Synthesis Of Functional Ionic Liquids And Its Application In Selective Electrochemical Reaction

Electro-organic synthesis is a high selective green synthetic methodology using electrons as redoxes and controlling potentials.Ionic liquids play a dual role as both solvents and electrolytes because of its great advantages such as less volatile,non-flammable,high conductivity and wide electrochemical window.In this paper,the electro-oxidative activation of?C-H bond of 1-methoxy-4-propylbenzene?p-PrB?in strong acidic ionic liquids and the selective electrochemical dehalogenation of polyhalogenated aromatic compounds in the ionic liquid solution were studied.Firstly,the four kinds of ionic liquids?HmimHSO₄,PyHSO₄,[HSO₃-C₃H₆-mim]HSO₄,[HSO₃-C₃H₆-Py]HSO₄?were synthesized and detected by ¹HNMR.Their properties such as pH,electrochemical stability were also measured.The electrochemical oxidation behavior of p-PrB on graphite electrode in the ionic liquid aqueous solution were studied by cyclic voltammetry?CV?,chronoamperometry?CP?and constant potential electrolysis method.The results showed that the electrochemical oxidative process of p-PrB in ionic liquids aqueous solution is a four-electron irreversible process and controlled by diffusion step.The diffusion coefficient D is 5.8×10^-8cm²·s^-1.The products were detected by GC-MS,and the main product was p-methoxybenzene acetone.Electro-oxidation kinetics parameters of p-PrB were analyzed by using CP and CV in different ionic liquids.Constant potential electrolysis of p-PrB was performed in different ionic liquids with different pH.The results showed that the electro-oxidative products of p-PrB were greatly effected by th pH of the ionic liquid aqueous solutions.The electrochemical reductive dehalogenation of polyhalogenated aromatic compounds in the ionic liquid solutions were studie by CV,constant potential electrolysis.The influence of substrate concentrations,scan rates,and amount of H₂O on the reaction of electrochemical dechlorination was systematicly studied.The electrolysis products were analyzed by HPLC.