Sodium permanganate monohydrate oxidant

Sofid sodium permanganate monohydrate has been shown to be a selective synthetic reagent (156). It is typically used in hexane for the heterogeneous oxidation of aldehydes, alcohols, and sulfides. Synthetic methodology based on crystal surfaces exhibited greater selectivity, higher yield, and easier work-up as compared to aqueous permanganate reactions. 

Table II Oxidations by Solid a b Sodium Permanganate Monohydrate g w...

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. ... 

In nonaqueous media, the oxidation of alcohols to acids is accomplished in heterogeneous systems by refluxing primary alcohols with solid sodium permanganate monohydrate in hexane (equation 232). The reaction is applicable even to allylic alcohols [555]. 

Nickel peroxide. Oxoperoxobis(N-phenylbenzohydroxamato) molyb-denum(VI). Palladium(II) acetate-Tri-phenylphosphine. Palladium /-butyl peroxide trifluoroacetate. Periodic acid. Permonophosphoric acid. Potassium dichromate. Potassium hydrogen persulfate. Pyridinium dichromate. Ruthenium tetroxide. Selenium dioxide. Sodium hypochlorite. Titanium(IlI) chlo-ride-Hydrogen peroxide. Potassium nitrodisulfonate. Potassium peroxodi-sulfate. Pyridinium chlorochromate. Pyridinium chlorochromate-Hydrogen peroxide. Sodium permanganate monohydrate. Tetra-n-Butylammonium periodate. Thailium(III) acetate. Trimethyl-amine N-oxide. Triphenylmethylphos-phonium permanganate. 

Sodium permanganate, commercially available although more expensive than potassium permanganate (14), was found to be an even more potent oxidant. The monohydrate form (NaMnO. H.O) can be used as purchased to oxidize a variety of functionalities by stirring the solid with substrates dissolved in hexane or methylene chloride (Table II). The solid phase oxidation would seem particularly useful for small-scale reactions (< 1 gram substrate). 

Sodium permanganate, which is used as its monohydrate in solid form in refluxing dichloromethane or hexane, oxidizes allylic alcohols more slowly and in lower yields than the saturated alcohols. 2-Cyclohexen-l-ol, after a 24-h reflux in hexane, furnishes a 47% yield of the ketone, whereas cyclohexanol gives a 100% yield after 1.5 h [555]. 

The primary hydroxyl group in 2,3 4,6-diisopropylidene-L-sorbose was oxidized with sodium hypochlorite in the presence of NiCls by Weijlard, who obtained a 90% yield of 2,3 4,6-diisopropylidene-2-keto-L-gulonic acid monohydrate. This reaction is normally carried out with permanganate for the production of ascorbic acid, but a wartime shortage of this oxidant caused the consideration of chlorine as a substitute. Similar results were found by Beer and Preobrazhenskii in more concentrated solutions. The yield of product was lowered drastically when the concentration of sodium hydroxide was less than 30%, when the chlorine-sorbose molar ratio was less than 4.1 and when... 

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