Sulfuryl chloride

Synthesis

SO2Cl2 is prepared by the reaction of sulfur dioxide and chlorine in the presence of a catalyst, such as activated carbon. :SO2 + Cl2 → SO2Cl2

The product can be purified by fractional distillation.

Legacy routes

Sulfuryl chloride was first prepared in 1838 by the French chemist Henri Victor Regnault.

• Reprinted as:

Older routes include oxidation of thionyl chloride: :5 SOCl2 + HgO → ClSSCl + HgCl2 + 3 SO2Cl2 :2 SOCl2 + MnO2 → SO2 + MnCl2 + SO2Cl2

Reactions

Sulfuryl chloride reacts with water, releasing hydrogen chloride gas and sulfuric acid: :2 H2O + SO2Cl2 → 2 HCl + H2SO4

For sulfuryl chloride, this happens at room temperature, but the related sulfuryl fluoride does not hydrolyse at temperatures up to 150 °C.

SO2Cl2 will also decompose when heated to or above 100 °C, about 30 °C above its boiling point.

Upon standing, SO2Cl2 decomposes to sulfur dioxide and chlorine, which gives the older samples a slightly yellowish color.

SO2Cl2 can be used as a source of chlorine in alkane radical chlorination, initiated chemically (usually by peroxide) or by light:

:CH4 + SO2Cl2 → CH3Cl + SO2 + HCl

Uses

Sulfuryl chloride is used as a source of Cl2. Because it is a pourable liquid, it is considered more convenient than Cl2 to dispense.

Sulfuryl chloride is used in the conversion of C−H to C−Cl adjacent to activating substituents such as carbonyls and sulfoxides: : It also chlorinates alkanes, alkenes, alkynes, aromatics, ethers (such as tetrahydrofuran) and epoxides. Such reactions occur under free radical conditions using an initiator such as AIBN. It convert thiols or disulfides into the corresponding sulfenyl chlorides: :

Occasionally, sulfinyl chlorides result from such reactions. SO2Cl2 can also convert alcohols to alkyl chlorides. In industry, sulfuryl chloride is most used in producing pesticides. Phosphorus pentachloride is prepared by the reaction of white phosphorus with sulfuryl chloride.

Sulfuryl chloride can also be used to treat wool to prevent shrinking.

Precautions

Sulfuryl chloride is toxic, corrosive, and acts as a lachrymator. It releases hydrogen chloride upon contact with water, as well as donor solvents such as dimethyl sulfoxide and dimethylformamide.

References

References

1. Patnaik, P.. (September 2017). "Handbook of Inorganic Chemicals". McGraw-Hill.
2. F. Fehér. (1963). "Handbook of Preparative Inorganic Chemistry, 2nd Ed.". Academic Press.
3. "Basic Principles of Organic Chemistry".
4. Mark Lautens, Giliane Bouchain. (2002). "[4+3] Cycloaddition in Water. Synthesis of 2,4-endo,endo-Dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one". Organic Syntheses.
5. (1960). "3-Hydroxyquinoline". Organic Syntheses.
6. (1990). "(Phenylthio)Nitromethane". Organic Syntheses.
7. (1995). "Synthesis: Carbon with One Heteroatom Attached by a Single Bond". [[Elsevier]].