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Oxidation with sodium peroxide

Other methods—iu all of which the resultant sulphate is precipitated with barium chloride—for the detection of sulphur in compounds, are (a) oxidation with sodium peroxide (see p. 472) (b) oxidation with sodium carbonate and potassium nitrate (c) oxidation with fuming nitric acid in sealed tubes. [Pg.445]

Iodine is determined by igniting a sample in air with the full flame of a Bunsen burner and comparing the weight of the chromium(III) oxide produced with the initial weight of the sample. Chromium is determined in the usual manner by fusing the oxide with sodium peroxide and measuring the quantity of chromate ion produced. Anal. Calcd. for Crl3 Cr, 12.02 I, 87.98. Found Cr, 12.03, 11.73 I, 85.47, 87.65. [Pg.129]

Ruthenium catalysts146 consist of the finely divided metal or of their oxides or salts which may be suspended on carriers (wood charcoal, silica gel, and the like). A useful method is to melt ruthenium metal or its oxide with sodium peroxide and to place the solution of the salt obtained on to the carrier. [Pg.21]

The chromates of the alkali metals and of magnesium and calcium are soluble in water the other chromates are insoluble. The chromate ion is yellow, but some insoluble chromates are red (for example silver chromate, Ag2Cr04). Chromates are often isomorph-ous with sulphates, which suggests that the chromate ion, CrO has a tetrahedral structure similar to that of the sulphate ion, SO4 Chromates may be prepared by oxidising chromium(III) salts the oxidation can be carried out by fusion with sodium peroxide, or by adding sodium peroxide to a solution of the chromium(IIl) salt. The use of sodium peroxide ensures an alkaline solution otherwise, under acid conditions, the chromate ion is converted into the orange-coloured dichromate ion ... [Pg.378]

Oxidation of 4 ten butylthiane (see Problem 16 23 for the structure of thiane) with sodium metaperiodate gives a mixture of two compounds of molecular formula CpHigOS Both products give the same sulfone on further oxidation with hydrogen peroxide What is the relationship between the two compounds ... [Pg.697]

Organic selenium compounds and siUceous materials (rock, ore, concentrates) are fused with mixtures of sodium carbonate and various oxidants, eg, sodium peroxide, potassium nitrate, or potassium persulfate. For volatile compounds, this fusion is performed in a bomb or a closed system microwave digestion vessel. An oxidizing fusion usually converts selenium into Se(VI) rather than Se(IV). [Pg.335]

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... [Pg.56]

In opocinchenine the hydroxyl group must, therefore, be in the ortho-position relative to the point of attachment of the benzene ring to the quinoline nucleus. The relative positions of the two ethyl groups are determined by the fact that apocincheninic acid ethyl ether on oxidation with lead peroxide and sulphuric acid gives the lactone of hydroxyopo-cincheninic acid ethyl ether (I), which, on oxidation by sodium hypo-bromite, yields quinolylphenetoledicarboxylic acid (II). [Pg.441]

A. Dry Process Discussion. The oxidation is carried out by fusion with sodium peroxide, or, less efficiently, with sodium carbonate and potassium nitrate ... [Pg.493]

For satisfactory whiteness on wool, it is essential for the fibre to be well scoured and bleached, either oxidatively with hydrogen peroxide or by reduction using stabilised sodium dithionite. Brightener is usually applied together with the dithionite bleach. To achieve the highest possible whiteness, the wool should first be scoured to remove natural waxes and other contaminants, then bleached with peroxide and finally treated with FBA during a second bleach with dithionite. [Pg.325]

Violence of reaction depends on concentration of acid and scale and proportion of reactants. The following observations were made with additions to 2-3 drops of ca. 90% acid. Nickel powder, becomes violent mercury, colloidal silver and thallium powder readily cause explosions zinc powder causes a violent explosion immediately. Iron powder is ineffective alone, but a trace of manganese dioxide promotes deflagration. Barium peroxide, copper(I) oxide, impure chromium trioxide, iridium dioxide, lead dioxide, manganese dioxide and vanadium pentoxide all cause violent decomposition, sometimes accelerating to explosion. Lead(II) oxide, lead(II),(IV) oxide and sodium peroxide all cause an immediate violent explosion. [Pg.172]

Impact sensitivities of mixtures of red phosphorus with various oxidants were determined in a direct drop-ball method, which indicated higher sensitivities than those determined with an indirect striker mechanism. Mixtures with silver chlorate were most sensitive, those with bromates, chlorates and chlorites were extremely sensitive, and mixtures with sodium peroxide and potassium superoxide were more sensitive than those with barium, calcium, magnesium, strontium or zinc peroxides. Mixtures with perchlorates or iodates had sensitivities comparable to those of unmixed explosives, such as lead azide, 3,5-dinitrobenzenediazonium-2-oxide etc. [Pg.1888]

