Cyclic Voltammetry and Electron Paramagnetic Resonance Study of the Electrochemical Reduction of P-Nitrobenzyl Bromide in Aprotic Solvents

Abstract

EPR has been used to investigate the radicals postulated as intermediates in the intramolecular electron transfer and dehalogenation of p-nitrobenzyl bromide (p-NBBr) in DMSO and DMFA at room temperature. The electrochemical behavior has been studied through the use of cyclic voltammetry. According to the postulated reaction mechanism, the one-electron reduction of p-nitrobenzyl bromide generates an anion radical which undergoes breakage of the C-Br bond followed by intramolecular electron transfer. The free radical obtained is finally transformed into p-nitrotoluene.

Key Words:

• Nitro radical
• EPR
• electrochemical reduction
• aprotic solvents
• electron-transfer