Importance of intramolecular dipolar interactions in determining the configurations of polysubstituted succinonitriles in solution

Abstract

The dipole moment of racemic(±)-2,3-dicyano-2,3-diphenylbutane is lower than that of its meso-isomer, unlike the values for the corresponding stilbene dichloride diastereoisomers: this fact, together with evidence adduced from related molecules, shows that intramolecular dipolar interactions can have overriding importance in determining the conformation and relative abundance of rotational isomers of diastereoisomers in solution.