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Potassium acetate ferricyanide

Platinum catalyst for reductions, 15, 89 Potassium acetate, 13, 36 Potassium bichromate, 12, 64 Potassium ferricyanide, 16, 41... [Pg.52]

In the early oxidation nitration preparation of DNPOH, the yield is relatively low (59-63 %), the product needs further purification, there is formaldehyde condensation reaction and other serious problems. Jeong et al. [63] modified the oxidation nitration process to optimize the oxidation nitration conditions of silver nitrate, in which aqueous formaldehyde solution (mass fraction of 35 %) was used for hy-droxymethylation and its reaction conditions were optimized, and a yellow solid DNPOH was obtained after extraction with methylene chloride and distillation. The average yield of DNPOH was more than 90 % and the mass fraction was more than 97 %. Based on these results, Grakauskas et al. [40-42, 65] used potassium ferri-cyanide as catalyst and potassium persulfate as oxidant to synthesize DNPOH. In this method, with potassium(sodium) ferricyanide and over potassium(sodium) persulfate, nitrite substitution reaction of nitroethane with sodium nitrite occurred, and then further reacted with formaldehyde under basic conditions, and finally DNPOH was extracted out with ethyl acetate under acidic conditions. Product was obtained through potassium distillation. The reaction mechanism is ... [Pg.168]

Potassium Acetate Potassium Acid Sulfate Potassium Acid Tartrate Potassium Antimonate Potassium Bicarbonate Potassium Bichromate Potassium Bisulfate Potassium Bisulfite Potassium Bitartrate Potassium Borate Potassium Bromate Potassium Bromide Potassium Carbonate Potassium Chlorate Potassium Chloride Potassium Chromate Potassium Cyanide Potassium Dichromate Potassium Ferricyanide Potassium Ferrocyanide Potassium Fluoride Potassium Hexacyanoferrate (III) Potassium Hydrogen Carbonate Potassium Hydrogen Sulfate Potassium Hydrogen Sulfite Potassium Hydroxide Potassium Hypochlorite Potassium Hyposulfite Potassium lodate Potassium Iodide Potassium Manganate Potassium Nitrate Potassium Perborate Potassium Perchlorate Potassium Permanganate Potassium Peroxydisulfate Potassium Persulfate... [Pg.3479]

Again, as with pyridopyrimidines, the main reaction is oxidation of di- or poly-hydro derivatives to fully aromatic structures, often merely by air or oxygen. In some cases the reagent of choice is mercury(II) oxide, whilst other reagents used include sulfur, bromine, chloranil, chromium trioxide-acetic acid, hydrogen peroxide, and potassium ferricyanide, which also caused oxidative removal of a benzyl group in the transformation (306) (307)... [Pg.237]

A -Piperideine-N-oxide was obtained along with a dimeric product by oxidation of N-hydroxypiperidines with mercuric acetate or potassium ferricyanide (107-109). 2l -Pyrroline-N-oxide is formed by oxidation of N-ethylpyrrolidine with hydrogen peroxide with simultaneous formation of ethylene (110). [Pg.261]

Potassium ferricyanide in oxidative decarboxylation, 40, 86 Potassium permanganate for oxidation of (trialkylmethyl)amines to tri-alkylnitromethanes, 43,87 Pregnenolone acetate, conversion to 3/3-acetoxyetienic acid, 42, 5 Propane, 2,2-dibotoxy-, 42,1 Propargylsuccinic anhydride, by-product in addition of maleic anhydride to allcne, 43, 27... [Pg.121]

Manganese(III)-promoted radical cyclization of arylthioformanilides and a-benzoylthio-formanilides is a recently described microwave-assisted example for the synthesis of 2-arylbenzothiazoles and 2-benzoylbenzothiazoles. In this study, manganese triacetate is introduced as a new reagent to replace potassium ferricyanide or bromide. The 2-substituted benzothiazoles are generated in 6 min at 110°C imder microwave irradiation (300 W) in a domestic oven with no real control of the temperature (reflux of acetic acid) (Scheme 15). Conventional heating (oil bath) of the reaction at 110 °C for 6 h gave similar yields [16]. [Pg.69]

