Chlorosulfonic acid solvent

Extensive literature demonstrated that chlorosulfonic acid is an effective reagent for the conversion of phenols into phenolpolysulfonyl chlorides. The reagent caused four different types of reaction sulfonation, chlorosulfonation, chlorination and oxidation. In some instances, the phenolic hydroxyl group was esterified (sulfated) prior to sulfonation and in other cases condensation products, e.g. sulfonylides, were isolated. The predominance of any of the quoted reaction types depends on the experimental conditions, e.g. time, temperature, quantity of chlorosulfonic acid, solvent (if any) and the nature of the phenolic substrate. 

Carbohydrates. Carbohydrates (240—244) of any form are easily sulfated in the presence of solvent, using sulfating reagents such as SO —pyridine, SO —triethjlamine, SO.—trimethyl amine, or chlorosulfonic acid—pyridine. As an example, starch (qv) is sulfated using SO.—trimethyl amine at 0 to 5°C in aqueous media (16). Sulfated carbohydrate products find some use in industry as thickening agents. 

The chemical resistance of PTFE is almost universal It resists attack by aqua regia, hot fummg nitnc acid, hot caustic, chlorine, chlorosulfonic acid, and all solvents. Despite this broad chemical resistance, PTFE is attacked by molten alkali metals, ammonia solutions of such metals, chlorine trifluoride, and gaseous fluonne at elevated temperature and pressure PTFE swells or dissolves m certam highly fluonnated oils near its melting point. Specific lists of chemicals compatible with PTFE are available [/.8]... 

Not affected by w, aqua regia, chlorosulfonic acid, acetyl chloride, B fluoride, hot nitric acid, boiling solns of NaOH and organic solvents-Not wetted by w. No substance has been found which will dissolve the polymer, but prolonged contact with fluorine, hot plasticizers and polymeric waxes is not recommended (Refs 1 6)... 

Materials. The starting PPO was purchased from Aldrich Chemical Co. Two reprecipitations from chloroform into methanol served to purify the polymer. The bromine, chlorosulfonic acid, sulfonyl chlorides, acid chlorides as well as all other reagents and solvents were purchased from Aldrich Chemical Co. and were used without further purification. 

Oxidation may be achieved in the presence of oxygen or air. Other suitable oxidants include sulfur, sodium polysulfide, iron (III) chloride, potassium ferro-cyanide (III) or potassium dichromate, peroxydisulfate or salts of aromatic nitro-sulfonic acids. An aqueous/alkaline medium is used in the presence of a high boiling organic solvent which is not miscible with water or which is almost immiscible with water. Cyclization with chlorosulfonic acid can be followed directly by oxidation with bromine to afford the thioindigo system, without separation of the intermediate. 

Pyranthrone may be halogenated, for instance, in chlorosulfonic acid in the presence of small amounts of sulfur, iodine, or antimony as a catalyst. This procedure necessitates intermediate separation and purification of pyranthrone after manufacture, because the products, unless purified, fail to furnish the solvent fastness which is characteristic of a typical pigment. 

Bromination of 6,14-dichloropyranthrone in chlorosulfonic acid in the presence of a catalyst provides 0.1 to 2.2 bromine atoms per molecule, depending on the reaction conditions. The exact outcome is controlled not only by the choice of solvent but also by the type of catalyst and the amount of bromine, as well as by the reaction time and reaction temperature. 

The unsulfonated random copolymers are reportedly synthesized at 50 °C over a period of 48 h using emulsion polymerization with dodecylamine hydrochloride surfactant in water as the reaction system and potassium persulfate as the initiator. The copolymer is then dissolved in an appropriate solvent such as dichloroethane or chloroform and sulfonated using reagents such as chlorosulfonic acid or a sulfur trioxide complex. It has been reported that this generation of BAM membranes exhibited some su-... 

Solutions of poly(l,4-phenylene-2,6-benzobisthiazole), PBT, exhibit an isotropic to nematic phase transition in a variety of solvents including methane sulfonic acid, MSA, chlorosulfonic acid, CSA, and poly phosphoric acid, PPA (1-4). In the latter case the transition occurs over a range of water -P2O5 compositions. In these acids the polymer, with repeating unit... 

The benzobisazole family of rigid-rod polymers is soluble in acidic solvents such as PPA, methanesulfonic acid, chlorosulfonic acid, 100% sulfuric acid and Lewis acid salts such as antimony trichloride and bismuth trichloride. More recently, PBZT has been reported [22] to form liquid crystalline solutions in nitromethane containing aluminum trichloride or gallium trichloride. Since the glass transition temperature of these materials is above their decomposition temperature, they must be processed from solution. 

SYNTHESIS To 26.4 g veratrol that was being magnetically stirred without any solvent, there was added 50 g chlorosulfonic acid a bit at a time over the course of 20 min. The reaction was exothermic, and evolved considerable HCI. The deeply colored mixture that resulted was poured over400 mL crushed ice and when all had thawed, it was extracted with 2x150 mL CH2CI2. 

The unavoidable excess of sulfuric acid in sulfonation reactions using sulfuric acid or oleum causes, under some conditions, such undesirable side reactions as further sulfonation or rearrangement of the sulfonic acid formed initially. These difficulties can be avoided by effecting the sulfonation with the calculated quantity of chlorosulfonic acid in an organic solvent which is not attacked by this reagent (usually nitrobenzene). For further details on this method, see the preparation of 2-naphthol-l-suIfonic acid, page 199. 

If sulfonation is done with a large excess of chlorosulfonic acid without a solvent, the sulfochloride is formed, as a rule, instead of the free sulfonic acid. For example, large quantities of the mixture of o- and p-toluenesulfoi l chlorides are prepared in this way ... 

Dodecylbenzenesulfonyl chlorides have been prepared from the corresponding acids using chlorosulfonic acid,4 phosphorus oxychloride,2 and thionyl chloride.5 The use of catalytic amounts of DMF in conjunction with thionyl chloride is based on the work of H. Bosshard, et al. The insolubility of the DMF/thionyl chloride complex in the reaction solvent permits easy removal at the end of reaction. Extraction with dilute base removes the last trace of acids and the solution is pure enough for the next step. 

As pointed out earlier, fluorocarbon elastomers are highly resistant to hydrocarbons, chlorinated solvents, and mineral acids. Vulcanizates from them swell excessively in ketones and in some esters and ethers. They also are attacked by amines, alkali, and some acids, such as hot anhydrous hydrofluoric acid and chlorosulfonic acid [9]. Generally, stability and solvent resistance increase with increasing fluorine contents, as shown in Table 5.3. 

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