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Catalytic reductive [4 + 1]-cycloadditions of vinylidenes and dienes.

ABSTRACT: Cycloaddition reactions provide direct and convergent routes to cycloalkanes, making them valuable targets for the development of synthetic methods. Whereas six-membered rings are readily accessible from Diels-Alder reactions, cycloadditions that generate five-membered rings are comparatively limited in scope. Here, we report that dinickel complexes catalyze [4 + 1]-cycloaddition reactions of 1,3-dienes. The C1 partner is a vinylidene equivalent generated from the reductive activation of a 1,1-dichloroalkene in the presence of stoichiometric zinc. Intermolecular and intramolecular variants of the reaction are described, and high levels of asymmetric induction are achieved in the intramolecular cycloadditions using a C 2-symmetric chiral ligand that stabilizes a metal-metal bond.

SUBMITTER: Zhou YY

PROVIDER: S-EPMC6467289 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Catalytic reductive [4 + 1]-cycloadditions of vinylidenes and dienes.

Zhou You-Yun YY Uyeda Christopher C

Science (New York, N.Y.) 20190201 6429

Cycloaddition reactions provide direct and convergent routes to cycloalkanes, making them valuable targets for the development of synthetic methods. Whereas six-membered rings are readily accessible from Diels-Alder reactions, cycloadditions that generate five-membered rings are comparatively limited in scope. Here, we report that dinickel complexes catalyze [4 + 1]-cycloaddition reactions of 1,3-dienes. The C<sub>1</sub> partner is a vinylidene equivalent generated from the reductive activation ...[more]

PMID: 30792299

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