Ruthenium salts chloride

In terms of economical synthetic approaches to indoles, the synthesis of this heterocycle from anilines and trialkylammonium chlorides was effected in an aqueous medium (H20-dioxane) at 180°C in the presence of a catalytic amount of ruthenium(III) chloride hydrate and triphenylphosphine together with tin(II)chloride <00TL1811>. Muchowski devised a novel synthetic route to indole-4-carboxaldehydes and 4-acetylindoles 86 via hydrolytic cleavage of W-alkyl-5-aminoisoquinolinium salts 85 to homophthaldehyde derivatives upon heating in a two phase alkyl acetate-water system containing an excess of a 2 1 sodium bisulfite-sodium sulfite mixture <00JHC1293>. 

The metal-catalysed autoxidation of alkenes to produce ketones (Wacker reaction) is promoted by the presence of quaternary ammonium salts [14]. For example, using copper(II) chloride and palladium(II) chloride in benzene in the presence of cetyltrimethylammonium bromide, 1-decene is converted into 2-decanone (73%), 1,7-octadiene into 2,7-octadione (77%) and vinylcyclohexane into cyclo-hexylethanone (22%). Benzyltriethylammonium chloride and tetra-n-butylammo-nium hydrogen sulphate are ineffective catalysts. It has been suggested that the process is not micellar, although the catalysts have the characteristics of those which produce micelles. The Wacker reaction is also catalysed by rhodium and ruthenium salts in the presence of a quaternary ammonium salt. Generally, however, the yields are lower than those obtained using the palladium catalyst and, frequently, several oxidation products are obtained from each reaction [15]. 

The use of ruthenium salts to produce isocyanates from amines and CO has been patented by Stern and Spector (10). This likely corresponds to the more well-documented palladium (II) chloride reaction which occurs stoichiometric-ally under mild conditions according to Reaction 3 (10, II). 

Solutions of pentaammine(nitrogen)ruthenium(II) have been prepared from ruthenium (III) chloride and hydrazine hydrate.1,2 These solutions have been used to prepare pentaammine-haloruthenium(III) salts [Ru(NH3)6X]X2 (X = Cl, Br, I). [Ru(NH3)5C1]C12 has been converted to pure pentaammine-(nitrogen)ruthenium(II) salts—[Ru(NH3)5N2]X2 (X- = Cl-, Br-, I-, BF4-, PFg-)—via the reaction between azide ion and aquopentaammineruthenium(III).2 Hexaammineruthe-nium(III) salts—rRu(NH8)6]X3 (X = I-, BF4-)—have been prepared by the reaction between pentaamminechlororuthenium-(III) chloride and hydrazine monohydrochloride. 

Many ruthenium complexes have been tested in the silylative coupling reaction. In the synthetic procedure the absence of by-products of the homocoupling of vinylsilanes is required so an excess of the olefin has usually been used. However, the screening tests performed at the 1 1 ratio of styrene and phenyldimethylvinylsilane with a variety of ruthenium catalysts have shown that pentacoordinated monocarbonyl bisphosphine complexes appear to be the most active and selective catalysts of which RuHCl(CO)(PCy3)2 has shown high catalytic activity under conditions of catalyst loadings as low as 0.05 mol % [55]. Cuprous salts (chloride, bromide) have recently been reported to be very successful co-catalysts of ruthenium phosphine complexes, markedly increasing the rate and selectivities of all ruthenium phosphine complexes [54]. 

Of particular interest is Caesium Chlor-ruthenite, Cs,.RuC]6.H20, which Howe4 obtained by the action of hydrochloric acid on ruthenium tetroxide and subsequent addition of caesium chloride to the solution. The salt is precipitated as a dark brown powder, fairly soluble in water and hydrochloric acid, exhibiting the chemical reactions of a trivalent ruthenium salt. Howe also describes an isomeride of this salt, which lie termed, in accordance with Werner s nomenclature, Caesium Aquo-chlor-ruthenate [vide infra). 

With concentrated solutions of ruthenium salts, alkali chlorides effect the deposition of violet crystalline precipitates of the double chlorides. These are soluble in water only with difficulty, but are decomposed with boiling water, yielding black insoluble residues of oxychloride. 

Ignites in air above 288°C when exposed to spark. Potentially explosive reaction with aluminum chloride -I- bis(2-methoxyethyl) ether. Reacts with ruthenium salts to form a solid product which explodes when touched or on contact with water. Reacts to form dangerously explosive hydrogen gas on contact with alkali, water and other protic solvents (e.g., methanol, ethanol, ethylene glycol, phenol), aluminum chloride -I- bis(2-methoxyethyl)ether. Reacts violently with... 

In view of the purification and waste disposal problems with the chromium oxidations catalytic methods with ruthenium catalysts are more attractive. Ruthenium(Vlll) oxide is a strong oxidant that will also oxidize alkenes, alkynes, sulfides, and in some cases benzyl ethers. The method is compatible with glycosidic linkages, esters and acetals, and is usually carried out in a biphasic solvent system consisting of water and a chlorinated solvent. Acetonitrile or a phase-transfer catalyst has been shown to further promote the oxidation [29,30]. Normally, a periodate or a hypochlorite salt serve as the stoichiometric oxidant generating rutheni-um(VIII) oxide from either ruthenium(IV) oxide or ruthenium(III) chloride [30]. 

