Homogeneous Metal-Based Catalysis in Supercritical Carbon Dioxide as Reaction Medium

Above 31.1 °C and 73.8 bar, carbon dioxide reaches the supercritical state, being transformed into a fluid ( sc CO 2 ) that has attracted interest in the last few decades as reaction medium for several transition-metal-catalyzed organic transformations. The main feature of this fluid rests on its capability to dissolve large amounts of other gases such as hydrogen, carbon monoxide, ethylene, or even methane and light alkanes. In this manner, very high concentrations of these reactants are available for catalysis. In this contribution a review of the main achievements of the use of transition-metal complexes as catalysts in sc CO 2 is presented.