Ruthenium trichloride hydrates

Mild allylic oxidation of the A-2-crotyl-substituted thiadiazolidinone 1,1-dioxide 140 by sodium metaperiodate/ ruthenium trichloride hydrate (RuC13) gave the aldehyde 141. Excess oxidizing agent afforded the carboxylic acid 142 (Equation 26) <1999EJ02275>. 

A solution of 18 g (68 mmol) of commercial ruthenium trichloride hydrate (Johnson Matthey, 40 3% ruthenium) in a mixture of isoprene (680 mL) and 2-methoxyethanol (280 mL) is heated at reflux for 10 days under inert gas (nitrogen or argon). The purple crystalline product is collected in a medium-porosity sintered-glass funnel, washed with diethyl ether, and dried in vacuo yield 19.9 g (95%). 

Dodecacarbonyltriruthenium can be prepared by several methods. Johnson and Lewis1 have reported a procedure in which ruthenium trichloride hydrate is converted to tris(2,4-pentanedionato)ruthenium(III), which is turn is reacted with hydrogen and carbon monoxide. Reaction pressure and temperature are high (160 atm and 165 °C) and the yield is in the range from 50 to 55%. 

Mantovani and Cenini3 have also reported a two-step ambient pressure synthesis of dodecacarbonyltriruthenium starting with ruthenium trichloride hydrate resulting in a 50 to 60% yield but the product requires recrystallization. 

Hydrates of RUCI3, IrCl3, and OSCI3 are suitable catalysts for the ROMP of norbomene in aqueous and alcoholic solvents. Ruthenium trichloride hydrate is used for the industrial production of poly(norbornene). These hydrates act for the ROMP of norbomene and norbomene derivatives in pure water through an emulsion process (18). 

Acknowledgments The author would like to thank past and present members of his group, financial support from the Swiss National Science Foundation, and the Johnson Matthey Technology Centre for a generous loan of ruthenium trichloride hydrate. 

In 1971, a preparation of 1 from 2 using thallium cyclopentadienide was reported (I) but the toxicity of thallium and the mass of the reagent needed render this procedure unsuitable for large-scale preparations. An improved method was reported by Bruce et al. (3,4), using cyclopentadiene, ruthenium trichloride hydrate (3), and triphenylphosphine, which gives the desired complex in high yield [Eq. (2)]. The primary advantage of this latter method is formation of the complex in one pot. 

The early preparations gave poor yields but highly efficient methods have been developed recently. Optimum yields are obtained by the method of Pino and his coworkers9 in which tris(2,4-pentanedionato)ruthenium(III) is treated with equimolar mixtures of hydrogen and carbon monoxide at moderate temperatures and pressures (140-160°, 200-300 atmospheres). However, this method is limited by the availability of the tris-(2,4-pentanedionato)ruthenium(III) which is obtained in only low yields from the readily available ruthenium trichloride hydrate. The method given here is a modification on the Pino method. 

Ruthenium trichloride hydrate (5 g.), sodium acetylacetonate (7 g.), and methyl alcohol (140 ml.) are placed in the autoclave in that order. Hydrogen (40 atmospheres) and carbon monoxide (120 atmospheres) (i.e., total initial pressures = 160 atmospheres at room temperature) are then added and the reaction mixture heated at 165° for 4 hours. When cold the pressure is released and the crude orange crystalline dodecacarbonyltriruthenium separated by filtration. The mother liquor is evaporated to dryness and any additional product extracted into hot hexane in a Soxhlet apparatus. The combined products are then recrystallized from hot hexane, f Yields vary slightly from preparation to preparation but are usually in the range 50-55% (2.5 g.). (The checker obtained a yield of 3.0 g., 70%.)... 

The financial support of NSERC (Canada) and Carleton University is gratefully acknowledged. I would also like to thank NSERC (Canada) for the award of a University Research Fellowship and Johnson-Matthey P.L.C. for the loan of ruthenium trichloride hydrate in support of my research program. 

HYDROGENATION CATALYSTS Bis-(pyridine)dimethylformamidcdichlororbo-dium borohydride. Iron pentacarbonyl. Lindlar catalyst. Nickel boride. Palladium-on-calcium carbonate. Rhodium-on-alumina. Rhodium-on-carbon. Ruthenium trichloride hydrate. Triton dodecacar-bonyL Tris(tiiplienylpho ine)chloto-... 

The oxidation of alcohols with ruthenium tetroxide prepared by oxidation of ruthenium trichloride hydrate with sodium bromate takes place at room temperature. However, aldehydes may undergo further oxidation to carboxylic acids [940]. 

Besides ruthenium tetroxide, other ruthenium salts, such as ruthenium trichloride hydrate, may be used for oxidation of carbon-carbon double bonds. Addition of acetonitrile as a cosolvent to the carbon tetrachloride-water biphase system markedly improves the effectiveness and reliability of ruthenium-catalyzed oxidations. For example, RuCl3 H20 in conjunction with NaI04 in acetonitrile-CCl4-H20 oxidizes (Ej-S-decene to pentanoic acid in 88% yield. Ruthenium salts may also be employed for oxidations of primary alcohols to carboxylic acids, secondary alcohols to ketones, and 1,2-diols to carboxylic acids under mild conditions at room temperature, as exemplified below. However, in the absence of such readily oxidized functional groups, even aromatic rings are oxidized. 

Preparation. This oxotriruthenium acetate complex is obtained by treating ruthenium trichloride hydrate with acetic acid and sodium acetate in ethanol (1 hr. reflux). It can be purified by crystallization from methanol—acetone. 

The reactions of iron carbonyls with diorgano tellurides deserve mention, for example the reaction of Fe3(CO),2 with PhjTe gives Ph2TeFe(CO>4, whilst several ruthenium-carbonyl complexes have been prepared from reactions between diphenyl telluride and alcoholic carbon monoxide-saturated solutions of ruthenium trichloride hydrate. Various other ruthenium-carbonyl complexes of diorgano teUurides, including di- and tri-substituted species, have also been described. The utility of diphenyl telluride in transition metal carbonyl chemistry has also been well illustrated during studies of manganese and rhenium compounds. 

Figure 27 TEM image of a lamellar stack grown In a PET/PEI 20/80 blend crystallized for 9.5 h at 473 K. The microtomed section was exposed to vapors of a ruthenium trichloride hydrate/sodlum hypochlorite solution. The noncrystalline PET regions appear dark in the micrograph. With permission from Ivanov, D. Pop, T. Yoon, D. Jonas, A. Macromolecules 2002, 35, 9813. ...

Add 13 mg of ruthenium trichloride hydrate to the reaction mixture, stopper the flask, and stir the two-phase reaction vigorously for 2 h at room temperature. 

Ruthenium trichloride hydrate Is an Ill-defined mixture of ruthenium(lll) and (IV) compounds which... 

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