Spectroscopic studies. Part II. Steric conformations of some αβ-unsaturated ketones

Abstract
The infrared and ultraviolet spectra of some fixed s-cis and s-transαβ-unsaturated ketones have been examined, and three main trends emerge as criteria to distinguish the two conformations. By use of these criteria some labile αβ-unsaturated ketones have been assigned conformations which are believed to predominate at room temperature, although for a number of the ketones the actual conformation is probably non-planar.