Ruthenium (III) chloride (2H2O) (P-form) [14898-67-0] M 207.4 + H2O, m >500°(dec), d 3.11, pKj 3.40 (for aquo Rh " " hydrolysis). Dissolve the salt in H2O, filter and concentrate to crystallisation in the absence of air to avoid oxidation. Evaporate the solution in a stream of HCl gas while being heated just below its boiling point until a syrup is formed and finally to dryness at 80-100° and dried in a vacuum over H2SO4. When heated at 700° in the presence of CI2 the insoluble a-form is obtained [Gmbe in Handbook of Preparative Inorganic Chemistry (Ed.Brauer) AcaAexmcPressWol II p 1598 1965, Carlsen et al. J Org Chem 46 3936 1981]. 

The use of electricity in reactions is clean and, at least in some cases, can produce no waste. Toxic heavy metal ions need not be involved in the reaction. Hazardous or expensive reagents, if needed, can be generated in situ where contact with them will not occur. The actual oxidant is used in catalytic amounts, with its reduced form being reoxidized continuously by the electricity. In this way, 1 mol% of ruthenium(III) chloride can be used in aqueous sodium chloride to oxidize benzyl alcohol to benzaldehyde at 25°C in 80% yield. The benzaldehyde can, in turn, be oxidized to benzoic acid by the same system in 90% yield.289 The actual oxidant is ruthenium tetroxide. Naphthalene can be oxidized to naphthoquinone with 98% selectivity using a small amount of cerium salt in aqueous methanesulfonic acid when the cerium(III) that forms is reoxidized to cerium(IV) electrically.290 Substituted aromatic compounds can be oxidized to the corresponding phenols electrically with a platinum electrode in trifluoroacetic acid, tri-ethylamine, and methylene chloride.291 With ethyl benzoate, the product is a mixture of 44 34 22 o/m/fhhy-... 

Ruthenium(III) chloride (RuCls) [3H2O 13815-94-6 XH2O 14898-67-0 Anhydrous 10049-08-8] M 207.4 (anhydrous), 261.5 (3H2O), 3.11. The anhydrous salt exists in two forms. The a-form is produced by the... 

Ruthenium is produced mainly from an anode slime yielded when crude copper or crude nickel, obtained from nickel sulfide ores, is electrolytically refined. The anode slime contains precious metal elements. It is treated with hot aqua regia and platinum, palladium and gold are separated as their chloro complexes. Then, by nitric acid treatment, fusion treatment with NaHS04, and fusion treatment with Na202, silver, rhodium and iridium are separated. The residual ruthenium and osmium salts are dissolved in water, and the osmium is separated by treatment with chlorine, hydrochloric acid and nitric acid. The ruthenium salt is treated with ammonium chloride to afford a ruthenium salt ((NH4)3RuCl6), and the reduction with hydrogen yields ruthenium powder [1,4-6]. 

When ruthenium(III) chloride is heated in an atmosphere of carbon monoxide at 65 atmospheres, [Ru3(CO)i2l forms." Reduction of hydrated iridium trichloride by CO has been reported by Balch and coworkers. 8 mixture of the iridium salt and LiCl in 2-methoxyethanol was reacted with CO under pressure at 170 °C forming Li[IrCl2(CO)2]- When a toluene solution of l,3-bis(diphenylphosphino)propane was added to the reaction medium. 

Carboxylic acids and their salts, as well as alcohols and alkoxides, are common ligands and this has limited their use as reductants in synthesis. Potassium hexachloroplatinate(IV), for example, is reduced by ammonium oxalate.63 Che and coworkers 4 have shown that the reaction of aqueous solutions of ascorbic acid with the complex, [Ru02(NH3)4]Cl2, in the presence of NaX (X = Cl, I, CNS) yields the complexes, [RuX2(NH3)4]X. The reduction of a mixture of hydrated ruthenium(III) chloride and ruthenium(IV) chloride by glucose or ascorbic acid in water in the presence of 2,2 -bipyridyl results in the formation of [Ru(bipy)3]Cl2 7H20. 5 Additionally, the reduction of the [Tc04] anion by gluconic acid has been studied. ... 

Addition Across Alkenes and Alkynes. In the presence of a catalyst (usually Copper or ruthenium), methanesulfonyl chloride adds across alkenes and alkynes to produce (3-chloro sulfones. The stereochemistry of the product of addition across phenylacety-lene depends on the reaction conditions used. In the absence of an added hydrochloride salt, the cis addition product predominates (eq 24), whereas the trans product is favored when the salt is added (eq 25). 

The residue, which contains Ir, Ru, and Os, is fused with sodium peroxide at 500°C, forming soluble sodium mthenate and sodium osmate. Reaction of these salts with chlorine produces volatile tetroxides, which are separated from the reaction medium by distillation and absorbed into hydrochloric acid. The osmium can then be separated from the mthenium by boiling the chloride solution with nitric acid. Osmium forms volatile osmium tetroxide mthenium remains in solution. Ruthenium and osmium can thus be separately purified and reduced to give the metals. 

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