Selenium oxydichloride

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Selenium oxydichloride
Structure of the selenium oxydichloride molecule 3D model of the selenium oxydichloride molecule
CAS number 7791-23-3 YesY
PubChem 24647
EC number 232-244-0
RTECS number VS7000000
Jmol-3D images Image 1
Molecular formula SeOCl2
Molar mass 165.87 g/mol
Appearance colorless liquid
Density 2.43 g/cm3, liquid
Melting point 10.9 °C
Boiling point 177.2 °C
Refractive index (nD) 1.651 (20 °C)
Molecular shape trigonal pyramidal
R-phrases 14-23/25-33-35-50/53
S-phrases 26-36/37/39-45-60-61
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g., calcium Special hazards (white): no codeNFPA 704 four-colored diamond
Related compounds
Related compounds SOCl2, POCl3
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

Selenium oxydichloride is the inorganic compound with the formula SeOCl2. It is a liquid with a high dielectric constant (55) and high specific conductance, and for these reasons is an attractive solvent. Structurally, it is a close chemical relative of thionyl chloride SOCl2 and DMSO as a donor solvent.

Preparation and reactions[edit]

Selenium oxydichloride can be prepared by several methods, and a popular one involves the conversion of selenium dioxide to dichloroselenious acid followed by dehydration:[1]

SeO2 + 2 HCl → Se(OH)2Cl2
Se(OH)2Cl2 → SeOCl2 + H2O

The original synthesis involved the redistribution reaction of selenium dioxide and selenium tetrachloride.

The compound hydrolyzes readily.

See also[edit]


  1. ^ G. B. L. Smith, Julius Jackson, J. J. Pitha, Eva Blanchard "Selenium(IV) Oxychloride" Inorganic Syntheses, 1950, Volume 3, pp. 130–137.doi:10.1002/9780470132340.ch34