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Enantioconvergent Cross-Couplings of Alkyl Electrophiles: The Catalytic Asymmetric Synthesis of Organosilanes.

ABSTRACT: Metal-catalyzed enantioconvergent cross-coupling reactions of alkyl electrophiles are emerging as a powerful tool in asymmetric synthesis. To date, high enantioselectivity has been limited to couplings of electrophiles that bear a directing group or a proximal p/? orbital. Herein, we demonstrate for the first time that enantioconvergent cross-couplings can be achieved with electrophiles that lack such features; specifically, we establish that a chiral nickel catalyst can accomplish Negishi reactions of racemic ?-halosilanes with alkylzinc reagents with good enantioselectivity under simple and mild conditions, thereby providing access to enantioenriched organosilanes, an important class of target molecules.

SUBMITTER: Schwarzwalder GM

PROVIDER: S-EPMC6399024 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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