Reaction of 1 with excess 103 in toluene gives the mixed carbamate (104) in 21% yield after chromatography on silica gel. Reduction of the S—S bond present in this carbamate is accomplished with zinc dust in acetic acid to give the A(-(2 -mercaptoethyl) oxazolidinedione (105) in high yield. Dimerization of 105 is then achieved by reaction with excess aqueous potassium ferricyanide to give the disulfide (106). [Pg.177]

Ethyl (6-Methoxy-l,2-naphthoquinonyl-6) Cyanoacetate. The above naphthoquinone (21.7 g) is added to a solution of 500 cc of ethanol and 14 cc of ethyl cyanoacetate, followed by the addition of 32 cc triethylamine. A deep purple color will develop and the mixture should be swirled for 4 min to dissolve the quinone completely. A solution of 75.9 g of potassium ferricyanide in 320 cc of water is then added to the solution, causing a thick dark complex to form and separate. Redissolve by adding a soluhon of 24 g of sodium carbonate in 1,600 cc of water. Swirl or stir and filter through diatomaceous filter aid. Acidify the filtrate with 100 cc of 6 M sulfuric acid to precipitate 34.8 g of red-orange powder, which is oven dried at 70°. Reciystallize from ethyl acetate to get 19.3 g, mp 157-158.5°. The remaining filtrate is evaporated to a small bulk and reciystallization from ethyl acetate gives an additional 2.8 g of product. [Pg.92]

These kinetic experiments were carried out in microcuvettes at 25°C, which contained 25 nmoi reduced pyridine nucieotide, 50 nmoi potassium ferricyanide (added at zero time as the eiectron acceptor), 1 nmoi reductase in 0.2 ml 0.1 M Tris-acetate (pH 8.1) containing 1 mM EDTA. [Pg.401]

Oxidizing agents such as potassium ferricyanide, chlorine or bromine in acetic acid and iodine in aqueous bicarbonate react with benzamid-oxime to yield 3,5-diphenyl-5-amino-dihydrooxadiazole 41). [Pg.173]

The evidence for the formation of complex heteropoly-acids with tantalic acid is very comparable to that set forth in the case of niobic acid (see p. 165). Solutions of tantalates are readily hydrolysed in aqueous solution by boiling, and even more readily by the addition of mineral acids, acetic acid or succinic acid in the presence, however, of arsenious add, arsenic add, tartaric add or dtric add no precipitation of tantalic add takes place. Again, tincture of galls yields a yellow predpitate with solutions of tantalates which have been rendered feebly acid with sulphuric add this reaction does not, however, take place in the presence of ordinary tartaric add, racemic add or citric acid. Tartaric add also prevents the formation of the predpitates which are thrown down on the addition of potassium ferrocyanide or potassium ferricyanide to faintly acid solutions of tantalates, and hinders the precipitation of tantalic add from solutions in inorganic acids by the action of ammonia. In all these cases it is assumed that complex acids or their salts are produced, in consequence of which the usual reaction does not take place. [Pg.202]

When the secondary reaction cycle shown in Scheme 6D.3 was discovered, it became clear that an increase in the rate of hydrolysis of trioxogly colate 10 should reduce the role played by this cycle. The addition of nucleophiles such as acetate (tetraethylammonium acetate is used) to osmylations is known to facilitate hydrolysis of osmate esters. Addition of acetate ion to catalytic ADs by using NMO as cooxidant was found to improve the enantiomeric purity for some diols, presumably as a result of accelerated osmate ester hydrolysis [16]. The subsequent change to potassium ferricyanide as cooxidant appears to result in nearly complete avoidance of the secondary cycle (see Section 4.4.2.2.), but the turnover rate of the new catalytic cycle may still depend on the rate of hydrolysis of the osmate ester 9. The addition of a sulfonamide (usually methanesulfonamide) has been found to enhance the rate of hydrolysis for osmate esters derived from 1,2-disubstituted and trisubstituted olefins [29]. However, for reasons that are not yet understood, addition of a sulfon-amide to the catalytic AD of terminal olefins (i.e., monosubstituted and 1,1-disubstituted olefins) actually slows the overall rate of the reaction. Therefore, when called for, the sulfonamide is added to the reaction at the rate of one equivalent per equivalent of olefin. This enhancement in rate of osmate hydrolysis allows most sluggish dihydroxylation reactions to be mn at 0°C rather than at room temperature [29]. [Pg.371]

Distilled water at 125F/52C, 500.0ml Ferric ammonium citrate, 8.0g Potassium ferricyanide, 8.0 g Acetic acid, 28% solution, 265.0ml Distilled water to make 1.0 liter... [Pg.275]

