Preparation of Dehydro-L-ascorbic Acid in Ethanol and in Acetone by Using Silver Oxide as an Oxidant

Abstract

Oxidation of L-ascorbic acid to dehydro-L-ascorbic acid by use of silver oxide was conducted in ethanol and in acetone. Excess silver in the reaction mixture was removed by filtration with charcoal to avoid the reduction of formed de hydro-L-ascorbic acid by excess of hydrogen sulfide which has been used for silver removal. With this method, the yield of crystalline dehydro-L-ascorbic acid by the reaction in ethanol was 80%, and in acetone 55%.