The CO and CC fundamental and overtone stretching bands and the electronic absorption bands of some αβ-unsaturated ketones

Abstract

The infrared spectra of a number of styryl ketones and of two acetylmethyl cyclo-alkenes which could exist in one or more conformations have been measured in the region of the CO and CC fundamental and first overtone bands. The conformations could be planar s- trans, planar s- cis or non-planar, and the relative populations are discussed. The electrical and mechanical anharmonicities have been assessed. The effects of five solvents on the fundamental bands have been determined. Infrared spectra in potassium bromide discs have been obtained for those solid compounds which show two carbonyl bands in solution spectra, in order to ascertain whether only one form is present in the solid state. The ultraviolet absorption spectra have also been recorded.