Toluene-w-sulphonate anion

The nitration of 2-phenylethanesulphonate anion (i) and toluene-w-sulphonate anion (ii) in aqueous nitric acid containing some added perchloric or sulphuric acid has been studied.When the medium was... 

The operation of the nitronium ion in these media was later proved conclusively.15a c The rates of nitration of 2-phenylethanesulphonate anion ([Aromatic] < c. 0-5 mol l-1), toluene-w-sulphonate anion, p-nitrophenol, Af-methyl-2,4-dinitroaniline and A -methyl-7V,2,4-trinitro-aniline in aqueous solutions of nitric acid depend on the first power of the concentration of the aromatic.156 The dependence on acidity of the rate of lsO-exchange between nitric acid and water was measured,150 and formal first-order rate constants for oxygen exchange were defined by dividing the rates of exchange by the concentration of water.156 Comparison of these constants with the corresponding results for the reactions of the aromatic compounds yielded the scale of relative reactivities shown in table 2.1. 

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