Efficient electrosynthesis of new mono- and bis-sulfonamide derivatives via electrooxidation of o-tolidine

Abstract

This work is the first documentation on synthesizing new mono- and bis-sulfonamide derivatives with o-tolidine (3,3′-dimethylbenzidine) in the central core. Using o-tolidine as a substrate and its electrochemical oxidation as well as the subsequent nucleophilic addition reaction between the oxidized o-tolidine and sulfinic acid derivatives, new mono- and bis-sulfonamide derivatives were synthesized in a solution of acetonitrile/water (30/70 v/v) at pH = 2.0 in 32–73% yields. The chemical structures of all synthesized compounds were identified and corroborated through various analyses, including melting point, IR, 1HNMR , 13CNMR , and MS. Also, density functional theory (DFT) calculations at the B3LYP/6–311++G(d,p) theoretical level were employed to study the chemical reactivity regarding local and global electrophilicity through the Fukui function reactivity index analysis. The results achieved by the DFT calculations are entirely consistent with the experimental data.