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Ruthenium tetroxide

Ruthenium tetroxide is known to be a stronger oxidizing agent than osmium tetroxide and supposedly superior for staining rubber [209]. This chemical oxidizes aromatic rings yielding either mono- or dicarboxylic acids [210]. Although osmium tetroxide was the more predominant [Pg.166]

The general method for ruthenium tetroxide staining is to stain sections over a fresh 1% solution for about 5-30 min. This is a problem as RUO4 solutions are quite unstable, though Trent et al. [212] have frozen solutions in sealed glass containers for periods up to 6 months and report that ruthenium tetroxide can be prepared by oxidation of hydrated ruthenium dioxide using sodium periodate (available from [Pg.169]

Transmission electron microscopy images of latex particles prepared by staining with OSO4, RUO4, and phosphotungstic acid [225] are found [Pg.171]

In summary, RUO4 is an oxidizing agent that appears somewhat similar to OSO4 in the staining of unsaturated phases. Some saturated polymers may be stained with this reagent by vapor phase reaction of sections for short times (30 min). Although the reactive moieties appear to include ethers, edcohols, aromatics, and [Pg.172]

Preparation of Ruthenium Tetroxide Solution. Ruthenium dioxide (0.4 g) is suspended in 50 ml carbon tetrachloride. A solution of 3.2 g sodium metaperiodate in 50 ml water is added and the mixture stirred 1 hr at 0°. The black ruthenium dioxide gradually dissolves. [Pg.243]

The clear yellow carbon tetrachloride layer is separated and filtered through glass wool to remove insoluble materials. To the solution in a separatory funnel, fresh sodium metaperiodate solution (1.0 g/50 ml) is added. The mixture is shaken until the yellow color of the carbon tetrachloride phase persists and then it is stored in a cold place. [Pg.243]

5oc-Androstane-3,17-dione. A solution of 0.3 g (1.02 mmoles) 3a-hy-droxy-5a-androstan-17-one in 30 ml carbon tetrachloride is covered with 2 ml water and stirred. The solution of ruthenium tetroxide is added dropwise [Pg.243]

5a-Androstane-3,17-dione—Catalytic Oxidation with Ruthenium Tetrox-ide-Sodium Metaperiodate/A solution of 0.29 g (1.01) mmoles) 3 -hy-droxy-5a-androstan-17-one in 50 ml carbon tetrachloride is mixed with 15 ml (1.5 mmoles) of aq sodium metaperiodate (2.14 g/100 ml). To this mixture is added 2.7 ml of 0.037 Af ruthenium tetroxide solution (0.1 mmole, 10 mole %) and the mixture is shaken vigorously (3 hr at room temp). The carbon tetrachloride layer is separated and a small amount of 2-propanol added to destroy the excess reagent. The ruthenium dioxide is removed by filtration and the solvent evaporated in vacuo. The residue is crystallized from hexane to yield 0.24 g (82%) of 5a-androstane-3,17-dione mp 132-133°. [Pg.244]

Trent et al. [142-144] have been responsible for introducing ruthenium tetroxide stain for the electron microscopy of polystyrene/pol57(methyl [Pg.104]

This latter, one step procedure was applied [148] to PE films and blends of PE and PP with elastomers. Treatment times of 30 min to 3h were followed by drying and embedding in Spurr epoxy resin for ultramicrotomy. Care must be taken as ruthenicm tetroxide is volatile and toxic although little is known regarding health hazards. The expected reaction of unsaturated chains with ruthenium tetroxide is given by [Pg.105]

A section of a nylon blend with a saturated elastomer was prepared by room temperature microtomy with no staining, as shown in the STEM image (Fig. 4.17A). Unfortunately, the section [Pg.105]

However, some flammable solvents such as cyclohexane may be suitable for some [Pg.220]

In fact, the description by Nakata of the use of catalytic Ru04 in the oxidation of alcohols is predated by an article by Pappo and Becker30b in 1956, that is seldom cited because it was published in a journal of limited distribution. [Pg.221]

Although NaI04 or KI04 are the secondary oxidants used in the vast majority of cases in which alcohols are oxidized with catalytic Ru04, the employment of sodium hypochlorite (NaOCl),31 sodium bromate (NaBrOj )32 or Cl+, electrolytic-ally generated by oxidation of chloride ion,33 have also been reported. [Pg.221]

Morris Jr. and Kiely37 in 1987 noted a great acceleration in the oxidation of alcohols, with catalytic Ru04 in a biphasic system, upon addition of 1% molar benzyltriethylammonium chloride (BTEAC) as a phase-transfer catalyst. [Pg.221]

