Vibrational spectra and conformations of 2-(Bromomethyl)-2-methyl-1,3-dibromopropane

Abstract The IR and Raman spectra of the title compound were recorded as a liquid and as amorphous and crystalline solids at low temperatures. Additional IR spectra were obtained as a solid at high pressure, and IR spectra were recorded in an argon matrix at 14 K, using nozzle temperatures of 313 and 700 K. No indication of a plastic phase was detected neither in the low temperature nor in the high pressure solids. Among the the seven possible conformers, three with symmetries C s , C 1 and C 3 without 1,3 - parallel CBr bonds are sterically favourable. The spectra revealed that the C s and C 1 conformers were the two most stable rotamers. The enthalpy differences between them were determined to be ΔH 0 (C 1 − C s ) = 3.2 ± 0.4 kJ mol −1 from IR solution spectra as well as from matrix spectra, and ΔH 0 (C 1 − C s ) = 3 ± 0.3 kJ mol −1 was obtained from Raman spectra of the liquid. Indications suggesting a third conformer (C 3 ) were found in the spectra.