Electrochemical Fixation of Carbon Dioxide

Abstract

Electrochemical fixation of carbon dioxide in organic compounds with C–C bond formation yielding carboxylic acids is focused and reviewed in this chapter. Electrolysis of organic compounds in the presence of carbon dioxide results in efficient fixation of carbon dioxide in organic compounds with C–C bond formation to yield the corresponding carboxylic acids. When electrolysis is carried out in one-compartment electrochemical cell (undivided cell) using magnesium or aluminum as an anode material, efficient carboxylation can be achieved to give carboxylic acids in high yields. Electrochemical carboxylation is sometimes carried out in the presence of transition-metal catalyst, such as nickel, palladium, and their complexes, or electron transfer mediator, the use of which often results in drastic enhancement and control of chemo- and regioselectivity and efficiency of carbon dioxide fixation. Various organic compounds can be electrochemically carboxylated to give useful carboxylic acids. Some of them cannot be synthesized by conventional chemical fixation of carbon dioxide. One notable synthetic application of electrochemical fixation of carbon dioxide is synthesis of 2-arylpropanoic acids, nonsteroidal anti-inflammatory drugs (NSAIDs), and their useful precursors and derivatives. Electrochemical fixation of carbon dioxide also takes place by using supercritical carbon dioxide (scCO2), which can be realized under relatively moderate conditions (Tc = 31 °C, Pc = 7.5 MPa). By using acetonitrile as a cosolvent, efficient electrochemical fixation in scCO2 in organic compounds can be achieved and carboxylic acids including NSAIDs and their precursors can be obtained in high yields. In this chapter, these results are widely introduced with several representative examples.