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Ni-Catalyzed Regioselective 1,2-Dialkylation of Alkenes Enabled by the Formation of Two C(sp³)-C(sp³) Bonds.

ABSTRACT: We disclose a Ni-catalyzed vicinal difunctionalization of alkenes with benzyl halides and alkylzinc reagents, which produces products with two new alkyl-alkyl bonds. This alkene dialkylation is effective in combining secondary benzyl halides and secondary alkylzinc reagents with internal alkenes, which furnishes products with three contiguous all-carbon secondary stereocenters. The products can be readily elaborated to access complex tetralene, benzosuberene, and bicyclodecene cores. The reaction also features as the most efficient alkene difunctionalization process to date with catalyst loadings down to 500 ppm and the catalytic turnover number (TON) and turnover frequency (TOF) registering up to 2 × 10³ and 165 h^-1 at rt, respectively.

SUBMITTER: Dhungana RK

PROVIDER: S-EPMC7953840 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Ni-Catalyzed Regioselective 1,2-Dialkylation of Alkenes Enabled by the Formation of Two C(sp3)-C(sp3) Bonds.

Dhungana Roshan K RK Sapkota Rishi R RR Wickham Laura M LM Niroula Doleshwar D Giri Ramesh R

Journal of the American Chemical Society 20201203 50

We disclose a Ni-catalyzed vicinal difunctionalization of alkenes with benzyl halides and alkylzinc reagents, which produces products with two new alkyl-alkyl bonds. This alkene dialkylation is effective in combining secondary benzyl halides and secondary alkylzinc reagents with internal alkenes, which furnishes products with three contiguous all-carbon secondary stereocenters. The products can be readily elaborated to access complex tetralene, benzosuberene, and bicyclodecene cores. The reactio ...[more]

PMID: 33271014

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