Decomposition of sulfuryl chloride

The decomposition of sulfuryl chloride is accelerated by light and catalyzed by aluminum chloride and charcoal. Many of the reactions of sulfuryl chloride are explainable on the basis of its dissociation products. Sulfuryl chloride reacts with sulfur at 200°C or at ambient temperature in the presence of aluminum chloride producing sulfur monochloride. It hberates bromine or iodine from bromides or iodides. Sulfuryl chloride does not mix readily with water and hydrolyzes rather slowly. 

The decomposition of sulfuryl chloride, SO U, to sulfur dioxide and chlorine gases is a first-order reaction. 

Sulfuryl chloride (also known as chlorosulfuric acid and thionyl chloride), SO2CI2, is used in a variety of applications, including the synthesis of pharmaceuticals, rubber-based plastics, dyestuff, and rayon. At a certain temperature, the rate of decomposition of sulfuryl chloride was studied. 

The gas-phase decomposition of sulfuryl chloride, S02C12 — S02 + Cl2, is thought to follow a first order rate law. The reaction is performed in a constant volume, isothermal batch reactor, and the concentration of S02C12 is measured at several reaction times, with the following results. 

Using Equation 3-314 for the gas-phase decomposition of sulfuryl chloride, it can represented by... 

The chlorination of methane can be carried out by bubbling the hydrocarbon gas through sulfuryl chloride (bp, 69°C) at a predetermined temperature. The higher the temperature, the larger the ratio of sulfuryl chloride vapor to hydrocarbon. The mixture of gases is passed through a tube filled with inert material and maintained at about 350°C. The flow is sufficiently rapid to constitute turbulent flow. It is necessary to use only a small quantity of catalyst, e,g., carbon otherwise, the decomposition of sulfuryl chloride will be too rapid, and the rate of formation of chlorine will then be greater than the reaction between chlorine and methane. 

As described in Exercise 14.41, the decomposition of sulfuryl chloride (SO2CI2) is a first-order process. The rate constant for the decomposition at 660 K is 4.5 X 10 s . (a) If we begin with an initial SO2CI2 pressure of 450 torr, what is the partial pressure of this substance after 60 s (b) At what time will the partial pressure of SO2CI2 decline to one-tenth its initial value ... 

Chlorine finally results from the decomposition of sulfuryl chloride ... 

Most unimolecular processes are apparently observed in the first-order (high-pressure or high-concentration) region, and we will continue to assume first-order kinetics for unimolecular steps in multistep mechanisms. Most proposed mechanisms do not include unimolecular steps, and there are not very many reactions known to have a one-step unimolecular mechanism. The first such reaction discovered was the isomerization of cyclopropane to propene. Others are the dissociation of molecular bromine and the decomposition of sulfuryl chloride. ... 

The decomposition of sulfuryl chloride, SO2CI2, to sulfur dioxide and chlorine gases is a first-order reaction. It is found that at a certain temperature, it takes 1.43 hours to decompose 0.0714 M to 0.0681 M. 

A novel ring contraction of 4,6-dihydro-3,7-diphenyl-5-(4-methylphenylsulfonyl)-l,2,5-triazepine (135, X = NTs) occurs under specific, monochlorination conditions <85H(23)1675>. An excess of chlorine or sulfuryl chloride in dichloromethane leads to the dichlorotriazepine derivative (136), but with one equivalent of sulfuryl chloride in dichloromethane, or one equivalent of NBS in carbon tetrachloride, formation of the dichlorotriazepine is minimized and up to 86% of4-tosylamino-3,6-diphenylpyridazine (137) is produced (Scheme 106). In polar solvents other, 5-membered ring, products are produced. Thermal decomposition of a series of 3,6-diaryl-2,7-dihydro-l,4,5-thia-diazepines (135, X = S) gave 3,6-disubstituted pyridazines in high yield <89BCJ2608>. 

