A sustainable process for electrochemical production of 2-Iodosylbenzoic acid

Abstract

Herein, an environmentally friendly, scalable and highly efficient process for production of 2-iodosylbenzoic acid, a well-established hypervalent iodine oxidant is reported. It is based on anodic oxidation of 2-iodobenzoic acid in anhydrous AcONa-AcOH electrolyte followed by simple work-up of solid product. In particular, a benefit of the developed electrochemical process is absence of any chemical oxidant, application of environmentally benign solvent, high Faradaic efficiency and product yield. The process on the anode side combines anodic oxidation of reactant to the desired product with separation process, i.e. removal of Na+ cation from the anolyte through a cation-exchange membrane leading to drop of AcONa concentration. Consequently, the product of high purity can be obtained simply by filtering the anolyte solution followed by drying the filtration cake. Interestingly, no washing by organic solvents is required. Moreover, both anolyte filtrate and catholyte can be reused multiple times. Energy and material balance and cost and environmental footprint analysis showed benefits of the developed process and suggested clear strategy towards further reduction of the product cost and, in particular, significant decrease of a generated waste amount.