Potassium ferricyanide, 75.Og Potassium bromide, 75.0g Potassium oxalate, 195.0g Acetic acid, 40.0 ml Water, 2.0 liters... [Pg.284]

Oxidation of JV-hydroxypiperidine with cupric acetate or potassium ferricyanide gives J1-piperideine 1-oxide (30) in addition to a dimer or trimer.184,185 Dehydrogenation of l-hydroxy-2-phenylpiperidine takes a similar course.189... [Pg.180]

With certain compounds, such as pyrazoline carboxylic acids and esters, potassium ferricyanide or silver nitrate has been used,509 and for those compounds unsubstituted on nitrogen, mercuric oxide or acetate.76 Lead dioxide has been successful for the oxidation of 1-alkyl-and 1-arylpyrazolines,9i 76,83 and in certain instances even chromic acid, but not hydrogen peroxide or silver oxide.76 See also L. Smith521 and Birkinshaw et al.b22... [Pg.387]

Procedure Transfer an accurately measured volume of the Test Solution, equivalent to about 100 mg of a-tocopherol, into a separator, and add 200 mL of water. Extract first with 75 mL, then with two 25-mL portions of ether, and combine the ether extracts in another separator. Add 20 mL of a 10% solution of potassium ferricyanide in a 1 125 sodium hydroxide solution to the ether solution, and shake for 3 min. Wash the ether solution with four 50-mL portions of water, discard the washings, and dry over anhydrous sodium sulfate. Evaporate the dried ether solution on a water bath under reduced pressure or in an atmosphere of nitrogen until about 7 or 8 mL remain, and then complete the evaporation, removing the last traces of ether without the application of heat. Immediately dissolve the residue in 5.0 mL of isooctane, and determine the optical rotation. Calculate the optical rotation [see Optical (Specific) Rotation, Appendix IIB], using as c the concentration of D-a-Tocopheryl Acetate, as determined in the Assay (above), in 100 mL of solution. [Pg.483]

The synthesis of bufotenine itself followed closely upon the proof of its structure. Hoshino and Shimodaira reduced the ethyl ester of 5-ethoxy-indole-3-acetic acid by the Bouveault-Blanc procedure to the corresponding primary alcohol, which was treated with phosphorus tribromide and then dimethylamine, to give the ethyl ether of bufotenine, which was demethylated with aluminum chloride (130). In a later synthesis, 2,5-dimethoxybenzyl cyanide (XXIII) was alkylated by Eisleb s method with dimethylaminoethyl chloride in the presence of sodamide to give l-(2,5-dimethoxyphenyl)-3-dimethylaminopropyl cyanide (XXIV), which was then hydrogenated over Haney nickel to yield 2-(2,5-di-methoxyphenyl)-4-dimethylaminobutylamine (XXV R = Me). De-methylation of this with hydrobromic acid, followed by oxidation of the product (XXV R = H) with potassium ferricyanide yielded bufotenine (XIX) via the related quinone (109). [Pg.18]

There are several salts that behave in this way at atmospheric temperatures, the more important being ammonium acetate potassium bromate, carbonate, cyanide, ferricyanide, ferrocyanide, iodate, and permanganate disodium hydrogen phosphate and sodium borate and carbonate.4 In the case of potassium chlorate the points L and S appear to be practically coincident, whilst for the majority of salts the point S lies somewhere to the left of L, namely at S —that is to say, saturation occurs before the limiting concentration is reached. Generally speaking, at the ordinary temperature, concentrated solutions of salts are less corrosive than distilled water—that is, the point S lies below the level of A, exceptions being 5 ammonium sulphate, aluminium... [Pg.73]


See other pages where Potassium acetate ferricyanide is mentioned: [Pg.76]    [Pg.76]    [Pg.134]    [Pg.40]    [Pg.138]    [Pg.99]    [Pg.115]    [Pg.489]    [Pg.44]    [Pg.266]    [Pg.268]    [Pg.11]    [Pg.212]    [Pg.234]    [Pg.280]    [Pg.740]    [Pg.51]    [Pg.409]    [Pg.76]    [Pg.464]    [Pg.91]    [Pg.130]    [Pg.409]    [Pg.138]    [Pg.348]   
See also in sourсe #XX -- [ Pg.243 ]




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