Electric dipole moments and conformations of 1,2-dipyridylethanes as solutes

Abstract

The electric dipole moments of seven 1,2-dipyridylethanes are reported and discussed in terms of the rotational isomerism arising from restricted intramolecular rotation within these molecules. The dielectric results enable certain diastereoisomers to be identified and steric effects on gauche–trans populations and the internal energy difference between them to be evaluated quantitatively.