The Mn(Salen)Cl and Ni(Salen)-catalyzed oxidation of limonene has been carried out. The catalytic cycle involved PhIO via a rebound mechanism. In all cases the use of organic solvents resulted in reasonable selectivities of oxidized products. The use of supercritical. carbon dioxide (SCCO2) led at least to comparable results in terms of conversions, but showed different selectivities. In ordinary solvents epoxidation appears to predominate over allylic oxidation. This tendency, in SCCO2, appears only after 4 h of reaction. Shorter reaction times (2 h) appear to lead to opposite selectivity. These results showed the advantages of using SCCO2 as solvent in these reactions. SCCO2 is much more compatible with green technology than are organic solvents.