Sodium permanganate carboxylic acids

Photolysis of J gives an isomeric compound K in 83% yield. Alkaline hydrolysis of K affords a hydroxy carboxylic acid L, C25H32O4. Treatment of K with silica gel in hexane yields M, C24H2g02. M is converted by sodium periodate-potassium permanganate to a mixture of N and O. What are the structures of K, L, and M ... 

Potassium permanganate (4.59 g) was then slowly added and the mixture stirred for 2 hours on an iced bath for 18 hours at ambient temperature. The solution was then treated with 720 ml of ethyl acetate, 540 ml of water, and sodium hydrogensulfite and the pH raised to 1 using 1.0 M hydrochloric acid. The organic layer was separated and washed three times with 1.0 M hydrochloric acid and then concentrated and the residue washed successively with 600 ml of water, 600 ml of methanol, and three times with 600 ml of water. The residue was then dissolved in THF and reprecipitated in excess methanol, dried, and 5.30 g of product isolated having an Mn of 13,200 Da with an Mw of 18,300 Da and containing 8 mol% carboxylic acid. 

During an alkaline oxygen stage the formation of keto structures by oxidation of ketols is postulated, finally leading to acids. Sodium permanganate treatments yield a moderate increase in both, carbonyls and carboxyl groups at short reaction times [20]. 

The resistance of the furoxan ring to chemical attack allows derivatives to be prepared via the reactions of the substituents (Section 4.22.3.4). Carboxylic acids are available by permanganate oxidation of methyl derivatives or by hydrolysis of the corresponding esters reaction with ammonia affords carboxamides. Acylfuroxans provide a source of hydroxyalkyl compounds by reduction, and oximes, for example, via nucleophilic addition. Acylation and oxidation of aminofuroxans allows the amide and nitro derivatives to be prepared. Nucleophilic displacements of nitro substituents can take place, but can be somewhat hazardous on account of the explosive nature of these compounds. Alkoxy derivatives are formed with sodium alkoxide, while reaction with thiolate anions yields sulfides, from which sulfones can be synthesized by peracid oxidation. Nitrofuroxans have also been reduced to... 

Unlike ketones, aldehydes are easily oxidized to carboxylic acids by common oxidants such as bleach (sodium hypochlorite), chromic acid, permanganate, and peroxy Oxidation acids. Aldehydes oxidize so easily that air must be excluded from their containers to q-P A (jehvdeS avoid slow oxidation by atmospheric oxygen. Because aldehydes oxidize so easily, mild reagents such as Ag20 can oxidize them selectively in the presence of other oxidizable functional groups. 

Sodium periodate, used along with catalytic amounts of osmium tetroxide, radienium dioxide or potassium permanganatt, can also be employed to cleave carbon-carbon double bonds. When used with osmium tetroxide, carbonyls are produced however, the presence of permanganate results in the formation of more highly oxidized products (carboxylic acids) finom secondary carbons. 

The conversion of tetrasubstituted double bonds to the corresponding ketones is easily achieved using a number of oxidants. However, if one or more of the alkenic carbons is secondary, the product will be either an aldehyde or a carboxylic acid Ozone and a combination of osmium tetroxide and sodium metaperiodate are recommended if the desired product is an aldehyde. Under carefully controlled conditions it is also possible to obtain good yields of the aldehyde when permanganate is used as the oxidant All methods that give aldehydes from secondary carbons can also be used to prepare ketones from tertiary carbons. 

Sodium hypochlorite has been used to oxidize 10-alkylphenothia-zine-3-carboxylic acids to the 5,5-dioxides. Potassium permanganate also yields dioxides. - ... 

The products of the oxidation reactions can be used to distinguish between primary, secondary and tertiary alcohols. A primary alcohol undergoes a two-stage oxidation via an aldehyde to a carboxylic acid, whilst a secondary alcohol gives a ketone. Tertiary alcohols do not react under mild conditions. Potassium permanganate can also be used to oxidize alcohols. 1,2-Diols are oxidized specifically by sodium periodate. 

