Fristrup, Peter2; Lassen, Peter Rygaard3; Johannessen, Christian3; Tanner, David Ackland2; Norrby, Per-Ola2; Jalkanen, Karl J.5; Hemmingsen, Lars Bo Stegeager3
1 Organic Chemistry, Department of Chemistry, Technical University of Denmark2 Department of Chemistry, Technical University of Denmark3 Department of Physics, Technical University of Denmark4 Centre for Catalysis and Sustainable Chemistry, Department of Chemistry, Technical University of Denmark5 Department of Micro- and Nanotechnology, Technical University of Denmark
combined experimental and theoretical approach
Three possible methyl-substituted phenyloxiranes have been synthesized in enantioenriched form (89-99% enantiomeric excess (ee)), and their vibrational absorption (VA) and vibrational circular dichroism (VCD) spectra have been recorded. The experimental spectra are compared to theoretical spectra obtained from quantum mechanical calculations (density functional theory with the B3LYP hybrid exchange correlation functional with 6-31++G**, aug-cc-pVDZ, or aug-cc-pVTZ basis set) and related to the physical structure of the compounds. The absolute configuration could be established directly in each case by comparing experimental and theoretical spectra. In addition, we have been able to document the changes that occur both in structures and in the VA and VCD spectra due to substituent effects on the oxirane ring.
Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory, 2006, Vol 110, Issue 29, p. 9123-9129