Degradation sulfonic acid chlorides

Reactions other than those of the nucleophilic reactivity of alkyl sulfates iavolve reactions with hydrocarbons, thermal degradation, sulfonation, halogenation of the alkyl groups, and reduction of the sulfate groups. Aromatic hydrocarbons, eg, benzene and naphthalene, react with alkyl sulfates when cataly2ed by aluminum chloride to give Fhedel-Crafts-type alkylation product mixtures (59). Isobutane is readily alkylated by a dipropyl sulfate mixture from the reaction of propylene ia propane with sulfuric acid (60). 

This technique, however, was less than satisfactory. The polymeric acid chlorides were very sensitive to hydrolysis and polymer degradation occurred, presumably due to the presence of HCl. This decomposition was reflected by a decrease in viscosity during this reaction sequence. Furthermore, the final polymers exhibited strong, broad hydroxyl stretching bands in their IR spectra. Transesterification was also attempted unsuccessfully. Poly(ethyl acrylate) was reacted with pentachlorophenol in the presence of p-toluene sulfonic acid in benzene. Very little ethanol was Isolated and upon precipitation of the polymer in petroleum ether only oily material remained. 

In this context our interest was focused on sulfonic acid esters of starch, derived fh)m the reaction of organic sulfonyl chloride (e.g. benzene, methane, or toluene sulfonyl chloride). These derivatives can be employed as partially protected and reactive intermediates. Up to now, especially the reaction of starch with p-toluenesulfonyl chloride in pyridine was studied, i.e. under heterogeneous reaction conditions, which may be accompanied by several side reactions. Alternatively, a homogeneous procedure was published using dimethyl sulfoxide as solvent for starch. However, the sulphur contents of the products were very low and an extensive degradation of the polymer occured . The extent of / toluenesulfonyIation of primary and secondary groups was determined by the iodination method. It was revealed that the reaction proceeds faster at 0-6 than at 0-2 and 0-2... 

During the sulfonation process, extensive gas (HCl, SO ) formation takes place The amounts of hydrogen chloride and sulfur dioxide gases, as well as the rate of their release, increase and the reaction time decreases when the amount of chlorosulfonic acid used in the reaction is increased incrementally During the sulfonation process using chlorosulfonic acid, other reactions such as dehydrochlorination, oxidation, quaternary degradation, and quaternary regrouping also take place. 

---