Nickel-Catalyzed Asymmetric Propargylic Alkylation via Photocatalytic Nucleophile Generation

Abstract We report a three-component asymmetric propargylic substitution enabled by the merger of decatungstate photocatalysis and nickel catalysis. This protocol facilitates direct C(sp³)–H functionalization of cyclic alkanes, alkenes, and ethers via Giese-type addition to 2-arylacrylates, generating nonstabilized carbanions in situ through a radical/ionic relay process. These nucleophilic intermediates undergo highly enantioselective coupling with allenylnickel species (formed from propargylic carbonates and a chiral nickel catalyst) to afford chiral propargylic products with up to 95% ee.