Thionyl chloride

Thionyl chloride
Ball-and-stick model of thionyl chloride
Names
IUPAC name
Thionyl chloride
Other names
  • Thionyl dichloride
  • Sulfurous oxychloride
  • Sulfinyl chloride
  • Sulfinyl dichloride
  • Dichlorosulfoxide
  • Sulfur oxide dichloride
  • Sulfur monoxide dichloride
  • Sulfuryl(IV) chloride
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.028.863 Edit this at Wikidata
EC Number
  • 231-748-8
RTECS number
  • XM5150000
UNII
UN number 1836
  • InChI=1S/Cl2OS/c1-4(2)3 checkY
    Key: FYSNRJHAOHDILO-UHFFFAOYSA-N checkY
  • InChI=1/Cl2OS/c1-4(2)3
    Key: FYSNRJHAOHDILO-UHFFFAOYAN
  • ClS(Cl)=O
Properties
SOCl2
Molar mass 118.97 g/mol
Appearance Colourless liquid (yellows on ageing)
Odor Pungent and unpleasant
Density 1.638 g/cm3, liquid
Melting point −104.5 °C (−156.1 °F; 168.7 K)
Boiling point 74.6 °C (166.3 °F; 347.8 K)
Reacts
Solubility Soluble in most aprotic solvents: toluene, chloroform, diethyl ether. Reacts with protic solvents such as alcohols
Vapor pressure
  • 384 Pa (−40 °C)
  • 4.7 kPa (0 °C)
  • 15.7 kPa (25 °C)[1]
1.517 (20 °C)[2]
Viscosity 0.6 cP
Structure
pyramidal
1.44 D
Thermochemistry
121.0 J/mol (liquid)[3]
309.8 kJ/mol (gas)[3]
−245.6 kJ/mol (liquid)[3]
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Very toxic, corrosive, releases HCl on contact with water
GHS labelling:
GHS05: CorrosiveGHS07: Exclamation markGHS06: Toxic
Danger
H302, H314, H331
P261, P280, P305+P351+P338, P310
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 0: Will not burn. E.g. waterInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard W: Reacts with water in an unusual or dangerous manner. E.g. sodium, sulfuric acid
4
0
2
W
Flash point Non-flammable
NIOSH (US health exposure limits):
PEL (Permissible)
 None[4]
REL (Recommended)
 C 1 ppm (5 mg/m3)[4]
IDLH (Immediate danger)
 N.D.[4]
Related compounds
Related Thionyl halides
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Thionyl chloride is an inorganic compound with the chemical formula SOCl2. It is a moderately volatile, colourless liquid with an unpleasant acrid odour. Thionyl chloride is primarily used as a chlorinating reagent, with approximately 45,000 tonnes (50,000 short tons) per year being produced during the early 1990s,[5] but is occasionally also used as a solvent.[6][7][8] It is toxic, reacts with water, and is also listed under the Chemical Weapons Convention as it may be used for the production of chemical weapons.

Thionyl chloride is sometimes confused with sulfuryl chloride, SO2Cl2, but the properties of these compounds differ significantly. Sulfuryl chloride is a source of chlorine whereas thionyl chloride is a source of chloride ions.

  1. ^ Thionyl chloride in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD) (retrieved 2014-05-11)
  2. ^ Patnaik, Pradyot (2003). Handbook of Inorganic Chemicals. New York, NY: McGraw-Hill. ISBN 0-07-049439-8.
  3. ^ a b c Lide, David R.; et al., eds. (1996). CRC Handbook of Chemistry and Physics (76th ed.). Boca Raton, FL: CRC Press. pp. 5–10. ISBN 0-8493-0476-8.
  4. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0611". National Institute for Occupational Safety and Health (NIOSH).
  5. ^ Lauss, H.-D.; Steffens, W. "Sulfur Halides". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a25_623. ISBN 978-3527306732.
  6. ^ Oka, Kitaro (1981). "Some Applications of Thionyl Chloride in Synthetic Organic Chemistry". Synthesis. 1981 (9): 661–681. doi:10.1055/s-1981-29563. S2CID 94917739.
  7. ^ Calderazzo, Fausto; Dell'Amico, Daniela Belli (April 1981). "Syntheses of carbonyl halides of late transition elements in thionyl chloride as solvent. Carbonyl complexes of palladium(II)". Inorganic Chemistry. 20 (4): 1310–1312. doi:10.1021/ic50218a072.
  8. ^ Garber, E. B.; Pease, L. E. D.; Luder, W. F. (20 April 1953). "Titration of Aprotic Acids in Thionyl Chloride". Analytical Chemistry. 25 (4): 581–583. doi:10.1021/ac60076a012.