrahydrofuran: Selectivities, Rates, and Mechanisms of Arene Metalations.

Algera Russell F RF Ma Yun Y Collum David B DB

Journal of the American Chemical Society 20171016 42

Sodium diisopropylamide (NaDA)-mediated metalations of arenes in tetrahydrofuran (THF)/hexane or THF/Me<sub>2</sub>NEt solutions are described. A survey of >40 benzenoid- and pyridine-based arenes with a range of substituents demonstrates the efficacy and regioselectivity of metalation. Metalations of activated disubstituted arenes and selected monosubstituted arenes are rapid at -78 °C. Rate studies of 1,3-dimethoxybenzene and related methoxylated arenes show exclusively monomer-based orthometa ...[more]

PMID: 28946744

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