Sulfonation, with chlorosulfonic acid

Reaction with cold nitric acid results primarily ia the formation of 5-nitrosahcyhc acid [96-97-9]. However, reaction with fuming nitric acid results ia decarboxylation as well as the formation of 2,4,6-trinitrophenol [88-89-1] (picric acid). Sulfonation with chlorosulfonic acid at 160°C yields 5-sulfosahcyhc acid [56507-30-3]. At higher temperatures (180°C) and with an excess of chlorosulfonic acid, 3,5-disulfosahcyhc acid forms. Sulfonation with hquid sulfur trioxide ia tetrachloroethylene leads to a nearly quantitative yield of 5-sulfosahcylc acid (1). 

Sulfonation with chlorosulfonic acid requires special corrosion-proof equipment either glass-lined steel or all glass. The latter is especially suitable for small batch size sulfonation. The HC1 absorber also is built of either glass-lined steel or all glass. 

Mulhaupt et al. synthesized novel soluble copoly-arylenes via a Ni(0)-catalyzed coupling reaction of aryl chlorides. Molar ratios of dichlorodiphenyl sulfone (a) to m-dichlorobenzene (y) were used to vary the amount of m-phenylene in the final copolymer. Then these copolymers were dissolved in chloroform and sulfonated with chlorosulfonic acid. The synthe-... 

Succinaldeliyde, 7, 41 Succinic acid, 5,10 Succinic ester (ethyl), 5, 10 Sulfonation, with chlorosulfonic acid,... 

Hydroxypyridines undergo a variety of other electrophilic substitution reactions. Sulfonation of 2-pyridone with 10% oleum at 180° gave the 5-sulfonic acid.69 110 A-Methyl-2-pyridone is similarly sulfonated with chlorosulfonic acid. The action of fuming sulfuric acid gave a mixture of the 5-sulfonic acid and the 3,5-disulfonie acid. A nitro group at C-5 is said not to hinder the reaction, sulfonation at the... 

The toluene-para-sulfonate group (OTs) is important as a leaving group if you want to carry out an S>j2 reaction on an alcohol (Chapter 17) and the acid chloride (tosyl chloride, TsCl) can be made from the acid in the usual way with PC15. It can also be made directly from toluene by sulfonation with chlorosulfonic acid CISO2OH. This reaction favours the ortho sulfonyl chloride which is isolated by distillation. 

In the laboratory of R. Bihovsky, a series of peptide mimetic aldehyde inhibitors of calpain I was prepared in which the P2 and P3 amino acids were replaced with substituted 3,4-dihydro-1,2-benzothiazine-3-carboxylate-1,1-dioxides. The synthesis began with the diazotization of the substituted aniline substrate using sodium nitrite and hydrochloric acid. The aqueous solution of the corresponding diazonium chloride product was added dropwise to the solution of acrylonitrile in a water-acetone mixture, which contained catalytic amounts of copper(ll) chloride. This Meerwein arylation step afforded the chloronitrile derivative, which was subjected to sulfonation with chlorosulfonic acid, and the resulting sulfonyl chloride was treated with the solution of ammonia in dioxane to give the desired 3,4-dihydro-1,2-benzothiazine-2-carboxamide. 

It has been reported that sulfonation with chlorosulfonic acid at 33-45°C gives a product free from meto-cresol. 

The reaction of fluorosulfonic acid is probably similar but has not been investigated so extensively. The action of chlorosulfonic anhydride leads to such a complex mixture of products that this reagent is of little value. Sulfonation with chlorosulfonic acid is often carried out in an inert solvent, - usually chloroform. 

These aromatic polymers are easily sulfonated by concentrated sulfuric acid [12], by chlorosulfonic acid [13], and by pure or complexed sulfur trioxide [14]. Sulfonation with chlorosulfonic acid or fuming sulfuric acid sometimes causes chemical degradation in these polymers. According to Bishop et al. [15], the sulfonation rate of PEEK in sulfuric acid can be controlled by changing the reaction time and the acid concentration and can thereby provide a sulfonation range of 30-100% without chemical degradation or cross-linking reactions [16]. However, this direct sulfuric acid procedure cannot be used to produce truly random copolymers at sulfonation levels of less than 30%, because dissolution and sulfonation in... 

Nitroacenaphthene 112 reacts with excess chlorosulfonic acid to yield the 7-sulfonyl chloride 113 (Equation 36). Acenaphthalene normally sulfonates with chlorosulfonic acid in the 5-position (see Section 2, p 45) so it is perhaps surprising that sulfonation of the 5-nitro derivative 112 did not occur in the equivalent 6-position. However, this would be hindered by peri interaction with the bulky 5-nitro group, so the SO3H group migrates to the less hindered 7-position. 

An improved procedure for the chlorosulfonation of substituted diaryl sulfones involves heating the appropriate 4,4 -dialkyl or dihalodiaryl sulfone with chlorosulfonic acid (2-4 equivalents) at 140-150 °C and subsequent treatment with thionyl chloride (6-10 equivalents). The action of chlorosulfonic acid on propiophenone (ethyl phenyl ketone 226) results in a novel cyclization reaction yielding 3-chloro-2-methylbenzothiophene-1,1-dioxide 227 (Scheme 2). The reagent similarly caused smooth cyclization of Mannich bases 228, the reaction again proceeding via the enolic sulfonic acid to yield the cyclic sulfone 229 (Equation 72). ... 

The yield of the sulfonylide 106 increased with the amount of chlorosulfonic acid used and with a large excess of the reagent (10 equivalents), it was almost the only reaction product. 7-Methoxy-4-methyl-8-acetylcoumarin could not be sulfonated with chlorosulfonic acid (one or two equivalents) at 60 °C, while at higher temperatures, sulfonation occurred with some demethylation. Compounds analogous to the sulfonylide 106 are known to be formed in the sulfonation of substituted phenols (see Chapter 4, p 62). 

Poly(vinyl fluoride) films have also been sulfonated with chlorosulfonic acid and the state of water in the sulfonated polymer membranes was examined by FTIR spectroscopy. The results showed that the water contained hydrogen and non-hydrogen bonded molecules containing a large number of proton complexes, e.g. H3O+ or H5O2+. ... 

Chlorosulfonyl styrene-divinylbenzene copolymer is a highly reactive intermediate used in organic synthesis. The aromatic styrene groups of the copolymer are sulfonated with chlorosulfonic acid in dichloroethane, followed by chlorination of the sulfonate groups with phosphorus pentachloride-phosphorus oxychloride mixture. ... 

Greiner et al. [152] prepared fluorinated ether sulfates, H-(CF2CF2) CH2 [0CH2CH2], 0S03NH4, n = 2, 3, 4, m = average 3. The telomer alcohols were oxyethylated using BF3 as the catalyst, sulfonated with chlorosulfonic acid, and neutralized with ammonia. 

PPO is readily sulfonated with chlorosulfonic acid. (Scheme 5) The sulfonated polymer 13 was tested as an antistatic material and has... 

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