One molecule of Ru04 is able to oxidize two molecules of a secondary alcohol to the corresponding ketone, while Ru04 is transformed into Ru02. Mechanistic evidences show that the rate determining step involves a hydride transfer from the alcohol to the oxidant as in the following Equation.39 [Pg.222]

Hobbs et ah [173-174] have studied the morphology and toughening mechanisms of toughened blends of poly(butylene terephtha- [Pg.114]

ASA and nylon 11 HOPE and PP are only lightly stained by this method. [Pg.119]


Internal alkynes are oxidized to acytoins by thalliuin(III) in acidic solution (A. McKil-lop, 1973 G.W. Rotermund, 1975) or to 1,2-diketones by permanganate or by in situ generated ruthenium tetroxide (D.G. Lee, 1969, 1973 H. Gopal, 1971). Terminal alkynes undergo oxidative degradation to carboxylic acids with loss of the terminal carbon atom with these oxidants. [Pg.132]

The conversion of primary alcohols and aldehydes into carboxylic acids is generally possible with all strong oxidants. Silver(II) oxide in THF/water is particularly useful as a neutral oxidant (E.J. Corey, 1968 A). The direct conversion of primary alcohols into carboxylic esters is achieved with MnOj in the presence of hydrogen cyanide and alcohols (E.J. Corey, 1968 A,D). The remarkably smooth oxidation of ethers to esters by ruthenium tetroxide has been employed quite often (D.G. Lee, 1973). Dibutyl ether affords butyl butanoate, and tetra-hydrofuran yields butyrolactone almost quantitatively. More complex educts also give acceptable yields (M.E. Wolff, 1963). [Pg.134]

Phosphorus tribromide Potassium, ruthenium tetroxide, sodium, water... [Pg.1211]

Thus, Mathis et al. [1, 2] investigated oxidation reactions with 4-nitroperbenzoic acid, sodium hypobromite, osmium tetroxide and ruthenium tetroxide. Hamann et al. [3] employed phosphorus oxychloride in pyridine for dehydration. However, this method is accompanied by the disadvantages that the volume applied is increased because reagent has been added and that water is sometimes produced in the reaction and has to be removed before the chromatographic separation. [Pg.55]

Oxidation of a mixture of perfluorononene isomers to a mixture of per-fluorocarboxylic acids is accomplished with two agents, potassium permanganate and ruthenium tetroxide. Oxidation with potassium permanganate is slower and gives lower yields than oxidation with ruthenium tetroxide [40] (equation 32). [Pg.332]

Conversion of l,6-anhydro-4-0-benzyl-2 deoxy 2-fluoro-p-D-glucopyranose to the corresponding oxo derivative is earned out by ruthenium tetroxide generated in situ from ruthenium dioxide [54] (equation 49)... [Pg.336]

A. m-Butyl Butyrate from Di- -butyl Ether by Ruthenium Tetroxide... [Pg.12]

Preparation of Ruthenium Tetroxide (/5) In a 250-ml flask equipped with a magnetic stirrer and cooled in an ice-salt bath is placed a mixture of 0.4 g of ruthenium dioxide and 50 ml of carbon tetrachloride. A solution of 3.2 g of sodium metaperiodate in 50 ml of water is added and the mixture is stirred 1 hour at 0°. The black ruthenium dioxide gradually dissolves. The clear yellow carbon tetrachloride layer is separated and filtered through glass wool to remove insoluble materials. The solution may be used immediately or stored in the cold in the presence of 50 ml of sodium metaperiodate solution (1 g/50 ml). As prepared above, the solution is about 0.037 M in ruthenium tetroxide and contains 0.3 g/50 ml. [Pg.13]

The sequence has been applied to the synthesis of 1,4-cyclohexanedione from hydroquinone 10), using W-7 Raney nickel as prepared by Billica and Adkins 6), except that the catalyst was stored under water. The use of water as solvent permitted, after hltration of the catalyst, direct oxidation of the reaction mixture with ruthenium trichloride and sodium hypochlorite via ruthenium tetroxide 78). Hydroquinone can be reduced to the diol over /o Rh-on-C at ambient conditions quantitatively (20). [Pg.129]

Fortunately, the oxidation of l,2 5,6-di-0-isopropylidene-a-D-glucofura-nose to l,2 5,6-di-0-isopropylidene-a-D-nfoo-hexofuranos-3-ulose (1) can be accomplished using either phosphorus pentoxide (10, 44) or acetic anhydride (10, 52) in methyl sulfoxide although this oxidation is effected with ruthenium tetroxide (6,7, 46), it is exceeding difficult with other oxidizing agents (53). Keto-sugar 1 is reduced stereospecifically... [Pg.68]

