INVESTIGATION OF THE INFRARED ABSORPTION SPECTRA OF SELECTED AROMATIC COMPOUNDS

As the first step in making assignments of the low-frequency vibrations of para-substituted benzene compounds, complete vibrational assignments of several representative compounds have been started. While assignments have been made for many monosubstituted benzenes, there is need forA COMPLETE ASSIGNMENT OF A MONOSUBSTITUTED BENZENE WITH AN ELECTRON-ATTRACTING SUBSTITUENT. To fill this need, an assignment of benzonitrile has been made. Attempts to prepare benzonitrile-d sub 5 were unsuccessful, but are being continued. To confirm the previous assignment of phenol, a sample of phenol-2,4,6-d sub 3 was prepared. A complete vibrational assignment of this molecule was made. Attempts to prepare phenol-d sub 5 are in progress. The assignments of p-cresol and deuterated p-cresols was carried almost to completion. Using the vibrational assignments mentioned above as a foundation, the low-frequency vibrations of 28 para-substituted benzene compounds were assigned as completely as possible. It was shown that certain of the lowfrequency vibrations are sensitive to the nature of the substituent. Author