246047-72-3Relevant articles and documents
Ruthenium-indenylidene complexes: Powerful tools for metathesis transformations
Boeda, Fabien,Clavier, Herve,Nolan, Steven P.
, p. 2726 - 2740 (2008)
Ruthenium-indenylidene complexes represent a class of robust and efficient pre-catalysts for olefin metathesis reactions. In this feature article, we provide an overview of the various complexes belonging to this family and summarise their use in various applications. The relation between the nature of ancillary ligands around the metal coordination sphere of these complexes and their catalytic activity is also discussed. The Royal Society of Chemistry.
Merrifield resin-assisted routes to second-generation catalysts for olefin metathesis
Nascimento, Daniel L.,Davy, Emma C.,Fogg, Deryn E.
, p. 1535 - 1544 (2018)
Phosphine-scavenging resins can significantly facilitate the synthesis of highly active Ru metathesis catalysts, including the second-generation Grubbs, Hoveyda, and indenylidene catalysts (GII, HII, InII). These catalysts are customarily prepared by ligand exchange of the corresponding first-generation catalysts with the N-heterocyclic carbene (NHC) H2IMes. The PCy3 coproduct is conventionally removed by pentane extraction, but the partial solubility of the desired Ru products can cause product losses of over 20%. Sequestration of the PCy3 coproduct with CuCl is more efficient, but is undesirable given the potential for non-innocent copper residues. Use of the arylsulfonic acid resin Amberlyst-15 delivers near-quantitative catalyst yields, but the high acidity of the resin leads to problems with reproducibility and decomposition. An alternative approach is described, in which a neutral Merrifield resin (crosslinked polystyrene with pendant p-C6H4CH2I groups; MF-I) is used to sequester PCy3 as the covalently-tethered benzylphosphonium salt. Addition of MF-I following complete ligand exchange effects quantitative uptake of free PCy3 (and any residual free NHC) within 45 min at RT: the clean products are isolated by filtration, in ca. 95% yield. These yields compare well with those obtained via the Amberlyst-15 route, without the challenges due to resin acidity. The efficacy of this methodology is demonstrated in the synthesis of isotopically-labelled derivatives of HII, in which the H2IMes ligand bears a 13C-label at the carbene carbon, or perdeuterated mesityl rings.
N-Heterocyclic carbene-based ruthenium-hydride catalysts for the synthesis of unsymmetrically functionalized double-decker silsesquioxanes
Zak, Patrycja,Delaude, Lionel,Dudziec, Beata,Marciniec, Bogdan
, p. 4306 - 4309 (2018)
Ruthenium-N-heterocyclic carbene complexes with the generic formula [RuHCl(CO)(NHC)(PCy3)] exhibit a high catalytic activity toward the (E)-selective silylative coupling of divinyl-substituted double-decker silsesquioxanes with two distinctly substituted styrenes. This process leads to a novel class of unsymmetrically functionalized silsesquioxane derivatives.
Cross-metathesis reaction of functionalized and substituted olefins using group 8 transition metal carbene complexes as metathesis catalysts
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, (2016/08/29)
The invention pertains to the use of Group 8 transition metal carbene complexes as catalysts for olefin cross-metathesis reactions. In particular, ruthenium and osmium alkylidene complexes substituted with an N-heterocyclic carbene ligand are used to catalyze cross-metathesis reactions to provide a variety of substituted and functionalized olefins, including phosphonate-substituted olefins, directly halogenated olefins, 1,1,2-trisubstituted olefins, and quaternary allylic olefins. The invention further provides a method for creating functional diversity using the aforementioned complexes to catalyze cross-metathesis reactions of a first olefinic reactant, which may or may not be substituted with a functional group, with each of a plurality of different olefinic reactants, which may or may not be substituted with functional groups, to give a plurality of structurally distinct olefinic products. The methodology of the invention is also useful in facilitating the stereoselective synthesis of 1,2-disubstituted olefins in the cis configuration.