Abstract
The carbonyl stretching frequency, vC=O, decreases as the polarity of the solvent increases. The vC=O frequencies for dialkyl ketones are affected by intermolecular hydrogen bonding of the solvent proton with the free pair of electrons on the carbonyl oxygen atom. The strength of the intermolecular hydrogen bond is determined by steric effects of both the solvent and solute, the acidity of the intermolecular hydrogen bond proton, and the basicity of the ketone carbonyl group.