Reaction with chlorosulfuric acid

SAFETY PROFILE Poison by ingestion, subcutaneous, intravenous, and intraperitoneal routes. Moderately toxic by intramuscular route. Can cause liver and kidney damage. The liquid phenol reacts violendy with KOH. Product of reaction with chlorosulfuric acid decomposes violendy at 24°C. When heated to decomposition it emits toxic fumes of NOx. See also NITRO COMPOUNDS OF AROMATIC HYDROCARBONS. 

Explosive reaction with chlorosulfuric acid, hydroiodic acid, magnesium perchlorate, chromyl chloride. Forms sensitive explosive mixtures with metal halogenates (e.g., chlorates, bromates, or iodates of barium, calcium, magnesium, potassium, sodium, zinc), ammonium nitrate, mercury(1) nitrate, silver nitrate, sodium nitrate, potassium permanganate. Violent reaction or ignition with alkalies + heat, fluorine, chlorine, liquid bromine, antimony pentachloride. Reacts with hot alkalies or hydroiodic acid to form... 

Preparation and Manufacture. Fluorosulfuric acid, first prepared by combining anhydrous HF and cooled, anhydrous SO in a platinum container (1), has also been prepared from ionic fluorides or fluorosulfates and sulfuric acid (20,48). The reaction of chlorosulfuric acid (qv) with ionic fluorides also gives fluorosulfuric acid (49). 

General Reaction Chemistry of Sulfonic Acids. Sulfonic acids may be used to produce sulfonic acid esters, which are derived from epoxides, olefins, alkynes, aHenes, and ketenes, as shown in Figure 1 (10). Sulfonic acids may be converted to sulfonamides via reaction with an amine in the presence of phosphoms oxychloride [10025-87-3] POCl (H)- Because sulfonic acids are generally not converted directiy to sulfonamides, the reaction most likely involves a sulfonyl chloride intermediate. Phosphoms pentachlotide [10026-13-8] and phosphoms pentabromide [7789-69-7] can be used to convert sulfonic acids to the corresponding sulfonyl haUdes (12,13). The conversion may also be accompHshed by continuous electrolysis of thiols or disulfides in the presence of aqueous HCl [7647-01-0] (14) or by direct sulfonation with chlorosulfuric acid. Sulfonyl fluorides are typically prepared by direct sulfonation with fluorosulfutic acid [7789-21-17, or by reaction of the sulfonic acid or sulfonate with fluorosulfutic acid. Halogenation of sulfonic acids, which avoids production of a sulfonyl haUde, can be achieved under oxidative halogenation conditions (15). 

Aromatic sulfonyl chlorides can be prepared directly, by treatment of aromatic rings with chlorosulfuric acid. ° Since sulfonic acids can also be prepared by the same reagent (11-7), it is likely that they are intermediates, being converted to the halides by excess chlorosulfuric acid. The reaction has also been effected with bromo-and fluorosulfuric acids. 

The reaction of various alkenes with chlorosulfuric acid in the presence of dioxane represents a versatile method for the preparation of /3-sultones <1999EJ091>. Yields were not reported as these reactions were conducted in CDC13 and followed by NMR. However, it was observed that the reactions all went to completion (Scheme 15). 

The same authors also report on the reaction of alkenes with chlorosulfuric acid in the absence of dioxane <1999EJ091 >. Thus, treatment of various alkenes at —40°C with chlorosulfuric acid results in the formation of, r-alkyl hydrogen sulfates (Scheme 16). From the results presented it appears that the rcr-alkyl hydrogen sulfates are transformed into a mixture of internal trans- and m-/3-sultones upon warming to 0 °C. Subsequent sulfonation of these alkenes by S03 then yields the corresponding /3-sultones. Again isolation yields were not reported but the reactions appear to proceed in a quantitative manner. The same paper also describes the use of acetyl sulfate and trifluoroacetyl sulfate for the preparation of /3-sultones, but mixtures appear to result. 

Scheme 5.2-49 The reaction of toluene with chlorosulfuric acid in ionic liquids and dichloromethane [113],...

Reaction with Occgacids and Salts. Hydrogen chloride reacts with sulfur trioxide yielding Hquid chlorosulfuric acid [7790-94-5] (qv). 

The reaction can also be carried out with oleum, distilling the chlorosulfuric acid as it forms. Reaction with oxidizing oxyacids such as HNO Hberates chlorine. Anhydrous sulfates of the heavy metals form addition compounds with HCl that can be released by heating the complex to elevated temperatures. The complex CuSO 2HC1 has been used for storage and transport of HCl (23). 

This method is also used with alcohols of the stmcture Cl(CH2) OH (114). HaloaLkyl chlorosulfates are likewise obtained from the reaction of halogenated alkanes with sulfur trioxide or from the chlorination of cycHc sulfites (115,116). Chlorosilanes form chlorosulfate esters when treated with sulfur trioxide or chlorosulfuric acid (117). Another approach to halosulfates is based on the addition of chlorosulfuric or fluorosulfuric acid to alkenes in nonpolar solvents (118). 

Strong dehydrating agents such as phosphorous pentoxide or sulfur trioxide convert chlorosulfuric acid to its anhydride, pyrosulfuryl chloride [7791-27-7] S20 Cl2. Analogous trisulfuryl compounds have been identified in mixtures with sulfur trioxide (3,19). When boiled in the presence of mercury salts or other catalysts, chlorosulfuric acid decomposes quantitatively to sulfuryl chloride and sulfuric acid. The reverse reaction has been claimed as a preparative method (20), but it appears to proceed only under special conditions. Noncatalytic decomposition at temperatures at and above the boiling point also generates sulfuryl chloride, chlorine, sulfur dioxide, and other compounds. 

Modem plants manufacture chlorosulfuric acid by direct union of equimolar quantities of sulfur trioxide and dry hydrogen chloride gas. The reaction takes place spontaneously with evolution of a large quantity of heat. Heat removal is necessary to maintain the temperature at 50—80°C and thus minimize unwanted side reactions. The sulfur trioxide may be in the form of 100% Hquid or gas, as obtained from boiling oleum, ie, fuming sulfuric acid, or may be present as a dilute gaseous mixture as obtained direcdy from a contact sulfuric acid plant (24). The hydrogen chloride gas can be in the form of 100% gas or in a diluted form. 

Fire Hazard. Although chlorosulfuric acid itself is not dammable, it may cause ignition by contact with combustible materials because of the heat of reaction. Open fires, open lights, and matches should not be used in or around tanks or containers where hydrogen gas may be collected because of the action of chlorosulfuric acid on metals. Water, carbon dioxide, and dry-chemical fire extinguishers should be kept readily available. 

The pine acid chloride reacts slowly with water, but if more than a few % of chlorosulfuric acid (a usual impurity) is present, the reaction is rapid and could become violent with large quantities. 

Chlorosulfuric acid (HSO3CI) reacts with aromatic hydrocarbons to give sulfonic acids, sulfonyl chlorides, and sulfones, with the relative yields depending on the reaction conditions. The reaction with benzene with an equimolar amount of... 

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