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Protonolysis of a ruthenium-carbene bond and applications in olefin metathesis.

ABSTRACT: The synthesis of a ruthenium complex containing an N-heterocylic carbene (NHC) and a mesoionic carbene (MIC) is described wherein addition of a Brønsted acid results in protonolysis of the Ru-MIC bond to generate an extremely active metathesis catalyst. Mechanistic studies implicated a rate-determining protonation step in the generation of the metathesis-active species. The activity of the NHC/MIC catalyst was found to exceed those of current commercial ruthenium catalysts.

SUBMITTER: Keitz BK

PROVIDER: S-EPMC3121189 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Protonolysis of a ruthenium-carbene bond and applications in olefin metathesis.

Keitz Benjamin K BK Bouffard Jean J Bertrand Guy G Grubbs Robert H RH

Journal of the American Chemical Society 20110516 22

The synthesis of a ruthenium complex containing an N-heterocylic carbene (NHC) and a mesoionic carbene (MIC) is described wherein addition of a Brønsted acid results in protonolysis of the Ru-MIC bond to generate an extremely active metathesis catalyst. Mechanistic studies implicated a rate-determining protonation step in the generation of the metathesis-active species. The activity of the NHC/MIC catalyst was found to exceed those of current commercial ruthenium catalysts. ...[more]

PMID: 21574621

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