Electrochemical oxidation of 4-amino phenol in the presence of 2-mercaptobenzimidazoles and synthesis of new organosulfur compounds

Abstract

In this research, the electrochemical oxidation of 4-amino phenol (1) was studied by cyclic voltammetry and controlled potential coulometryin in the absence and presence of 2-mercaptobenzimidazole (3a), 2-mercapto-5-methyl benzimidazole (3b) and 2-mercapto-5-metoxy benzimidazole (3c) in aqueous/ethanol (70/30 v/v) mixture.The results revealed that p-quinone(2) derived from oxidation of 4-amino phenol (1) participate in Michaeladdition reactions with 3a-c via EC mechanism. To confirm the proposed mechanism, the electrochemical synthesis of 4-amino phenol (1) was performed in the presence of 2-mercapto benzimidazoles (3a-c), and the obtained products were identified by 1HNMR, FTIR and Mass spectroscopy. In this study, we synthesized a variety of products with good efficiency using controlled potential electrochemical oxidation at a surface of graphite electrode.

Keywords

• 4-aminophenol
• ؛ 2-mercaptobenzimidazoles؛ cyclic voltammetry؛ michael addition reactions