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Ruthenium indenylidene complex

Indenylidene-Ruthenium Complexes the Alkene Metathesis Catalytic Species from Allenylidene Ruthenium Complexes... [Pg.256]

Scheme 8.11 Formation of indenylidene ruthenium complex accelerated bythe protonation of ruthenium allenylidene complex. Scheme 8.11 Formation of indenylidene ruthenium complex accelerated bythe protonation of ruthenium allenylidene complex.
Applications of Isolated Indenylidene-Ruthenium Complexes in ROMP... [Pg.261]

Two observations initiated a strong motivation for the preparation of indenylidene-ruthenium complexes via activation of propargyl alcohols and the synthesis of allenylidene-ruthenium intermediates. The first results from the synthesis of the first indenylidene complexes VIII and IX without observation of the expected allenylidene intermediate [42-44] (Schemes 8.7 and 8.8), and the initial evidence that the well-defined complex IX was an efficient catalyst for alkene metathesis reactions [43-44]. The second observation concerned the direct evidence that the well-defined stable allenylidene ruthenium(arene) complex Ib rearranged intramo-lecularly into the indenylidene-ruthenium complex XV via an acid-promoted process [22, 23] (Scheme 8.11) and that the in situ prepared [33] or isolated [34] derivatives XV behaved as efficient catalysts for ROMP and RCM reactions. [Pg.265]

Scheme 8.15 Preparation of indenylidene ruthenium complexes containing a NHC ligand. Scheme 8.15 Preparation of indenylidene ruthenium complexes containing a NHC ligand.
Actually, applications of indenylidene-ruthenium complexes for alkene metathesis were reported before, at a time when the action mode of their ruthenium allenylidene precursors was not known. These complexes catalyzed a variety of RCM reactions of dienes and enynes [31, 32, 47] (see Section 8.2.2). [Pg.268]

The indenylidene-ruthenium complexes were shown to be the actual alkene metathesis catalysts arising from the addition of propargylic alcohols [15-18]. The Dixneuf group [19, 20] later revealed that the intramolecular rearrangement of allenylidene-ruthenium complexes into indenylidene-ruthenium complexes was... [Pg.389]

From Allenylidene to Indenylidene Ruthenium Complexes and Catalysts... [Pg.391]

A few weeks later, Nolan [16] reported the indenylidene-ruthenium complexes 7-10, which contain a NHC ligand analogous to the Grubbs II catalyst. Using catalysts 6 and 7 -10, excellent activities were shown in the RCM reaction of various... [Pg.392]

Once the NHC was introduced onto the ruthenium center, the addition of pyridine (10 equiv.) led to the 16-electron, monopyridine indenylidene complexes 54a-f (Scheme 14.24) [55, 56, 65, 66]. Interestingly, from a synthetic point of view, this preparation can also be achieved starting from (triphenylphos-phine)(indenylidene)ruthenium complexes, thereby avoiding the use of the costly and sensitive tricyclohexylphosphine [50,66]. The monopyridine complexes bearing mesityl substituents on the nitrogens were not very active at room temperature for the RCM of dienes and enynes, nor in the CM of methyl acrylate [66]. However, the controlled ROMP of norbornene-type monomers was allowed [65]. In contrast, the indenylidene complexes 54b and 54f, which bear 2,6-diisopropylphenyl substituents on the NHC and either a pyridine or 3-bromopyridine ligand, were... [Pg.405]

Indenylidene-ruthenium complexes as catalytic precursors arising from allenylidene-ruthenium complexes... [Pg.21]


See other pages where Ruthenium indenylidene complex is mentioned: [Pg.274]    [Pg.274]    [Pg.486]    [Pg.389]    [Pg.391]    [Pg.392]    [Pg.399]    [Pg.409]    [Pg.412]    [Pg.614]   
See also in sourсe #XX -- [ Pg.486 ]

See also in sourсe #XX -- [ Pg.389 ]




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Applications of Isolated Indenylidene-Ruthenium Complexes in ROMP

Indenylidene

Indenylidene complexes

Indenylidene-ruthenium

Polymerization with Ruthenium Indenylidene Complexes

Ruthenium Indenylidene Complexes in Alkene Metathesis

Ruthenium indenylidene complex catalysts

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