SRP [Sulfonation-Reduction-Peroxide] A pulp-bleaching process which combines reduction with sodium borohydride and oxidation with hydrogen peroxide. Developed by Atochem in 1991 and licensed to Morton International, Chicago. [Pg.253]

For benzo[Z ]thiophene the heterocycle is rather more resistant to ring opening and oxidation with hydrogen peroxide in acetic acid at 95 C, for example, gives the 1,1-dioxide (Scheme 7.22) reduction with either sodium and ethanol or triethylsilane in trifluoroacetic acid affords 2,3-dihydrobenzo[Z)]thiophene. Electrophiles give mainly 3-substituted benzo[Z ]thiophenes, although these products are often accompanied by smaller amounts of the 2-isomers. [Pg.112]

Phenylacetamide has been obtained by a wide variety of reactions from benzyl cyanide with water at 250-260° 6 from benzyl cyanide with water and cadmium oxide at 240° 6 from benzyl cyanide with sulfuric acid 7 8 by saturation of an acetone solution of benzyl cyanide with potassium hydrosulfide 9 from benzyl cyanide with sodium peroxide 10 by electrolytic reduction of benzyl cyanide in sodium hydroxide 11 from ethyl phenyl-acetate with alcoholic 12 or aqueous 13 ammonia from phenyl-acetic acid with ammonium acetate 14 or urea 15 from diazoacetophenone with ammoniacal silver solution 16 from phenyl-acetic acid imino ether hydrochloride and water 17 from acetophenone with ammonium poly sulfide at 215° 18 from benzoic acid 19 and by heating the ammonium salt of phenyl-acetic acid.20... [Pg.94]

In general, sulfoximines are accessible by various routes, and most of them involve sulfur oxidation/imination sequences. For example, enantiopure 9 is commonly prepared starting from sulfide 10, which is oxidized with hydrogen peroxide (under acidic conditions) giving sulfoxide 11 (Scheme 2.1.1.1). Subsequent imina-tion of 11 with a mixture of sodium azide and sulfuric acid affords sulfoximine 9 as a racemate. Enantiomer resolution can then be achieved with camphorsul-fonic acid, leading to both enantiomers of 9 with high efficiency [15]. Alternatively, many sulfoximine syntheses start from enantiopure sulfoxides [16, 17], which can be stereospecifically iminated with 0-mesitylenesulfonylhydroxyl-amine (MSH) [18], as shown for the synthesis of sulfoximine (1 )-13 in Scheme 2.I.I.2. [Pg.151]

Synthesis (Krauli (E. Merck), 1925, Juby et al., 1968, Ehrhart and Ruschig 1972) Thebaine is oxidized with hydrogene peroxide to 14-hydroxycodeinone (Bentley 1954, Hauser 1974), which is hydrogenated directly or via its oxime, or its bromination products to oxycodone. The reduction of 14-hydroxycodeinone can also be carried out with sodium hydrosulfite. Alternatively 14-hydroxycodeinone is prepared by oxidation of codeine. [Pg.215]

Oxidation of Sugars in Alkaline Solutions with Sodium Peroxide... [Pg.87]

Additional results showed that spectra of the condensed lignosulfonate reduced with sodium bisulfite or zinc powder in hydrochloric acid approached the visible spectrum of the uncondensed lignosulfonate, although, in all instances, possessing increased absorption. Oxidizing the reduced lignosulfonate with sodium peroxide destroyed some of the aromatic system. [Pg.104]

Asymmetric hydroboration of enamines with chiral diboranes, followed by oxidation with hydrogen peroxide, in aqueous sodium hydroxide, gives /1-amino alcohols in good yields and high ee (equation 29)153. The products of this reaction are useful in medicinal applications and as synthons for further synthetic elaboration. [Pg.715]


See other pages where Oxidation with sodium peroxide is mentioned: [Pg.237]    [Pg.205]    [Pg.516]    [Pg.237]    [Pg.205]    [Pg.516]    [Pg.288]    [Pg.315]    [Pg.182]    [Pg.214]    [Pg.112]    [Pg.343]    [Pg.74]    [Pg.275]    [Pg.292]    [Pg.299]    [Pg.204]    [Pg.288]    [Pg.315]    [Pg.14]    [Pg.78]    [Pg.1580]    [Pg.1776]    [Pg.1859]    [Pg.356]    [Pg.261]   
See also in sourсe #XX -- [ Pg.79 ]




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Oxidants peroxides

Oxidation peroxidation

Oxidation with peroxides

Oxides peroxides

Peroxidative oxidation

Peroxides oxidation

Sodium oxidation

Sodium oxidations with

Sodium oxide

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