Investigation of the effect of the solvent medium on the conformational behavior of phenylethylamines by empirical method.
The effect of dielectric constant (solvent medium) on the conformational behavior of six phenylethylamines has been investigated using the empirical method. Various physical properties, such as rotamer population, dipolemoment, optical anisotropy, and depolarization ratios are examined. The effective intramolecular dielectric constant has been varied from 1.0 (vacuum) to 80.0 (highly polar medium). It is shown that all these properties truly depend on the magnitude of the dielectric constant (nature of the solvent medium), but the effect is more pronounced when the dielectric constant is less than about 30.0. In addition, the effect of various groups has been assessed by using the above-mentioned properties. In general, allthe six compounds studied here possess three energy minima corresponding to one trans and two gauche forms. These energy minima have shifted only once when the dielectric constant is increased from 1.0 to 5.0. Thus, it is concluded that the nature of the solvent medium is critical in assessing percent population, ionic character, and polarizability of the molecule but not in describing the energy minima.
D004563:Electrochemistry; D008433:Mathematics; D008968:Molecular Conformation; D010627:Phenethylamines; D012997:Solvents / Q000494:pharmacology*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013816:Thermodynamics
D010627:Phenethylamines; D012997:Solvents