Chitosan – hydrogen iodide salt supported graphite electrode: A simple and novel electrode for the reduction of nitro group under electrochemical condition

Abstract

The present investigation provides a unique, simple, selective and efficient method for the electrochemical reduction of aromatic nitro groups into amines using chitosan-hydrogen iodide salt supported graphite electrode. 3:1 tetrabutyl ammonium chloride and acetic acid mixture was used as the medium for electrolytic process and a constant voltage of 5 V applied between the modified electrodes. The reaction was found to be selective and further reduction of amines was not observed. The purity of the products was checked with HPLC and characterized using spectroscopic tools. The electrochemical synthesis resulted in moderate to good yields of amino compounds which were higher than the reduction using conventional graphite electrodes. Quaternary ammonium chloride behaved as supporting electrolyte during synthesis and the reaction did not progress in the absence of acetic acid. The redox characteristic of the process was studied by cyclic voltammetry of the reaction mixture.