title: Solvent effects on the optical rotation of (S)-(-)-alpha-methylbenzylamine.
abstract: The optical rotation of (S)-(-)-alpha-methylbenzylamine at 589 nm has been measured in 39 different solvents at five different concentrations: 0.25, 0.50, 1.00, 2.00, and 3.00 M. A correlation of the intrinsic rotations (i.e., extrapolation of specific rotations to zero concentration) with Kamlet's and Taft's solvent parameters (alpha, beta, and pi) is established. The polarity/polarizability, pi, and solvent acidity, alpha, terms are found to have a greater effect upon the optical rotation than the basicity of the solvent, beta. The specific rotation for (S)-(-)-alpha-methylbenzylamine has been calculated with Gaussian03 using a PCM model (B3LYP aug-cc-pVDZ) for all 39 solvated systems. Comparisons between the experimental and calculated values show the importance of hydrogen bonding on specific rotation.
authors.affiliation: Department of Chemistry, University of Tennessee, Knoxville, 37996, USA. afischer@utk.edu
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Fischer
authors.forename: Robert N
authors.initials: RN
authors.lastname: Compton
authors.forename: Richard M
authors.initials: RM
authors.lastname: Pagni