Oxidative cleavage of olefins to ketones and carboxylic acids by the usual oxidants

Oxidative cleavage of olefins to ketones and carboxylic acids by the usual 

From a preparative point of view the commonest use of oxidative cleavage of olefins by the usual oxidizing agents is for preparation of ketones and, even more so, of carboxylic acids. Azelaic acid is obtained by permanganate oxidation of ricinoleic acid as follows 113 

Ricinoleic acid (240 g), dissolved in water (1600 ml) containing potassium hydroxide (64 g), is added in one portion to a solution of potassium permanganate (625 g) in water (7.5 1) at 35°. The temperature rises to 75°. After 0.5 hour s stirring the permanganate color has disappeared and the solution is then acidified with sulfuric acid and filtered hot from manganese oxides. These oxides are boiled with water, and the resulting extracts and the original filtrate are evaporated to 4 1. Azelaic acid crystallizes from the cooled solution and can be recrystallized from water it has m.p. 104-106° and the yield is 32-36% (48-56 g). 

Oxidative cleavage of cycloalkenes is an important reaction, usually affording co,a/-dicarboxylic acids e.g., adipic acid is formed on oxidation of cyclo-hexene by permanganate.114 If there is no hydrogen on one of the doubly bonded carbon atoms, the product is an oxo carboxylic acid, e.g., a pinonic acid from a-pinene 115 

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