Non-linearity of the extended selectivity relationship in electrophilic substitution of annelated aromatic systems

Abstract

The examination of variable resonance effects in reactions involving electron-deficient transition states is discussed using the Extended Selectivity Treatment, for various electron-rich systems undergoing electrophilic substitution. Curvature of plots of log(partial rate factor) against ρ, implying a variable σ⁺ parameter is found only for those aromatic systems carrying a benzo-substituent.