LINEAR SOLVATION ENERGY RELATIONSHIPS .6. ADDITIONS TO AND CORRELATIONS WITH THE PI-STAR SCALE OF SOLVENT POLARITIES

The solvatochromic comparison method is used with nine solvatochromic indicators to determine π* values for 23 additional solvents. The expanded π* scale of solvent polarity-polarizabilities is then used to rationalize solvent effects on rates of a Menschutkin reaction, rates of a peroxyester thermal decomposition, and free energies of transfer of a tetraalkylammonium halide between solvents. It is suggested that the excellent correlations serve as ultimate vindication of the underlying concept of linear solvation energy relationships, i.e., that when polarity, polarizability, and hydrogen bonding effects are correctly unravelled, solvents exert parallel effects on many chemical properties and reactivity parameters. © 1979, American Chemical Society. All rights reserved.