Electron interactions and infrared spectra of para isomers of X(CF3Y)C6H4 compounds

IR spectra are reported for, in which X represents various polar substituents and Y a bridge with multiple bonds. There is a linear relation between the frequency of the v^E_C-F(H) degenerate vibration and Taft's induction constant * for the radical attached to the CF₃ group. Frequency v^E_C-F is also correlated with the _n, which shows that the conjugated system can transmit the electron effect of X to the CF₃ group. Compounds are compared as regards this transmission, and some features of the frequencies of the multiple bonds are elucidated.See[6, 7] for brief details of the spectra of some of the compounds.