Partition equilibria of phenols between water and anionic micelles : Correlation with the Octanol/Water System

The partition equilibria of a series of thirty substituted phenols bearing different chemical groups between aqueous solutions and sodium dodecylsulfate micelles was investigated by using micellar high-performance liquid chromatography and by studying the variation of the acidity constant. The contribution of each substituent to the free energy of transfer from water to micelles was estimated. The group contribution approach is shown to be valid for polysubstituted compounds under well defined conditions. A comparison with partition coefficients obtained in classical two-phase system (1-octanol/water), frequently used as biochemical model systems, is discussed