A modification of the Dewar-Grisdale equation, parameterized with Brown's electrophilic substituent con-stants, g+, and CNDO/2 regional charge distributions, is successful in correlating reactivity ratios for the solvolysis of a wide variety of heteroarylethanol derivatives and nuclear substituted analogues. The equation log kMMe/kH= 1.4 lpAqjj, predicted by this development, is closely obeyed by the observed reactivity ratios for 34 pairs of ...