Abstract
The magnitude of the coupling constants between adjacent ring protons in several monosubstituted benzenes has been determined. The values for the interaction between protons ortho and meta to the substituents were in the range of 8.1–8.4 c.p.s. The interaction between protons in the meta and para positions varied from 7.27–7.8 c.p.s. Although the relative insensitivity of these coupling constants to the character of the substituent precludes any accurate assessment of the cause of this variation, the changes in coupling constants are thought to be mainly a reflection of changes in π-electron distribution.