Infrared intensities as a quantitative measure of intramolecular interactions. Part XLIII. Quantitative estimation of electronic interactions in mono- and di-substituted ethylenes and the prediction of rotational barriers

Abstract

Known rotational barriers in monosubstituted ethylenes are discussed in terms of substituent resonance and strain parameters. Related reasoning allows the rationalisation of known rotational barriers in 4-(dimethylamino)but-3-en-2-one in terms of substituent-ethylene and substituent–substituent interactions.