Ab initio calculations for the optical rotations of conformationally flexible molecules: a case study on six-, seven-, and eight-membered fluorinated cycloalkanol esters
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Updated: Aug 11, 2026

Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
Stefan Grimme1, Arnold Bahlmann, Günter Haufe
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Münster, Germany. grimmes@uni-muenster.de
Abstract:
Based on the time-dependent density functional response theory, an approach for the prediction of optical rotations of enantiomers of conformationally flexible molecules was developed. The method was applied successfully for the determination of the absolute configuration of trans-2-fluorocycloalkanol acetates with different ring sizes. The largest deviations between experimental and theoretical [alpha](D) values are 10 deg x [dm x (g/cc)](-1) (about 20% error). These theoretical results suggest that the optical rotation in these molecules is dominated by the local (1R;2R) configuration of the two substituents and that different ring and even axial/equatorial orientations play a less important role.
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