By Direct Oxidation of the Corresponding Hexoses

Yields of osones obtained by the oxidation of sugars by Fenton s reagent are low, and the osones are invariably contaminated both with starting material and with the products of further oxidation in consequence, the method has had only limited application.44 

Nicoll, Strause and Waring46 oxidized D-glucose and D-fructose in aqueous solution with excess cupric acetate at 50° for the purpose of ascertaining whether the general principles underlying the mechanism of carbohydrate oxidation in alkaline solutions are sufficient to explain the course of such oxidations in acid solutions. D-Glucosone was claimed to be one of the first products of oxidation the osone was not isolated, and, 

They showed that osone formation is accompanied by the production of formic acid, thought to arise from the oxidation of hydroxymethylene formed by rupture of IV. 

Weidenhagen48 further investigated this reaction he found that osone formation could become the main reaction if ethanol or methanol was used as a solvent, the cupric acetate was not in excess, and the reaction time was limited. Oxidation of D-glucose or D-fructose was reported to give a 40% yield of D-glucosone.14-46 

The oxidation of D-glucose with potassium persulfate occurs very slowly at room temperature the optimum temperature is 40°, but the yield of osone is very small.38 

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