Chlorosulfonic adds

Toluenesulfonyl Chloride. Toluene reacts with chlorosulfonic add to yield both o- and / -loluenesulfonyl chlorides, The ortho isomer is converted to saccharin, The para isomer is used for preparation of specialty chemicals. Annual toluene requirements are ca 6500 t (2 106 gal). 

Not affected by w, aqua regia, chlorosulfonic add, acetyl chloride, B fluoride, hot nitric acid, boiling solns of NaOH and organic solvents. 

The same authors " prepared copoly(vinyl alcohol-styrenesulfonic acid) resins which catalyze the hydrolysis of cubohydrates, among them dextrin and sucrose. Also, cation-exchanger membranes (from radiochemical grafting of styrene followed by reaction with chlorosulfonic add) were patented for the hydrolysis of dextrin to D-glucose. The results discussed may be useful for introducing subtle modifications into dextrins already prepared. A review on modified (converted) starches appeared in 1987. 

No other add is needed because chlorosulfonic add is a very strong acid indeed and proto-nates itself to give the electrophile. This explains why OH is the leaving group rather than Cl and why chlorosulfonation rather than sulfonation is the result. 

After the polymerization step the styrene-divinylbenzene copolymer is activated by sulfonation with chlorosulfonic add. The result is a polymer/carrier composite material that is a universal heterogeneous catalyst with the shape of a Rasdiig ring, well-suited for RD purposes. 

Sulfonation is the final step for the preparation of polystyrene-based membranes for fuel cell apphcations. In this reaction a sulfonic acid group is added to the aromatic ring by electrophihc substitution. Sulfonation can be performed by several agents such as sulfiu ic acid, sulfur trioxide, sulfonyl chloride, acetyl sulfate, and chlorosulfonic add. 

The reaction of toluene and excess chlorosulfonic add produces a mixture of tolu-ene-2- and toluene-4-sulfonyl chloride. At low temperatures (approx. 0 °C) the formation of the 2-isomer is favored, whereas at high temperatures a concentration of the 4-isomer of around 80% can be obtained. The isomers can be separated by distillation or by crystallization. 

The chlorosulfonic add process, applied to anhydrous HCl, is somewhat different, because water does not appear in the equation. The first step is the reaction of HCl with SO3 to form the acid ... 

Cameron, G. R. 1954. Toxicity of Chlorosulfonic Add-Sulfur Trioxide Mixture Smoke Clouds, Journal of Pathology and Bacteriology, vol. 68, pp. 197-204. 

The intermediate sulfonic acid is converted to its sulfonyl chloride derivative by reaction with a second equivalent of the chlorosulfonic add ... 

Second, because the sulfonyl group is introduced using chlorosulfonic add, an addic medium is present. Under these conditions, because free HQ is available (see discussion in Experiment [C2]), the amino group would be pro-tonated and become a meta directing group. This situation would lead to the formation of the wrong isomer or, at best, a mixture of isomers. 

Toxicology LD% (oral, rat) 9210 mg/kg mod. toxic by skin contacL IP route mildly toxic by ing. may cause headache, nausea, dizziness, drowsiness, and incoordination eye irritant experimental teratogen and reproductive effects TSCA listed Environmental VOC BODS 0.12 COD 1.71 ThOD 1.73 Precaution Flamm. exposed to heat or flame can react with oxidizers reacts violently with Ca(OCI)2 chlorosulfonic add oleum Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and irritating fumes... 

---