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Improved ruthenium catalysts for Z-selective olefin metathesis.

ABSTRACT: Several new C-H-activated ruthenium catalysts for Z-selective olefin metathesis have been synthesized. Both the carboxylate ligand and the aryl group of the N-heterocyclic carbene have been altered and the resulting catalysts evaluated using a range of metathesis reactions. Substitution of bidentate with monodentate X-type ligands led to a severe attenuation of metathesis activity and selectivity, while minor differences were observed between bidentate ligands within the same family (e.g., carboxylates). The use of nitrato-type ligands in place of carboxylates afforded a significant improvement in metathesis activity and selectivity. With these catalysts, turnover numbers approaching 1000 were possible for a variety of cross-metathesis reactions, including the synthesis of industrially relevant products.

SUBMITTER: Keitz BK

PROVIDER: S-EPMC3257350 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Improved ruthenium catalysts for Z-selective olefin metathesis.

Keitz Benjamin K BK Endo Koji K Patel Paresma R PR Herbert Myles B MB Grubbs Robert H RH

Journal of the American Chemical Society 20111209 1

Several new C-H-activated ruthenium catalysts for Z-selective olefin metathesis have been synthesized. Both the carboxylate ligand and the aryl group of the N-heterocyclic carbene have been altered and the resulting catalysts evaluated using a range of metathesis reactions. Substitution of bidentate with monodentate X-type ligands led to a severe attenuation of metathesis activity and selectivity, while minor differences were observed between bidentate ligands within the same family (e.g., carbo ...[more]

PMID: 22097946

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