Potassium permanganate alcohol oxidization

The reaction of dodecamethylcyclohexasilane with potassium permanganate, chromic oxide, and potassium dichromate in acetic acid gives a series of homologous cyclic siloxanes (20). Nitrobenzene and hydrogen peroxide (30%) in either formic acid or tcrt-butyl alcohol were found to be less effective oxidizing agents. 

Potassium permanganate (KMn04) oxidizes alcohols, but is a less selective reagent than chromium(VI) reagents. Write a reasonable multistep mechanism involving a manganate ester that accounts for the oxidation of a secondary alcohol to a ketone. 

The solvent-free potassium permanganate promoted oxidation of alcohols into the corresponding carbonyl derivatives has been examined by Luu et al. (2008). Secondary alcohols were oxidized very efficiently to the corresponding ketones at ambient temperature by KMnO absorbed on a fourfold molar amount of copper (II) sulfate pentahydrate. The reaction rate was enhanced considerably by ultrasonic irradiation also, but drastically in the presence of microwave irradiation, may be due... 

Isobutyl alcohol, isobutanol, 2-methyl-propanol, isopropyl carbinol, Me2CHCH20H. B.p. 108°C. Occurs in fusel-oil. Oxidized by potassium permanganate to 2-methyl-propanoic acid dehydrated by strong sulphuric acid to 2-methylpropene. 

By oxidation of primary alcohols with alkaline potassium permanganate solution or with a dichromate and dilute sulphuric add, for example ... 

Potassium permanganate (KMn04) will also oxidize pri mary alcohols to carboxylic acids What is the oxidation state of manganese in KMn04 ... 

The use of sofid supports in conjunction with permanganate reactions leads to modification of the reactivity and selectivity of the oxidant. The use of an inert support, such as bentonite (see Clays), copper sulfate pentahydrate, molecular sieves (qv) (151), or sifica, results in an oxidant that does not react with alkenes, but can be used, for example, to convert alcohols to ketones (152). A sofid supported permanganate reagent, composed of copper sulfate pentahydrate and potassium permanganate (153), has been shown to readily convert secondary alcohols into ketones under mild conditions, and in contrast to traditional permanganate reactivity, the reagent does not react with double bonds (154). 

The purification of diethyl ether (see Chapter 4) is typical of liquid ethers. The most common contaminants are the alcohols or hydroxy compounds from which the ethers are prepared, their oxidation products (e.g. aldehydes), peroxides and water. Peroxides, aldehydes and alcohols can be removed by shaking with alkaline potassium permanganate solution for several hours, followed by washing with water, concentrated sulfuric acid [CARE], then water. After drying with calcium chloride, the ether is distilled. It is then dried with sodium or with lithium aluminium hydride, redistilled and given a final fractional distillation. The drying process should be repeated if necessary. 

Ketones are more stable to oxidation than aldehydes and can be purified from oxidisable impurities by refluxing with potassium permanganate until the colour persists, followed by shaking with sodium carbonate (to remove acidic impurities) and distilling. Traces of water can be removed with type 4A Linde molecular sieves. Ketones which are solids can be purified by crystallisation from alcohol, toluene, or petroleum ether, and are usually sufficiently volatile for sublimation in vacuum. Ketones can be further purified via their bisulfite, semicarbazone or oxime derivatives (vide supra). The bisulfite addition compounds are formed only by aldehydes and methyl ketones but they are readily hydrolysed in dilute acid or alkali. 

Oxidation of unsaturatedfluoro alcohols to dicarboxyhc acids by potassium permanganate is carnal out in acetone or m acetic acid [56] (equation 51)... 

Oxidation of primary alcohols (Section 15.10) Potassium permanganate and chromic acid convert primary alcohols to carboxylic acids by way of the corresponding aldehyde. 

Heterocyclic compounds that have water bound covalently across a C=N bond behave as secondary alcohols. When subjected to very gentle oxidative conditions, they are converted into the corresponding 0x0 compounds. Potassium permanganate in 0. IN sodium hydroxide at room temperature has been used to oxidize 2- and 6-hydroxypteri-dine to 2,4- and 6,7-dihydroxypteridine, respectively. In contrast, 4-hydroxypteridine was not attacked by this reagent even at 100°. Hydrogen peroxide in acid solution was used to oxidize quinazoline quinazoline 3-oxide 1,3,5-, 1,3,7-, and 1,3,8-triazanaphthalene and pteridine (which hydrate across the 3,4-double bond in the... 

When the terpene a-fenchene (isopinene) is hydrated by means of acetic and sulphuric acids, it yields an isomer of fenchyl alcohol, which is known as isofenchyl alcohol (q.v.), and which on oxidation yields iso-fenchone, as fenchyl alcohol yields fenchone. The two ketones, fenchone and isofenchone, are sharply differentiated by isofenchone yielding iso-fenchocamphoric acid, Cj Hj O, on oxidation with potassium permanganate, which is not the case with fenchone. According to Aschan,i the hydrocarbon found in turpentine oil, and known as /9-pinolene (or cyclo-fenchene—as he now proposes to name it), when hydrated in the usual manner, yields both fenchyl and isofenchyl alcohols, which on oxidation yield the ketones fenchone and isofenchone. According to Aschan the relationships of these bodies are expressed by the following formulae —... 

It yields a monobromide melting at 41°, a semi-carbazone melting at 220° to 221 °, and an oxime melting at 106°. When reduced with sodium and alcohol it yields a secondary alcohol, which forms large crystals melting at 51°. On oxidation by cold 3 per cent, solution of potassium permanganate it yields geronic acid, a keto-acid of the constitution—... 

On oxidation with potassium permanganate it yields henzoic acid, and on reduction with sodium and alcohol, it is converted into the tetrahydro-der vative CjgHj O. The constitution of this oxide is probably— ... 

Carboxylic acids can be prepared by oxidizing primary alcohols and aldehydes with a strong oxidizing agent, such as acidified aqueous potassium permanganate solution. In some cases, an alkyl group can be oxidized directly to a carboxyl group. This process is very important industrially. 

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