Integrated intensities of hydroxy stretching vibration bands in some bicyclic systems containing a hydroxy group β to o-benzeno, etheno, epoxy, or epithio functions
Abstract
For the title class of compounds, OH stretching vibration bands, νOH, and integrated, intensities, AOH, were measured for dilute carbon tetrachloride solutions. When AOH values were compared for f-structures which are incapable of intramolecular hydrogen bonding and b-structures in which intramolecular bonding takes place, the result was remarkable in that the AOH values of free νOH bands in f-structures were greater than those for the hydrogen-bonded νOH bands in the b-structures. The CO and C–O stretching vibration bands, νCO and νC–O, for the corresponding acetates were also measured. The νCO bands for the f-structures shifted to higher wavenumbers than those for b-structures, but the νC–O bands are shifted to lower wavenumbers. These results were ascribed to the through-space interaction between π- or n-electrons and the sp3-hybridized carbon atom bearing hydroxy and acetoxy groups which affects on polarization of these groups.