Potassium permanganate basic

Sahcylaldehyde is readily oxidized, however, to sahcyhc acid by reaction with solutions of potassium permanganate, or aqueous silver oxide suspension. 4-Hydroxybenzaldehyde can be oxidized to 4-hydroxybenzoic acid with aqueous silver nitrate (44). Organic peracids, in basic organic solvents, can also be used for these transformations into benzoic acids (45). Another type of oxidation is the reaction of sahcylaldehyde with alkaline potassium persulfate, which yields 2,5-dihydroxybenzaldehyde (46). 

The MauIg Color Reaction. The procedure for this test consists basically of three sequential treatments of lignified material with 1% potassium permanganate, 3% hydrochloric acid, and concentrated ammonium hydroxide. A red-purple color develops for hardwoods and a brown color... 

A great number of transformations has been performed on narceine imide (116) by Czech researchers. Oxidation with potassium permanganate in acetone or with nitric acid caused the cleavage of the alkaloid, giving rise to hemipinic imide (127). A similar result was noted by Rdnsch (129,130) during Lemieux-Johnson oxidation of ene lactam 152 (129,130) in this reaction the basic component (156) was isolated as well. The use of hydrogen peroxide in acetone converted 116 to (Z)-narceine imide N-oxide, which under the action of acetic anhydride underwent N-dealkylation (135). 

Limiting the reaction to hydroxylation alone is often difficult but usually attempted by using cold, dilute, and basic solutions of potassium permanganate. 

Treating alkynes with ozone or with basic potassium permanganate leads to... 

Strongly basic antibiotics may be precipitated by formation of the coloured reineckate salt which may then be determined spectrophotometri-cally 65. Bickfordl66 dissolved the precipitated neomycin reineckate in acetone and has successfully used this procedure to assay neomycin extracted from topical formulations. Roushdi et al 73 preferred to oxidise the precipitate with potassium permanganate and then colorimetrically estimate the chromate produced with diphenylcarbazide. 

Oxidation of benzotriazoles and other fused triazoles by potassium permanganate is a well-established route to lif-triazole 4,5-dicarboxylic acid derivatives. Many of the triazolo[d]pyrimidines, synthesized as purine analogs, can be degraded to monocyclic triazoles by acidic or basic hydrolysis (in other triazolopyriraidines, however, the triazole ring is cleaved preferentially ), e.g. Scheme 24. 

Figure 10-32 shows one common reagent mixture (the Jones reagent — Cr03/H2S0yacetone). Another common procedure is a two-step reaction where basic potassium permanganate oxidizes the aldehyde to a carboxylate ion and the second step involves the acidification of the product to form the carboxylic acid. 

Strong oxidants such a hot basic potassium permanganate oxidize a ketone with an alteration of the carbon backbone. Figure 10-34 illustrates the oxidation of a ketone with permanganate followed by acidification to produce a carboxylic acid. The oxidation cleaves the carbon-carbon on one side of the carbonyl group. 

The synthesis of carboxylic acids by the oxidation of alkenes is a two-step process. In the first step, a hot basic potassium permanganate (KMnO ) solution oxidizes an alkene, and in the second step, the oxidized alkene is acidified. The process cleaves the Ccirbon backbone at the carbon-carbon double bond to produce two smaller carboxylic acid molecules. For example, oleic acid (CH3(CH2)yCH=CI-l(CI-l2)yCOOH) yields of mixture of nonanoic acid (CH3(CH2)7C00H) and nonadioic acid (HOOC(CH2)7COOH). 

Potassium periodate can be prepared by oxidation of potassium iodate with a powerful oxidizing agent such as potassium permanganate, chlorine or bromine in basic solution ... 

Both of the stereoisomeric DL-tetroses were obtained21 from 1,1-diethoxy-2-butyn-4-ol (18a). In two steps, involving acetylation of 18a and partial hydrogenation of the triple bond in derivative 18b, cis-4-acetoxy-l,l-diethoxy-2-butene (19) was prepared. ci.s-Hydroxylation of 19 with potassium permanganate, followed by acetylation, led to 20. Hydrolysis (basic, and then acidic) of the protecting groups yielded DL-erythrose (28%). 

Reaction of an alkene with hot basic potassium permanganate (KMn04) results in cleavage of the double bond, and formation of highly oxidized carbons. Therefore, unsubstituted carbon atoms become CO2, mono-substituted carbon atoms become carboxylates, and di-substituted carbon atoms become ketones. This can be used as a chemical test (known as the Baeyer test) for alkenes and alkynes, in which the purple colour of the KMn04 disappears, and a brown Mn02 residue is formed. 

Alkynes are oxidized to diketones by cold, dilute and basic potassium permanganate. 

Unsubstituted carbon atoms are oxidized to CO2, and mono-substituted carbon atoms to carboxylic acids. Therefore, oxidation of 1-butyne with hot basic potassium permanganate followed by acidification produces propionic acid and carbon dioxide. 

By treatment with sufficiently strong oxidising agents, such as chromic acid or potassium permanganate with hydrochloric or sulphuric acid, aqueous solutions of salts of basic tellurium are converted into solutions of telluric acid.17... 

Oxidation of 3-amino-1,2,4-triazine (39) with peracetic acid led to 3-amino-1,2,4-triazin-5-one (233) (79JHC555) while oxidation with permanganate gave the 3,5-dione (234) (79JHC1649). When 3-amino-5,6-dimethyl-l,2,4-triazine (235) was treated in basic or acidic medium with potassium permanganate the only isolated product was the 3-amino-6-methyl-... 

Overoxidation with permanganate is always a problem, but the relative reaction rates are very much a function of the pH of the reaction mixture and, in basic solution, potassium permanganate oxidizes unsaturated groups more rapidly than it oxidizes alcohols ... 

Exercise 15-32 Explain why oxidation of secondary alcohols with 180-labeled potassium permanganate produces an 1sO-containing ketone in acidic solution, but not in basic solution. 

A purple solution of aqueous potassium permanganate (KMn04) reacts with aqueous sodium sulfite (Na2SC>3) in basic solution to yield the green manganate ion (Mn042-) and sulfate ion (S042-). The unbalanced net ionic equation is... 

The final reaction in this section provides a method to prepare aromatic rings bonded to a carboxylic acid group. Because we do not have a direct way to attach this group, this procedure is very useful. The reaction is usually accomplished by oxidation of a methyl group to the carboxylic acid employing hot potassium permanganate in basic solution ... 

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