e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
Inorganica Chimica Acta
3, 5-Dimethylpyrazole promoted sulfonation of acetic anhydride by H 2 SO 4 to sulfoacetic acid and methanedisulfonic acid, and crystal structures of the complexes …
Sulfuric acid can sulfonate acetic anhydride (but not acetic acid) to sulfoacetic acid, and also to methanedisulfonic acid in the presence of 3, 5-dimethylpyrazole. Under the experimental conditions employed, sulfonation of 3, 5-dimethylpyrazole with concentrated sulfuric acid in acetic anhydride/acetic acid as solvent leads to a mixture of approximately 47mol% 3, 5- dimethylpyrazole-4-sulfonic acid, 34mol% sulfoacetic acid and 19mol% ...
[Liebig Justus Liebigs Annalen der Chemie, 1835 , vol. 13, p. 32 Full Text Show Details Wetherill Justus Liebigs Annalen der Chemie, 1848 , vol. 66, p. 117 Full Text Show Details Strecker Justus Liebigs Annalen der Chemie, 1856 , vol. 100, p. 199]