In continuation of our studies on the application of solid acids we found that silica gel reacts with chlorosulfonic acid to give silica sulfuric acid (I). It is interesting to note that the reaction is easy, clean and without any needed work-up procedure because HCl gas is evolved from the reaction vessel immediately. We also found that silica sulfuric acid (I) is an excellent candidate for sulfuric acid replacement in organic reactions without any limitations such as ...
