Alcohols, primary with permanganates

This is not new information. We learned, during our study of the mild oxidation of alcohols (Sec. 13.5.3), that aldehydes undergo mild oxidation to carboxylic acids but ketones are resistant to mild oxidation. Mild oxidation of a primary alcohol with permanganate or dichromate proceeds initially to yield an aldehyde and then the aldehyde is oxidized to a carboxylic acid. Mild oxidation of a secondary alcohol yields a ketone which does not oxidize further. 

Any functional group that undergoes oxidation with permanganate interferes with the test (phenols, aryl amines, most aldehydes, primary and secondary alcohols, etc.). 

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

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. 

Primary and secondary alcohols are oxidized slowly at low temperatures by benzyltriethylammonium permanganate in dichloromethane primary alcohols produce methylene esters (60-70%), resulting from reaction of the initially formed carboxylate anion with the solvent, with minor amounts of the chloromethyl esters and the carboxylic acids. Secondary alcohols are oxidized (75-95%) to ketones [34] the yields compare favourably with those obtained using potassium permanganate on a solid support. 1,5-Diols are oxidized by potassium permanganate under phase-transfer catalytic conditions to yield 8,8-disubstituted-8-valerolactones [35] (Scheme 10.1). 

Acidified potassium permanganate solution, KMn04(aq), acts as an oxidizing agent when it comes in contact with alcohols. In this investigation, you will discover how potassium permanganate reacts with a primary, a secondary, and a tertiary alcohol. 

Primary alcohols are readUy oxidised to carboxylic acids with common oxidising agents such as potassium permanganate (KMn04) in neutral, acidic or alkaline media or by potassium dichromate (K2Cr207) and chromium trioxide (CrOg) in acidic media (Jones reagent). 

Benzyl alcohol readily undergoes the reactions characteristic of a primary alcohol, such as esterification and etherification, as well as halide formation. In addition, it undergoes ring substitution. In the presence of acid, polymerization is observed, and the alcohol can be thermally dehydrated to toluene [108-88-3], Catalytic oxidation over copper oxide yields benzaldehyde benzoic acid is obtained by oxidation with chromic acid or potassium permanganate. Catalytic hydrogenation of the ring gives cyclohexylmethanol [100-49-2]. 

Permanganate ion, Mn04G, oxidizes both primary and secondary alcohols in either basic or acidic solution. With primary alcohols the product normally is the carboxylic acid because the intermediate aldehyde is oxidized rapidly by permanganate ... 

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