By monitoring the intensity of the carbonyl absorption it was observed that oxidation of methyl 4,6-0-benzylidene-2-deoxy-a-D-Zt/ ro-hexopyrano-side with chromium trioxide-pyridine at room temperature gave initially the hexopyranosid-3-ulose (2) in low concentration, but attempts to increase this yield resulted in elimination of methanol to give compound 3. However, when methyl 4,6-0-benzylidene-2-deoxy-a-D-Zt/ ro-hexo-pyranoside is oxidized by ruthenium tetroxide in either carbon tetrachloride or methylene dichloride it affords compound 2 without concomitant elimination. When compound 2 was heated for 30 minutes in pyridine which was 0.1 M in either perchloric acid or hydrochloric acid it afforded compound 3, but in pyridine alone it was recoverable unchanged (2). Another example of this type of elimination, leading to the introduction of unsaturation into a glycopyranoid ring, was observed... [Pg.151]

From the reaction of 5-0-benzoyl-l,2-0-isopropylidene-o -D-en/t/iro-pentofuranos-3-ulose (prepared in 80% yield by oxidation of 5-0-benzoyl-l,2-0-isopropylidene- -D-xylofuranose (35,36) with ruthenium tetroxide) with an excess of diazomethane in methanol-ether, two main products (m.p. 44°-45°C. and 76°-77°C.), both epoxides, could be isolated by chromatography of the product on a silica column. An... [Pg.154]

Almost all the materials which are being considered as components in automobile exhaust catalyst are somewhat toxic (74)- Most of the compounds considered are low vapor pressure solids which can only escape from the exhaust system as very fine airbone dust particles formed by catalyst attrition. A few compounds, such as the highly toxic metal carbonyls and ruthenium tetroxides, are liquid under ambient conditions and have boiling points less than 100 °C. These compounds are not present in... [Pg.81]

If a mixture of diphenyl sulphide and the corresponding sulphoxide are treated with osmium tetroxide in boiling ether for 48 hours the sulphide is unchanged whilst the sulphoxide is converted into the sulphone in 96% yield with concomitant production of osmium trioxide140. It thus seems that this method would be useful synthetically for the preparation of sulphones from sulphoxides containing sulphide functionalities. Ruthenium tetroxide may be used in place of osmium(VIII) oxide148. [Pg.985]

A novel oxidation of sulphilimines using ruthenium tetroxide (generated in situ from ruthenium dioxide in a two-phase system) for the preparation of sulphoximines has been reported and proceeds in yields greater than 85%185. [Pg.990]

Hydroxy-5-oxo-3,5-seco-4-norandrostane-3-carboxylic acid has been prepared by ozonolysis of testosterone2-4 or of testosterone acetate, followed by alkaline hydrolysis,5 and by the oxidation of testosterone acetate with ruthenium tetroxide.9... [Pg.69]


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Alcohols oxidation with ruthenium tetroxide

Alcohols ruthenium tetroxide

Alcohols, primary with ruthenium tetroxide

Alcohols, secondary, oxidation with ruthenium tetroxide

Alkenes ruthenium tetroxide

Alkenes, reaction with ruthenium tetroxide

Alkynes ruthenium tetroxide

Amides Ruthenium tetroxide

Carboxylic acids with ruthenium tetroxide

Cyclohexene ruthenium tetroxide

Esters with ruthenium tetroxide

Ethers oxidation with ruthenium tetroxide

Lactams Ruthenium tetroxide

Oxidation amine, ruthenium tetroxide

Oxidation with ruthenium tetroxide

Oxidative cleavage with ruthenium tetroxide

Polynuclear aromatic hydrocarbons ruthenium tetroxide

Preparation of ruthenium tetroxide solution

Ruthenium alloys tetroxide

Ruthenium tetroxide (RuO

Ruthenium tetroxide 5 states

Ruthenium tetroxide as oxidant

Ruthenium tetroxide asymmetric dihydroxylation

Ruthenium tetroxide benzyl ethers

Ruthenium tetroxide benzyl methyl ether

Ruthenium tetroxide catalyst

Ruthenium tetroxide complexes

Ruthenium tetroxide ethers

Ruthenium tetroxide oxidation

Ruthenium tetroxide oxidation mechanism

Ruthenium tetroxide oxidation sensitivity

Ruthenium tetroxide oxidative cleavage of alkenes

Ruthenium tetroxide preparation

Ruthenium tetroxide properties

Ruthenium tetroxide reaction conditions

Ruthenium tetroxide reaction with solvents

Ruthenium tetroxide solvents

Ruthenium tetroxide staining

Ruthenium tetroxide staining method

Ruthenium tetroxide synthesis of carbonyl compounds

Ruthenium tetroxide synthesis of carboxylic acids

Tetroxides

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