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Complex Cp*Ru

A theoretical basis for the description of the cationic complex [Cp Ru(PR3)2 = = SiR2]+ can also be given. For a d6 CpML2 system, a complete splitting of the three orbitals (octahedral symmetry) is to be expected. Consequently, a coordinated silylene ligand (without any base) should prefer the indicated (Fig. 10) conformation. [Pg.25]

Tilley and co-workers reported the isolation of coordinatively unsaturated complexes Cp Ru(L)Cl (Cp =/j -C-sMes, L = PCy3 and P Pr ) by a simple reaction with the tetrameric species fCp RuCI]4. This synthetic pathway has allowed us... [Pg.183]

Scheme 14.5 Stereoselective hydrogenation of internal alkynes by complex [Cp Ru(z/4-CH3CH=CHCH=CHC00H)][CF3S03] (11) the anion is CF3S03 throughout [1 7],... Scheme 14.5 Stereoselective hydrogenation of internal alkynes by complex [Cp Ru(z/4-CH3CH=CHCH=CHC00H)][CF3S03] (11) the anion is CF3S03 throughout [1 7],...
The bare nitrogen analog of dihydroazaborine, where the R substituent on N is effectively replaced by an electron pair, is the azaboratabenzene anion H4C4BRN. The synthesis of this ligand and a ruthenium sandwich complex Cp Ru(H4C4BPhN) that is catalytically active in the acylation of benzyl alcohol have been reported.151... [Pg.43]

Girolami and coworkers have shown that the methylene/silyl complex Cp Ru(/z-CH2)(/z-Cl)Cp Ru(SiMe3) undergoes low-and high-energy dynamic processes in which... [Pg.2075]

Reactions of the silene hydride complex Cp Ru(P(Pr-/)3)(I I)(r 2-C.I I2=SiPh2) with hydrosilanes proceed via an initial migration of the hydride to the silene ligand, affording as the final products either the disilyl hydride or the mono silyl dihydrido ruthenium(IV) complexes as described in Scheme 21. Similar reductive elimination and... [Pg.2080]

The ruthenium complex Cp Ru(bipyridyl)Cl has been developed as a catalyst for the first regioselective tandem Michael addition-allylic alkylation of activated Michael acceptors. The net outcome is the decarboxylative insertion of Michael acceptors into allyl /3-keto esters to produce (215). The reaction combines the generation of Ru-tt-allyl and enolate from (213) the enolate is first added to the Michael acceptor (214) and the resulting species is captured by the Ru-tt-allyl.254... [Pg.339]

A similar rapid exchange of bridging and terminal hydride ligands and the hydrogen atoms in Ru-H-Si 3c-2e bonds is observed in the C-type diruthenium complexes Cp Ru(ju.- T2-HSiR2) 2(Ju,-H)(H) (R = Et, Ph) [see Eq. (13)].38 In these complexes, all the four hydride ligands are equivalent in the H NMR spectrum at 25°C, whereas they separate to three signals... [Pg.279]

Cyclic seven-membered vinyl silanes 161 were obtained by regio- and stereoselective hydrosilylation of internal alkynes catalyzed by the ruthenium complex [Cp Ru(MeCN)3]PF6, as shown in Equation (33) <2005JA10028>. Hydrosilylation of 2,2-divinyladamantane with bis(hydrosilane) species 162 in the presence of Zeise s dimer [Pt2Cl4(CH2CH2)2] gave the disilacyclic 163 in high yields (Equation 34) <19980M4267>. [Pg.1001]

Silicon. The first base-stabihzed silylene complex [Cp Ru =Si(Ph)2NCMe (PMe3)2] was reported in 1987, and the first base-free silylene-containing complexes [Cp Ru=Si(SR)2(PMe3)2] (R = Me or Ph) were not synthesized until 1990, much later than for the heavier congeners Ge, Sn, and Pb. Recently, the silylene-containing... [Pg.2801]

The 1,5 cyclooctadiene complex [Cp Ru(jj rf--C Yiu) (CO)]OTf was isolated upon treatment of Cp Ru(j)" -butadiene)X (X = Cl, Br) with butadiene, AgOTf, and CO. A similar [4-1-4] cycloaddition (a thermally forbidden reaction see Woodward-Hoffmann Rules)) is observed when Cp Ru(isoprene)Cl is treated with iso-prene, AgOTf, and CO. Likewise, the reaction of 1,3-pentadiene with Cp Ru( ) -l,3-pentadiene)Cl results in linear dimerization to form [Cp Ru(4-methyl-(l,3-jj 6-8-j) )-nonadienediyl)]OTf. These types of dimerization occur with both stoichiometric and catalytic amounts of the ruthenium complex. ... [Pg.4164]

