The microwave spectrum and molecular structure of 3,3-difluoro-1,2-epoxypropane and its complex with the argon atom

Abstract As a small, chiral molecule with a strong and simple microwave rotational spectrum, 3,3-difluoro-1,2-epoxypropane is a promising candidate as a chiral tag for conversion of enantiomeric analytes into spectroscopically distinct diastereomers via formation of a non-covalently bound complex. The Fourier transform microwave spectra of this species and its complex with the argon atom are obtained from 5.1 to 21.0 GHz, and their structures determined. Not surprisingly, these structures for both the monomer and the argon complex show strong similarities with those previously determined for 3,3,3-trifluoro-1,2-epoxypropane and 3,3,3-trifluoro-1,2-epoxypropane–argon, but are different from those of the analogous propylene oxide species. This suggests that fluoromethyl and methyl substitution affect the bonding in the epoxy moiety and intermolecular interactions in distinctly different ways.