Alcohol reaction with KMnO

Unfortunately, such selective oxidations were not possible because primary alcohols form small amounts of carboxylic acid under the reaction conditions these acids efficiently inhibit oxidation, thereby accounting for the apparent Inertness of primary alcohols. When a secondary alcohol was mixed with a primary alcohol, neither was oxidized by the solid reagent in good yield. An oxidation of a secondary alcohol over crystalline KMnO would immediately cease when octanolc acid was added in tiny amounts to the benzene. The octanolc acid presumably binds to "active sites" at the crystal surface and Impedes the reaction by an unknown mechanism. 

Dimethyl OfOHdkanedicarboxylates. a-Nitrocycloalkanones suffer ring scission on exposure to KjSjOg in methanol containing sulfuric acid. The dimethyl esters are obtained. Note the accessibility of CU-formylcarboxylic esters by sequential treatment of a-nitrocycloalkanones with alcoholic KOH and KMnO,-MgSO (Nef reaction). ... 

They worked out such reactions with alcohols also along with aldehydes (2007). Use of hydrogen peroxide and KMnO as oxidants for HjPV2MOjqO catalyzed oxidation of aromatic aldehydes to the corresponding carboxylic acids under mild conditions has been reported by Shojaei et al. (2011). This system provides an efficient, convenient and practical method for the oxidation of aromatic aldehydes. 

Our own experience with reactions on crystal surfaces has been confined to oxidations on solid KMnO, and NaMnO, (12). The work began with a curious observation in conflict with literature statements. We found that solid KMnO, stirred with a benzene solution of a secondary alcohol would oxidize the alcohol to a ketone. 

In addition, it was shown that CuS0,(H20)- mixed with the KMnO, accelerated the oxidation of secondary alcohols. The combination produced an oxidant which was capable of oxidizing alcohols to ketones in high yield and under mild conditions as shown in Table I. Perhaps the most useful feature of the reactions in Table I is the easy workup filtration of the solids and evaporation of the benzene give the product in a satisfactory state of purity. 

KMnO/i reacts primarily with the sulfuric acid to give dimanganese hepioxide the latter oxidises the alcohol in a highly exoihermic reaction and itself is converted to manganese dioxide Mn02. 

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