The hydrolysis of Brilliant Green and some derivatives. Part 2. The kinetics of the hydrolysis of 3- and 4-substituted derivatives of Brilliant Green
Abstract
Rate constants have been measured for the reactions of hydroxide ion with the following derivatives of Brilliant Green in aqueous solution: 3-X (X = Cl, OMe, CF3, Me, NO2, NMe2, or OH); 4-X (X = Cl, OMe, CF3, Me, NO2, or NMe2). The substituents affect the rate of hydrolysis to an extent linearly related to the appropriate Hammett substituent constant. Thermodynamic parameters ΔH‡ and ΔS‡ have been obtained for each dye and the reaction is shown to be under entropy control.