9348. Thionyl Chloride

Nomenclature

CAS number: 7719-09-7
Sulfurous oxychloride.
Cl2OS; mol wt 118.97.
Cl 59.60%, O 13.45%, S 26.95%.
SOCl2.

Description and references

Prepn by the oxidation of sulfur dichloride with sulfur trioxide: Michaelis, Ann. 274, 173 (1893); Edwards, US 2362057 (1944 to Hooker Electrochemical); Fehér in Handbook of Preparative Inorganic Chemistry vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) pp 382-383; Macaluso, “Sulfur Compounds” in Kirk-Othmer Encyclopedia of Chemical Technology vol. 19 (Interscience, New York, 2nd ed., 1969) pp 398-401. Purification by distilling from quinoline and boiled linseed oil: Martin, Fieser, Org. Synth. coll. vol. II, 570 (1943). Alternate methods of purification: Cottle, J. Am. Chem. Soc. 68, 1380 (1946); Kunkel; Rosenberg, Flaxman, US 3155457; US 3156529 (both 1964 to Hooker Chem.); Friedman, Wetter, J. Chem. Soc. A 1967, 36.

Properties

Colorless to pale yellow or reddish, fuming, refractive liquid. Corrosive. Suffocating odor. d40 1.676; d410 1.655; d420 1.638. mp 104.5°. bp760 76°; bp96.6 20°. nD20 1.517. Dec when heated above 140° forming Cl2, SO2, and S2Cl2. Hydrolyzed by water forming SO2 and HCl. Miscible with benzene, chloroform, carbon tetrachloride.

Caution

Potential symptoms of overexposure are irritation of eyes, skin, mucous membranes; eye, skin burns. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 306.

Use

For making acyl chlorides, to replace OH or SH groups with chlorine atoms; reacts with Grignard reagents to form the corresp sulfoxides. Review of use in organic synthesis: J. S. Pizey, Synthetic Reagents vol. 1 (John Wiley, New York, 1974) pp 321-357.