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Ruthenium metallacycles derived from 14-electron complexes. New insights into olefin metathesis intermediates.

ABSTRACT: Ruthenium(IV) metallacycles derived from both ethylene and propene are reported. The propene-derived metallacycles represent the first observed examples of substituted ruthenacyclobutanes and offer new insight into the preferred stereochemical orientation about metathesis intermediates. In addition, a metallacycle possessing an unsymmetrical N-heterocyclic carbene (NHC) ligand was prepared and investigated to ascertain the dynamics of the NHC relative to the metallacycle ring. Metallacycles investigated were found to possess exchange cross-peaks between the alpha- and beta-positions in the 2D NMR, indicating a dynamic structure. The implications of these results to the mechanism of ruthenium-catalyzed olefin metathesis are discussed.

SUBMITTER: Wenzel AG

PROVIDER: S-EPMC2533258 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Ruthenium metallacycles derived from 14-electron complexes. New insights into olefin metathesis intermediates.

Wenzel Anna G AG Grubbs Robert H RH

Journal of the American Chemical Society 20061201 50

Ruthenium(IV) metallacycles derived from both ethylene and propene are reported. The propene-derived metallacycles represent the first observed examples of substituted ruthenacyclobutanes and offer new insight into the preferred stereochemical orientation about metathesis intermediates. In addition, a metallacycle possessing an unsymmetrical N-heterocyclic carbene (NHC) ligand was prepared and investigated to ascertain the dynamics of the NHC relative to the metallacycle ring. Metallacycles inve ...[more]

PMID: 17165753

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