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Ni(I)-Catalyzed β,δ-Vinylarylation of γ,δ-Alkenyl α-Cyanocarboxylic Esters via Contraction of Transient Nickellacycles

ABSTRACT: We disclose a transmetalation-initiated Ni(I)-catalyzed regioselective β,δ-vinylarylation of γ,δ-alkenyl α-cyanocarboxylic esters with vinyl triflates and arylzinc reagents. This reaction proceeds via contraction of six-membered nickellacycles to five-membered nickellacycles to form carbon–carbon bonds at the nonclassical homovicinal sites, and it provides expeditious access to a wide range of complex aliphatic α-cyanoesters, α-cyanocarboxylic acids, dicarboxylic acids, dicarboxylic acid monoamides, monocarboxylic acids, nitriles, and spirolactones. Control, deuterium labeling, and crossover experiments indicate that (i) the nickellacycle contraction occurs by β-H elimination, followed by hydronickellation on transiently formed alkenes, and (ii) the Ni species are stabilized as Ni-enolates. Graphical Abstract

SUBMITTER: Dhungana R

PROVIDER: S-EPMC8171255 | biostudies-literature |

REPOSITORIES: biostudies-literature

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