Correlation of the Rates of Solvolyses of Carbomethoxybenzyl Bromides Using the Grunwald-Winstein Equation

摘要

Some years ago,Andrews and co-workers studied the effects of ortho-substitution on nucleophilic substitution reactions of benzylic derivatives in 80% aqueous dioxane.They proposed that ortho-groups possessing a nucleophilic center could give intramolecular assistance to reactions;the relatively high reactivity of the ortho isomer has been explained on the assumption that its carboxylic acid group can participate electronically in the activation process by releasing electrons to the vacant p-orbital developing at the reaction center.Although previous workers have carried out some product studies showing intramolecular participation,they show only a profile of the products after completion of reaction.