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Mechanism of the Ni(0)-catalyzed vinylcyclopropane-cyclopentene rearrangement.

ABSTRACT: A combination of physical organic experiments and quantum chemical calculations were used to construct a detailed mechanistic model for the Ni(0)-N-heterocyclic carbene-catalyzed vinylcyclopropane-cyclopentene rearrangement that involves a mutistep oxidative addition/haptotropic shift/reductive elimination pathway. No evidence for the intermediacy of radicals or zwitterions was found. The roles of substituents on the vinylcyclopropane substrate and variations in the ligands on Ni were evaluated. It is postulated that bulky carbene ligands facilitate formation of the active catalyst species.

SUBMITTER: Wang SC

PROVIDER: S-EPMC2762793 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Mechanism of the Ni(0)-catalyzed vinylcyclopropane-cyclopentene rearrangement.

Wang Selina C SC Troast Dawn M DM Conda-Sheridan Martin M Zuo Gang G LaGarde Donna D Louie Janis J Tantillo Dean J DJ

The Journal of organic chemistry 20091001 20

A combination of physical organic experiments and quantum chemical calculations were used to construct a detailed mechanistic model for the Ni(0)-N-heterocyclic carbene-catalyzed vinylcyclopropane-cyclopentene rearrangement that involves a mutistep oxidative addition/haptotropic shift/reductive elimination pathway. No evidence for the intermediacy of radicals or zwitterions was found. The roles of substituents on the vinylcyclopropane substrate and variations in the ligands on Ni were evaluated. ...[more]

PMID: 19780523

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