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Sulfoxide, dimethyl-, ruthenium complex

In our application to molecular hysteresis accompanying a change in oxidation state, we have exploited linkage isomerization of ruthenium and osmium complexes (oxidation states 2+ and 3+). An early example in this circumscribed field is the linkage isomerization observed for the pentammine ruthenium complex with dimethyl sulfoxide when the oxidation state changes from 2+ (heteroligand attached at S) to 3+ (relocation to oxygen) (Fig. 3A) [13, 14]. The points of attachment have been confirmed by X-ray diffraction... [Pg.119]

Ruthenium(II) complexes dimethyl sulfoxide, 490 hydrogen sulfide, 516... [Pg.1096]

The electroactivity of a redox polymer may depend upon the solvent with which the surface modified electrode is in contact. Thus, for example, PVP containing an EDTA complex of ruthenium(III) is electroactive in contact with aqueous media, but inactive in contact with solvents such as dimethyl sulfoxide. [Pg.18]

There are several methods reported in the literature for transforming vicinal diols into ct-diketones while avoiding the risk of C-C bond cleavage.26 Examples include the standard Swem conditions (dimethyl sulfoxide and oxalyl chloride followed by triethylamine), or the use of DMSO activated by acetic anhydride, pyridine-sulfur trioxide complex, or dicyclohexylcarbodiimide (Mq/J-att oxidation). Diones are also obtained by treatment with benzalacetone as a hydride acceptor in the presence of catalytic amounts of tris(triphenylphosphine)ruthenium dichlonde [(PPh RuCFl.27 Recent developments include the use of w-iodoxyben/.oic acid28 or the oxoammonium salt of 4-acctamidoletramethylpipcridine-1-oxyl and y -toluencNulfonic acid.29... [Pg.156]

Freshly prepared a s-[Ru(en)2(N8)2]PFt is paramagnetic (/i. = 2.0 B.M.). In the air at room temperature the purple-red crystals decompose over a few days to a dark brown mixture of cis-[Ru(en)2(N2)(N8)]PF6 and unknown nitrosyl ruthenium species. It may be stored in the dark at — 15°C. for several weeks without significant change. Its i.r. spectrum shows a characteristic coordinated azide-ion band at 2050 cm.-1. Most samples also show a sharp weak peak at 2130 cm.-1, which is due to the presence of small amounts of cis-[Ru(en)2(N2)(N8)]PF. CTs-[Ru(en)2(N8)2]PF8 is readily soluble in water and dimethyl sulfoxide, in which it is initially a typical 1 1 electrolyte. Subsequent complex chemical changes occur in these solvents. In acetone, methanol, and acetonitrile, however, as-[Ru (en) 2 (N8) 2]+ converts cleanly and quantitatively to cis-[Ru(en)2(N2)(N8)]+. [Pg.25]

Mestroni G, Alessio E, Calligaris M, Attia WM, Quadrifoglio F, Cauci S, Sava G, Zorzet S, Pacor S (1989) Chemical, biological and antitumor properties of mthenium(II) complexes with dimethyl sulfoxide. In Alessio E, Clarke MJ (eds) Ruthenium and other non-platinum metal complexes in cancer chemotherapy. Springer-Verlag, Berlin, New York, pp 71-87... [Pg.49]

Smith MK, Gibson JA, Young CG, Broomhead JA, Junk PC, Keene FR. Photoinduced ligand isomerization in dimethyl sulfoxide complexes of ruthenium(II). Eur J Inorg Chem 2000 1365-70. [Pg.71]

Even with immobilized catalysts being developed, removal of ruthenium by-products remains an important challenge. Georg and coworkers found that addition of 50 equiv (relative to ruthenium) of dimethyl sulfoxide or triphenylphosphine oxide brought ruthenium levels in reaction mixtures down from 50 to l-2qgmg-. The ruthenium levels in purified products are similar to those reported by Grubbs, where the metal was removed as trishydroxymethylphosphine complexes, " and those from the Pb(OAc)4 oxidation of ruthenium reported by Paquette. [Pg.5636]

Diarylacetylenes are converted in 55-90% yields into a-diketones by refluxing for 2-7 h with thallium trinitrate in glyme solutions containing perchloric acid [413. Other oxidants capable of achieving the same oxidation are ozone [84], selenium dioxide [509], zinc dichromate [660], molybdenum peroxo complex with HMPA [534], potassium permanganate in buffered solutions [848, 856, 864,1117], zinc permanganate [898], osmium tetroxide with potassium chlorate [717], ruthenium tetroxide and sodium hypochlorite or periodate [938], dimethyl sulfoxide and iV-bromosuccin-imide [997], and iodosobenzene in the presence of a ruthenium catalyst [787] (equation 143). [Pg.91]