Oxidation of the pyrazole carboxaldehydes 294 using potassium permanganate in aqueous pyridine gave satisfactory yields of the carboxylic acids 295 (Equation 56) <2001CHE467>. Condensation of AT-alkylpyrazole-4-carbaldehyde 296 with 2,3-bis(hydroxyamino)-2,3-dimethylbutane sulfate, then sodium periodate oxidation of 1,3-dihydroxyimi-dazolidine 297 afforded pyrazolyl nitronyl nitroxides 298 (Scheme 26) <2001ARK55>. Another approach to... 

Sodium periodate (sodium metaperiodate), NaI04 (mp 300 °C dec), which is commercially available, is applied mainly in aqueous or aqueous-alcoholic solutions. Like the free periodic acid, sodium periodate cleaves vicinal diols to carbonyl compounds [762], This reaction is especially useful in connection with potassium permanganate [763, 764] or osmium tetroxide [765], Such mixed oxidants oxidize alkenes to carbonyl compounds or carboxylic acids, evidently by way of vicinal diols as intermediates. Sulfides are transformed by sodium periodate into sulfoxides [322, 323, 766, 767, 768, 769, 770, 771, 772], and selenides are converted into selenoxides [773]. Sodium periodate is also a reoxidant of lower valency ruthenium in oxidations with ruthenium tetroxide [567, 774],... 

Sodium permanganate monohydrate, NaMn04 H20, which is commercially available, is used for the oxidation of alkenes to carboxylic acids [834] and of alcohols to carbonyl compounds [SJ5], the conversion of sul-finic acids into sulfonic acids [836], and the selective oxidation of sulfoxides to sulfones (sulfides are not oxidized with sodium permanganate in dioxane solutions) 837. ... 

On treatment with potassium permanganate, the sodium salt of tol-uene-o-sulfonamide yields the corresponding carboxylic acid, which cy-clizes to form saccharin (equation 186) [1131],... 

Hydroxylation at double bonds of unsaturated carboxylic acids is accomplished stereoselectively by the same reagents as those used to hy-droxylate alkenes. syn Hydroxylation is carried out with potassium permanganate [101] or osmium tetroxide with hydrogen peroxide [130], sodium chlorate [310, 715], potassium chlorate [715], or silver chlorate [310] as reoxidant, anti Hydroxylation is achieved with peroxyacids, such as peroxybenzoic acid [310] or peroxyformic acid, prepared in situ from hydrogen peroxide and formic acid [101] (equation 472). 

Degradative oxidation of unsaturated carboxylic acids leads either to aldehydes or to dicarboxylic acids. In the presence of sodium carbonate and benzene, o-nitrocinnamic acid is oxidized with potassium permanganate at 10 °C to o-nitrobenzaldehyde in 64% isolated yield [842]. 

Hydroxy carboxylic acids and their esters are oxidized to keto acids and their esters, respectively. o-Nitromandelic acid is oxidized to o-nitro-phenylglyoxylic acid with a dilute solution of potassium permanganate at room temperature in 54% yield [886], The oxidation-of ethyl 3-hydroxy-cyclobutanecarboxylate with ruthenium tetroxide and sodium periodate in... 

Benzoic acid prepared catalytically from phthalic anhydride may contain certain undesirable compounds, tars, and coloring materials and must of necessity be purified in some cases to obtain a marketable product. Naphthoquinone impurities are reduced to naphthohydroquinones by treatment of the product with sulfur dioxide or sodium bisulfite at 40° to 50° C. for 3 to 4 hours. Any phthalic anhydride remaining is converted to phthalic acid at the same time. Leaching with water is used to remove the reduced impurities.72 Unconverted phthalic acid may also be separated from benzoic by treatment of the mass with sodium carbonate so as to convert the polycarboxylic acid into a primary salt while leaving the mono-carboxylic acid unreacted. Solvent leaching is then used to separate the salt from the acid.78 Colored impurities in benzoates from synthetic benzoic acid may be removed by oxidation with potassium permanganate.71... 

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