Moissan and Lebeau (1901) produced sulfuryl fluoride by the combination of sulfur dioxide with fluorine (217). Other processes which have been used to produce the gas are (a) the thermal decomposition of barium fluorosulfonate or certain other fluorosulfonates (188, 221, 808), (b) the reaction of sulfur dioxide with chlorine and hydrogen fluoride in the presence of activated charcoal at 400° (11), (c) the reaction of sulfur dioxide and chlorine with potassium or sodium fluoride at 400° (328), (d) the disproportionation of sulfuryl chlorofluoride at 300-400° (328), (e) the reaction of sulfuryl chloride with a mixture of antimony trifluoride and antimony pentachloride at about 250° (86), (f) the reaction of sulfur dioxide with silver difluoride (86), (g) the reaction of thionyl fluoride with oxygen in an electrical discharge (314), (h) electrolysis of a solution of fluorosulfonic acid in hydrogen fluoride (264), ( ) the reaction of fluorine with sodium sulfate, sodium sulfite or sodium thiosulfate (229, 239), (j) the reaction of hydrogen fluoride with sulfuryl chloride (820). 

The quantitative decomposition of the reagent by mercury(ii) salts may be used for the manufacture of sulfuryl chloride. ... 

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. 

Hydroxyisothiazoles have been prepared from aminoketones and thionyl or sulfuryl chlorides,29 but have not been isolated from decomposition of 4-diazonium compounds.29,114... 

The trichlorocyclotrithiazene is obtained11 by stirring tetrasulfur tetranitride or S3N2C12 with excess sulfuryl chloride (2-3 mL per gram of sulfur compound) for ca. 24 hr at room temperature, in a flask fitted with an exit bubbler. After excess solvent has been removed by distillation (at ca. 20° under reduced pressure) and the residue has been pumped dry, the (NSC1)3 is obtained as a pale-yellow powder. Further purification is usually unnecessary but if analyses or a darker color indicate that some decomposition has occurred (e.g., through exposure to atmospheric moisture), it can be recrystallized from thionyl chloride or sulfuryl chloride. To obtain a good recovery, the mixture should be filtered at ca. —10°. 

Ethylsulfuryl chloride is similarly obtained by acting on ethyl alcohol with sulfuryl chloride and is a colorless liquid, of 1.44 specifii gravity, which boils with some decomposition at 135 C. (275 F,), yielding a vapor which lacrimates in concentrations as low as 1 1,000,000. A concentration of O.OSO mg. per liter is intolerable and a concentration of 1.00 mg. per liter is toxic. 

Sulfuryl chloride undergoes first-order decomposition at 320.°C with a half-life of 8.75 h. 

Chlorosulfonated polyolefins are prepared by interaction of the base resin with chlorine and either sulfur dioxide (18) or sulfiiryl chloride in the presence of a radical initiator (19). Sulfuryl chloride may be used alone as a chlorosulfonating agent, but must be accompanied by a catalytic amount of pyridine or other organic base. It has been proposed that the fimction of the organic base is to catalyze decomposition of the sulfuryl chloride molecule to form SO2 and CI2. However, the chlorosulfonation rate with base-catalyzed sulfuryl chloride is 5-10 times faster than that with gaseous chlorine and sulfur dioxide. So it is possible that the mechanism is more complex. In the latter case, the ratio of sulfonyl chloride to chlorine substituted onto the polymer backbone is, to some extent, a function of the amount of organic base added. The reaction temperature (lower reaction temperatures that result in higher sulfur utilities) also affects it (19). 

The following data have been generated in your laboratory for the decomposition of the very pungent sulfuryl chloride. 

Bridged Sulfonamides. The most convenient syntheses of 3-bridged pyrazole sulfonamides utilizes either a mercapto group or amine functionality as a handle to prepare the requisite sulfonamide. For example, one can prepare a pyrazole sulfonamide with many of the required substituents by the scheme depicted below. Condensation of methyl hydrazine with chloroacrylonitrile yields N-methyl-3-aminopyrazole 58 (12-13). The amine is protected by acylation. Chlorination at the 4 position with sulfuryl chloride, followed by deprotection provides 3-amino-4-chloropyrazole 59. The sulfonamide 60 is prepared by decomposition of the diazonium salt of 59 in SO2/CUCI followed by amination of the resulting sulfonyl chloride. 

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