Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 8, 1985
Previous Article Next Article

Aromatic sulphonation. Part 94. Sulphonation and sulphation of the three 2- and 4-hydroxy- and 2- and 4-methoxy-benzenesulphonic acids in concentrated sulphuric acid

Abstract

The sulphonation of 2-methoxy-(1) and 4-methoxy-benzene sulphonate (2) and 1-(3), 3-(4), and 4-hydroxybenzenesulphonate (5) in 86.9–98.5% H2SO4 at 25 °C has been studied. Substrates (1)–(3) and (5) all yield the corresponding 2,4-disulphonic acid as the exclusive product, whereas (4) yields a mixture of 2-hydroxybenzene-1,4- and 4-hydroxybenzene-1,2-disulphonic acid. 3- and 4-Hydroxybenzenesulphonic acids in sulphuric acid (>87% H2SO4) are present in part as their hydrogen sulphates and the sulphuric acid concentration of 50% sulphation is 97.5 and 100.5 ± 0.2% H2SO4. The sulphonation is first order in the aromatic substrate. From the rate dependence on the sulphuric acid concentration it is concluded that the substrate species undergoing ring sulphonation is the O3SC6H4OR (R = H; Me) species with H2S2O7 as the sulphonating entity. From the observed proportionality between [O3SC6H4OSO3H]/[O3SC6H4OH] and aSO3 it is concluded that the aromatic species undergoing sulphation is again O3SC6H4OH.

Back to tab navigation

Article information


J. Chem. Soc., Perkin Trans. 2, 1985, 1241-1246
Article type
Paper

Aromatic sulphonation. Part 94. Sulphonation and sulphation of the three 2- and 4-hydroxy- and 2- and 4-methoxy-benzenesulphonic acids in concentrated sulphuric acid

A. Koeberg-Telder, H. J. A. Lambrechts and H. Cerfontain, J. Chem. Soc., Perkin Trans. 2, 1985, 1241
DOI: 10.1039/P29850001241

Search articles by author

Spotlight

Advertisements