Benzenesulfonic acid nitration

Benzene reacts slowly with sulfuric acid alone to give benzenesulfonic acid. The reaction starts with the protonation of one molecule of sulfuric acid by another and the loss of a molecule of water. This is very similar to the first steps in nitration. 

Remarks. Ferrous sulfate can be used advantageously instead of salt to precipitate the m-nitrobenzenesulfonic acid. The iron salt is very difficultly soluble in 20 per cent sulfuric acid and can be filtered off directly without further treatment. The reduction is carried out exactly as described above. If benzene is sulfonated with 100 per cent sulfuric acid, and then the benzenesulfonic acid is nitrated at 100°, there are formed, according to the work of Obermiller, besides the meta sulfonic acid, considerable quantities of the ortho and para isomers. The latter can be separated quite easily tluough the magnesium salts, and this affords a method for obtaining the valuable o-aminobenzenesulfonic acid. The preparation of orthanilic acid starting with o-m trochlorobenzene has also been described. ... 

Although sulfonation resembles nitration and halogenation in many respects, there are certain important differences. The two most noticeable of these differences are the reversibility of sulfonation processes and the striking sensitivity of orientation to changes in the reaction temperature. Amino derivatives offer a further complication in that considerable amounts of ortho and para derivatives are often obtained. Thus at low temperatures, aniline gives a mixture of 0, m, and p-amino-benzenesulfonic acid,48 whereas dimethylaniline gives an almost equal... 

The vapor-phase nitration of benzene with NO2 was investigated by Suzuki et al. using polyorganosiloxanes bearing sulfonic acid groups and silica-supported benzenesulfonic acid catalysts [31]. Phenylsulfonic polysiloxane was the most active among the polysiloxanes tested, its activity was not related to the concentration of acid sites as determined by a titration method, however. From the partial pressure dependence of the reaction rate it was concluded that the formation of NO as the active species was the rate-limiting step [32]. 

What product(s) would result from nitration of each of the following compounds a. propylbenzene d. benzenesulfonic acid... 

In Summary Nitration of benzene requires the generation of the nitronium ion, N02, which functions as the active electrophile. The nitronium ion is formed by the loss of water from protonated nitric acid. Sulfonation is achieved with fuming sulfuric acid, in which sulfur trioxide, SO3, is the electrophile. Sulfonation is reversed by hot aqueous acid. Benzenesulfonic acids are used in the preparation of detergents, dyes, compounds containing leaving groups, and sulfa drugs. 

Blasting expls were improved by incorporating a wetting agent, such as 2-naphthyloxy-acetlc acid laurylamide, 2-naphthylstearyl-amine, or Na benzenesulfonate. The wetting agent renders the water-sol components more readily wettable by the liq nitrate esters, which are also more effectively dispersed. 

Many methods have been used for the preparation of various acidopentammineeobalt(III) salts.1 In some instances these procedures are specific for the synthesis of a particular salt. The procedure suggested here involves the reaction of carbonatopentamminecobalt(III) nitrate with an acid or acid salt. The resulting reaction mixture may then be digested for a short time to yield the desired product, or the aquo complex is isolated and converted to the acido compound at an elevated temperature. This method appears to be completely general and has been used to synthesize complexes containing coordinated bromide, chloride, thiocyanate, sulfate, formate, and various substituted acetates, benzoates, and benzenesulfonates in addition to those described here. 

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