Anodic Oxidation of Caffeine and Theophylline in Glacial Acetic Acid

Abstract

Abstract The anodic oxidation of caffeine and theophylline has been carried out at a controlled potential in a one compartment cell using glassy‐carbon as the anode, platinum as the cathode and glacial acetic acid/sodium acetate as solvent‐supporting‐electrolyte (SSE). The oxidation of caffeine yields 1,3,8‐trimethyl‐1,3,6,8‐tetrazaspiro[4.4]nonane‐2,4,7,9‐tetrone and (4‐acetoxy‐1,3,7‐trimethyl‐2,6,8‐trioxo‐9H‐purin‐5‐yl) acetate . Despite of the different structure, the oxidation of theophylline leads only to the same spiro compound 1,3,8‐trimethyl‐1,3,6,8‐tetrazaspiro[4.4]nonane‐2,4,7,9‐tetrone as in the case of caffeine. The structure of both compounds is described and the reaction mechanism is discussed.