Dimethyl sulfoxide solutions of [(CgHe)RuCl2]2 were shown to react with nucleophiles such as H , OH , or CN . Nuclear magnetic resonance studies showed the presence of cyclohexadienyl complexes, but the compounds were too unstable to be isolated, and the identity of the other ligands coordinated to the ruthenium atom is uncertain (462, 464). [Pg.104]

A Cr(VI) sulfoxide complex has been postulated after interaction of [CrOjtClj] with MejSO (385), but the complex was uncharacterized as it was excessively unstable. It was observed that hydrolysis of the product led to the formation of dimethyl sulfone. The action of hydrogen peroxide on mesityl ferrocencyl sulfide in basic media yields both mesityl ferrocenyl sulfoxide (21%) and the corresponding sulfone (62%) via a reaction similar to the Smiles rearrangement (165). Catalytic air oxidation of sulfoxides by rhodium and iridium complexes has been observed. Rhodium(III) and iridium(III) chlorides are catalyst percursors for this reaction, but ruthenium(III), osmium(III), and palladium(II) chlorides are not (273). The metal complex and sulfoxide are dissolved in hot propan-2-ol/water (9 1) and the solution purged with air to achieve oxidation. The metal is recovered as a noncrystalline, but still catalytically active, material after reaction (272). The most active precursor was [IrHClj(S-Me2SO)3], and it was observed that alkyl sulfoxides oxidize more readily than aryl sulfoxides, while thioethers are not oxidized as complex formation occurs. [Pg.150]

The nature of the solvent was found to play an important role for the catalytic activity and selectivity in the aerobic allylic oxidation of a-isophorone to KIP with phosphomolybdic acid (PMA). With 0.43 mol% PMA and potassium tert-butoxide as the additive in dimethyl sulfoxide (DMSO) at 115°C, KIP was obtained in 70% selectivity at 99% conversion.Using a ruthenium-porphyrin complex as the catalyst, the oxidation of a-isophorone with 2,6-dichloropyridine N-oxide in dichloromethane at 40°C afforded KIP at 99% selectivity and 75% con-... [Pg.400]

In parallel, it was reported by Housecroft and coworkers a completely different metalloden-dritic system based on a pentaerythritol, as a core molecule, and four carboranyl-functionalized complexes of 2,2 6, 2"-terpyridine ruthenium. The reaction of pentaerythrytol with 4 -Cl-2,2 6, 2" -terpyridine in dimethyl sulfoxide (DMSO) in the presence of KOH gave a molecule that contains four tpy metal-binding sites, the crucial point for the formation of the metallodendrimer. The reaction of this with the carboranyl-functionalized Ru complex [Ru 4 -[2-(tert-butyldimethylsilyl)-l,2-carboranyl]-2,2 6, 2"-ter-pyridine Cl3], [Ru(sicarbtpy)Cl3], in ethane-l,2-diol at 120°C led to the formation of the first generation of a cationic tetranuclear metallodendrimer (Scheme 27.12), confirmed by NMR and MALDI-TOF. [Pg.722]

Octahedral Ruthenium(II) and (III) complexes [Ru(NH3)5(dmso)] " " " " exhibit linkage isomerism [2] as both sulphur and oxygen are potential coordinating atoms in dimethyl sulfoxide, as shown in Figure 11. [Pg.75]

The diimine ligands 2-(phenylazo)pyridine and its p-methyl derivative [(33) R = H or Me] form bis complexes [Ru(LL)2XY]" with ruthenium(II). The complexes with X = Y = Cl, Br, or I (n = 0) react with tertiary phosphines by a second-order process with /c2 values apparently controlled by the bulk of the entering ligand. The complexes with X = py, Y = OH2, and X = Y = OH2 n = 2) react quite quickly with donor solvents such as acetronitrile or dimethyl sulfoxide the bis-aquo complex also reacts rapidly with pyridine. Complexes d5-[Ru(LL)2X2], when LL = an aryl-azooxime [(34) with R = aryl], readily lose HX on addition of a base such... [Pg.231]


See other pages where Sulfoxide, dimethyl-, ruthenium complex is mentioned: [Pg.73]    [Pg.107]    [Pg.647]    [Pg.79]    [Pg.384]    [Pg.124]    [Pg.14]    [Pg.159]    [Pg.320]    [Pg.822]    [Pg.165]    [Pg.23]    [Pg.32]    [Pg.207]    [Pg.320]    [Pg.86]    [Pg.220]    [Pg.1282]    [Pg.145]    [Pg.235]    [Pg.340]    [Pg.172]   
See also in sourсe #XX -- [ Pg.35 , Pg.35 , Pg.150 , Pg.151 ]




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Ruthenium sulfoxide complexes

Sulfoxide complexes

Sulfoxides dimethyl

Sulfoxides dimethyl sulfoxide

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