696. Antimony Pentafluoride

Nomenclature

CAS number: 7783-70-2
Antimony fluoride (SbF5); pentafluoroantimony.
F5Sb; mol wt 216.75.
F 43.83%, Sb 56.18%.
SbF5.

Description and references

Lewis acid. Prepd industrially (in aluminum apparatus) according to the equation SbCl5 + 5HF → 5HCl + SbF5: Ruff, Plato, Ber. 37, 673 (1904); Perkins, Irwin, US 2410358 (1946). Laboratory procedure using SbF3 and F2: Woolf, Greenwood, J. Chem. Soc. 1950, 2200; Kwasnik in Handbook of Preparative Inorganic Chemistry Vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) p 200. Reviews: Burg in Fluorine Chemistry Vol. 1, J. Simons, Ed. (Academic Press, New York, 1950) pp 104-106; Kemmitt, Sharp, Adv. Fluorine Chem. 4, 210-211 (1965).

Properties

Hygroscopic, moderately viscous liquid. Poisonous, corrosive. mp 8.3°; bp 141°. d25.8 3.097; density data: Hoffman, Jolly, J. Phys. Chem. 61, 1574 (1957). Reacts violently with water. Also forms a solid dihydrate, which reacts violently with more water to form a clear soln. Slowly hydrolyzed in NaOH solns forming Sb(OH)6. Forms solids with sulfur chloride, carbon disulfide, benzene, toluene, petr ether (resin formation), ether, alc, acetone, ethyl acetate. Glacial acetic acid gives a clear soln. Slowly corrodes glass, copper, lead. May be stored in aluminum vessels.

Use

In the fluorination of organic compds, see the monograph Preparation, Properties and Technology of Fluorine and Organic Fluoro Compounds, C. Slesser, S. R. Schram, Eds. (McGraw-Hill, New York, 1951) 868 pp.