Desulfonation reaction
In organic chemistry, the desulfonation reaction is the hydrolysis of sulfonic acids:[1]
- RC6H4SO3H + H2O → RC6H5 + H2SO4
The reaction applied to aryl and naphthylsulfonic acids. It is the reverse of
sulfonation.[2]
The temperature of desulfonation correlates with the ease of the sulfonation.
Applications in synthesis
This reactivity is exploited in the regiospecific preparation of many di- and tri-substituted aromatic compounds. The approach exploits the meta-directing effect of the sulfonic acid group.
p-toluenesulfonic acid, followed by hydrolysis. The method is also useful for the preparation of 2,6-dinitroaniline[3] and 2-bromophenol via phenol-2,4-disulfonic acid.[4]