The spectra and structure of sulphur-containing organic compounds-V. The vibrational spectra and conformations of p-RC6H4SO2CH2X sulphones

The i.r. and Raman spectra of p-RC6H4SO2CH2X (R = H, CH3, Cl, Br; X = Cl, Br) sulphone liquid solutions and crystals have been investigated. The existence of a mixture of trans and gauche conformations in liquid and solution phases has been established. The temperature dependences of the i.r. spectra have been studied and the values of ΔH = H (gauche) - H(trans) determined. The molecular conformations in the crystal have been determined by the dichroism of polarized i.r. spectral bands. In the case of CH3C6H4SO2CH2Br polymorphic crystal modifications, differing in molecular conformations, have been found. An interpretation of the vibrational spectra is given. See Part IV, A. B. REMizov, F. S. BILALOV and 1. S. POMINOV, Spectrochim Acta, in press. © 1987