Antimony pentachloride is a chemical compound with the formula SbCl₅. It is a colourless oil, but typical samples are yellowish due to dissolved

chlorine Chlorine is a chemical element; it has Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between ...

. Owing to its tendency to

hydrolyse Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis ...

hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ...

, SbCl₅ is a highly corrosive substance and must be stored in glass or

PTFE Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene, and has numerous applications because it is chemically inert. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a spin-off fro ...

containers.

Preparation and structure

Antimony pentachloride is prepared by passing

chlorine gas Chlorine is a chemical element; it has Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between ...

into molten

antimony trichloride Antimony trichloride is the chemical compound with the formula SbCl3. It is a soft colorless solid with a pungent odor and was known to alchemists as butter of antimony. Preparation Antimony trichloride is prepared by reaction of chlorine with a ...

: :SbCl₃ + Cl₂ → SbCl₅ Gaseous SbCl₅ has a trigonal bipyramidal structure.

Reactions

This compounds reacts with

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

to form

antimony pentoxide Antimony pentoxide (molecular formula: Sb2O5) is a chemical compound of antimony and oxygen. It contains antimony in the +5 oxidation state. Structure Antimony pentoxide has the same structure as the ''B'' form of niobium pentoxide and can be deri ...

and

: :2 SbCl₅ + 5 H₂O → Sb₂O₅ + 10 HCl The mono- and tetrahydrates are known, SbCl₅·H₂O and SbCl₅·4H₂O. This compound forms adducts with many Lewis bases. SbCl₅ is a soft Lewis acid and its

ECW model In chemistry, the ECW model is a semi-quantitative model that describes and predicts the strength of Lewis acid–Lewis base interactions. Many chemical reactions can be described as acid–base reactions, so models for such interactions are of pot ...

parameters are E_A = 3.64 and C_A = 10.42. It is used as the standard Lewis acid in the Gutmann scale of Lewis basicity. It is also a strong

oxidizing agent An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ''electron donor''). In ot ...

. For example aromatic ethers are oxidized to their radical cations according to the following stoichiometry: :3SbCl₅ + 2 ArH → 2(ArH+)(SbCl₆⁻) + SbCl₃

Applications

Antimony pentachloride is used as a

polymerization In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many fo ...

catalyst Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quick ...

and for the chlorination of organic compounds.

Precautions

Antimony pentachloride is a highly corrosive substance that should be stored away from heat and moisture. It is a chlorinating agent and, in the presence of moisture, it releases hydrogen chloride gas. Because of this, it may etch even stainless-steel tools (such as needles), if handled in a moist atmosphere. It should not be handled with non-fluorinated plastics (such as plastic syringes, plastic septa, or needles with plastic fittings), since it melts and carbonizes plastic materials.Shekarchi, M.; Behbahani, F. K ''Catal. Lett.'' 2017 ''147'' 2950. doi:10.1007/s10562-017-2194-2

References

External links

{{Chlorides Antimony(V) compounds Chlorides Metal halides Oxidizing agents