Application of the additivity of shielding effects in olefinic compounds for configurational assignments to isomeric 4-amino-1,2-diarylbut-2-enes possessing antihistaminic activity

Abstract

The configurations of the isomeric hydrohalides of 4-dimethylamino-1,2-diphenylbut-2-ene are deduced by use of the additivity principle for shielding effects in olefinic compounds. Assignments agree with previous conclusions based upon qualitative consideration of the various screening influences of the double-bond substituents.

The principle is also applied to a pair of t-butylaminoalkenes but configurational assignments cannot be made owing to the significant steric interactions produced by the t-butyl grouping in these compounds.