Chapter 2: Carboxylation with CO₂

Carbon dioxide (CO₂) is an ideal source of carbon because it is inexpensive, non-toxic, and abundant. In general, the development of carbon–carbon bond forming reactions is not easy because CO₂ is thermodynamically and kinetically stable. However, recent progress in the strategies used for CO₂ fixation utilizing transition metals is very useful for catalytic carboxylation toward the synthesis of carboxylic acid derivatives. In this chapter, the recent progress in the transition-metal-catalyzed carboxylation of CO₂ is reviewed, including the carboxylation of unsaturated hydrocarbons, organometallic reagents, and organic halides, as well as carboxylation via carbon–hydrogen bond activation.