Perfluorinated Solvents as Nonpolar Test Systems for Generalized Models of Solvatochromic Measures of Solvent Strength

The π* values of perfluorodlmethyldecalln, perfluorotrlbutylamlne, perfluoroheptane, and perfluorooctane have been found to be -0,33, -0.36, -0.39, and -0.41, respectively. These values Indicate that solvent polarizability provides a major contribution to the π* scale of solvent dlpolarlty/polarizability. A three-parameter equation Is shown to provide reasonable correlation for 76 solvents of solvent π* values for a variety of solvent types Including polychlorinated and aromatic solvents which are conventionally excluded from the so-called select solvent set. The utility of perfluorinated solvents as liquid-liquid extraction reference phase Is assessed and shown to be strongly dependent upon the Indicator solute being studied.