Using Dipoles to Control the Directionality of Functional Groups: Syn‐ and Anti‐Oriented Benzene‐1,3‐dicarboxamides

Poles apart: The relative orientation of a pair of functional groups—amides in this case—can be controlled by the choice of the substituent that lies between them. Groups which are effectively cylindrically symmetrical (Me, Cl) allow direct interaction between the dipoles of the amides and induce an anti orientation, whereas polar groups (OCOR, OSO2R, SO2R) interact with the dipole of both amides to yield a syn orientation (see picture).