Collect. Czech. Chem. Commun. 1984, 49, 1182-1192

Dissociation of substituted benzenesulphonamides in water, methanol and ethanol

Miroslav Ludwig, Oldřich Pytela, Karel Kalfus and Miroslav Večeřa

Department of Organic Chemistry, Institute of Chemical Technology, 532 10 Pardubice


Thirteen monosubstituted arylsulphonamides (XC6H4SO2NH2) and two 3,4-disubstituted arylsulphonamides (X2C6H3SO2NH2) have been synthetized and their dissociation constants have been measured by potentiometric titration in water, methanol, and ethanol. The Hammett substitution dependences have been calculated for all the media, and changes in the reaction constants due to transition from water to alcohols are discussed in confrontation with analogous dependences of benzoic acids. The reaction constant ρ found in methanol is lower than that in water. The dissociation constants have been treated mathematically by the method of the principal components and by multiple linear regression.