The biphasic conjugation of soybean and other natural oils, as well as the isomerization of various alkenes, was examined using a rhodium catalyst. A maximum yield, of conjugated soybean oil, of 96% was obtained when the reaction was run at 80 °C under argon with ethanol as the polar solvent, using triphenylphosphine monosulfonate sodium salt (tppms) as the ligand, and the surfactant sodium dodecyl sulfate (SDS). The optimized conditions were tested with other substrates, and the products were analyzed by 1H NMR, GC/MS, and ICP-MS.