The trinuclear pentahydride complex [Cp Ru]3(/w-H)3(/x3-H)2 (105) in Scheme 26 consists of ruthenium centers tightly bound by bridging hydrides. Treatment of the pentahydride complex with excess butadiene in THF results in a trinuclear 1-methyl-1,3-dimetalloallyl complex [Cp"Ru]3(H)4[/x3- ] -C(Me)CHCH] (106). This interaction shows the cooperation of all three ruthenium centers as either coordination sites or activation sites. Similar results are found by treating (105) with isoprene. Treatment of (105) with five equivalents of cyclopentadiene results in bond cleavage of the cyclopentadiene to form a dark purple crystalline solid [Cp Ru(/u.-H)]3[/x3- j4-C(Me)=CHCH=CH] (107). In this complex, two of the ruthenium centers act as a coordination site, while the third is an activation... [Pg.4165]

Effects of temperature and isotopic substitution on a /hh coupling in the cationic ruthenium complex [Cp Ru(dppm)(H2)] have been studied by Law... [Pg.147]

With the unsubstituted Py, the stable tris(N-bonded) adduct [CpRu(r (N)-Py)3] has been obtained. However, when the permethylated ligand Cp is employed in order to increase the electron density around the Ru center more, the complex [Cp Ru(Ti (N)-Pylsl is a kinetic product that thermally converts to the corresponding ti derivative (Eq. 6.12). [Pg.163]

PHIP allows also the PASADENA investigation ofthe stereoselectivity ofa reaction. A typical example is given in Ref [70], where the stereoselective hydrogenation of 3-hex-yne-l-ol under the influence of the cationic ruthenium complex [Cp Ru(// -... [Pg.662]

Fagan studied the reaction of C o with the complex [Cp Ru(CH3CN)3] and found that it did not lose all three molecules of acetonitrile to form a q -complex as observed for aromatic systems, but rather gave a Tj -olefin complex by releasing just one ligand of acetonitrile. With some sufficiently nucleophihc hydrido... [Pg.81]

The first ruthenium dihaloboryl Cp/Ru(CO)2BCl2 (8.102) has recently been spectroscopically characterized, although no structural data were reported [60]. As with the related iron complex CpFe(CO)2BCl2 (8.35), 8.102 exhibits the relatively downfield-shifted 11B resonance (5b 81.0) and high frequency carbonyl stretching bands (2012, 1958 cm-1), expected for a boryl system featuring poorly 7r-donating substituents. The ferrocenyl(bromo)boryl complex Cp/Ru(CO)2B(Fc)Br (8.101) has also been synthesized recently and has spectroscopic properties similar to those of the closely related iron systems 8.63 and 8.64 [92]. [Pg.73]

A one-step chemical procedure (i, in the scheme) has proved valuable. Thus cholesterol and its oxidation product, dehydroisoandrosterone have been selectively aromatised by reaction with the electrophilic ruthenium complex (Cp Ru ), t -cyclopentadienyl Ru. obtained by protonation in THF of [Cp Ru(OMe)j2 (1 mol) with triflic acid, CF3SO3H (2 mol). The addition of cholesterol (2 mol) in THF during 40 hours at 120°C (or in dichloromethane at 90 C) afforded estrone in 48% yield with evolution of methane (ref. 114). [Pg.592]


See other pages where Complex Cp*Ru is mentioned: [Pg.609]    [Pg.621]    [Pg.380]    [Pg.13]    [Pg.530]    [Pg.249]    [Pg.241]    [Pg.674]    [Pg.2080]    [Pg.2082]    [Pg.2082]    [Pg.99]    [Pg.142]    [Pg.375]    [Pg.376]    [Pg.379]    [Pg.1595]    [Pg.4164]    [Pg.465]    [Pg.116]    [Pg.163]    [Pg.209]    [Pg.209]    [Pg.210]    [Pg.211]    [Pg.74]    [Pg.113]    [Pg.465]    [Pg.374]    [Pg.378]    [Pg.1594]    [Pg.4163]   


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Ru -complexes

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