Oxidation of primary alcohols to carboxylic acids

The oxidation of primary alcohols to carboxylic acids is an important oxidation reaction in organic chemistry.

When a primary alcohol is converted to a carboxylic acid, the terminal carbon atom increases its oxidation state by four. Oxidants able to perform this operation in complex organic molecules, featuring other oxidation-sensitive functional groups, must possess substantial selectivity. The most common oxidants are potassium permanganate (KMnO₄), Jones reagent, PDC in DMF, Heyns oxidation, ruthenium tetroxide (RuO₄) and TEMPO.

Potassium permanganate

Potassium permanganate (KMnO₄) is a very strong oxidant able to react with many functional groups, such as secondary alcohols, 1,2-diols, aldehydes, alkenes, oximes, sulfides and thiols. Under controlled conditions, KMnO₄ oxidizes very efficiently primary alcohols to carboxylic acids. This reaction, which was first described in detail by Fournier, to a solution or suspension of the alcohol in an alkaline aqueous solution. The resulting mixture is stirred till the oxidation is complete. For the reaction to proceed efficiently, the alcohol must be at least partially dissolved in the aqueous solution. This can be facilitated by the addition of an organic co-solvent such as dioxane, pyridine, acetone or t-BuOH....
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