Antimony pentachloride

Chemical compound

Names

IUPAC names

Antimony pentachloride
Antimony(V) chloride

Other names

Antimonic chloride
Antimony perchloride

Identifiers

CAS Number

7647-18-9^Y

3D model (JSmol)

Interactive image
Interactive image

ChemSpider

10613049^Y

ECHA InfoCard

100.028.729

EC Number

231-601-8

PubChem CID

24294

RTECS number

CC5075000

UNII

0S9308207L^Y

CompTox Dashboard (EPA)

DTXSID30893043

InChI

InChI=1S/5ClH.Sb/h5*1H;/q;;;;;+3/p-5^Y
Key: PZVOXSCNPLCIRA-UHFFFAOYSA-I^Y
InChI=1/5ClH.Sb.3H/h5*1H;;;;/q;;;;;+3;;;/p-5/r5ClH.H3Sb/h5*1H;1H3/q;;;;;+3/p-5
Key: KUGFODPTKMDJNG-MEZDTJOHAL
InChI=1/5ClH.Sb/h5*1H;/q;;;;;+3/p-5
Key: PZVOXSCNPLCIRA-AACRGIKGAS

SMILES

[Cl-].[Cl-].[Cl-].[Cl-].[Cl-].[SbH3+3]
[SbH3+3].[Cl-].[Cl-].[Cl-].[Cl-].[Cl-]

Properties

Chemical formula

Cl₅Sb

Molar mass

299.01 g·mol⁻¹

Appearance

colorless or reddish-yellow (fuming) liquid, oily

Odor

pungent, offensive

Density

2.336 g/cm³ (20 °C)^[1]
2.36 g/cm³ (25 °C)^[2]

Melting point

2.8 °C (37.0 °F; 275.9 K)

Boiling point

140 °C (284 °F; 413 K)
decomposes from 106 °C^[3]
79 °C (174 °F; 352 K)
at 22 mmHg^[1]
92 °C (198 °F; 365 K)
at 30 mmHg^[2]

Solubility in water

reacts

Solubility

soluble in alcohol, HCl, tartaric acid, CHCl₃, CS₂, CCl₄

Solubility in selenium(IV) oxychloride

62.97 g/100 g (25 °C)

Vapor pressure

0.16 kPa (25 °C)
4 kPa (40 °C)
7.7 kPa (100 °C)^[4]

Magnetic susceptibility (χ)

-120.0·10⁻⁶ cm³/mol

Refractive index (n_D)

1.59255

Viscosity

2.034 cP (29.4 °C)^[1]
1.91 cP (35 °C)

Structure

Molecular shape

Trigonal bipyramidal

Dipole moment

0 D

Thermochemistry^[3]

Heat capacity (C)

120.9 J/mol·K (gas)

Std molar
entropy (S^⦵₂₉₈)

295 J/mol·K

Std enthalpy of
formation (Δ_fH^⦵₂₉₈)

-437.2 kJ/mol

Gibbs free energy (Δ_fG^⦵)

-345.35 kJ/mol

Hazards

Occupational safety and health (OHS/OSH):

Inhalation hazards

Toxic

GHS labelling:^[2]

Pictograms

Signal word

Danger

Hazard statements

H314, H411

Precautionary statements

P273, P280, P305+P351+P338, P310

NFPA 704 (fire diamond)

Flash point

77 °C (171 °F; 350 K)

Lethal dose or concentration (LD, LC):

LD₅₀ (median dose)

1115 mg/kg, (rat, oral)^[3]

NIOSH (US health exposure limits):

PEL (Permissible)

TWA 0.5 mg/m³ (as Sb)^[5]

REL (Recommended)

TWA 0.5 mg/m³ (as Sb)^[5]

Related compounds

Other anions

Antimony pentafluoride

Other cations

Phosphorus pentachloride

Related compounds

Antimony trichloride

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

N verify (what is ^YN ?)

Infobox references

Chemical compound

Antimony pentachloride is a chemical compound with the formula SbCl₅. It is a colourless oil, but typical samples are yellowish due to dissolved chlorine. Owing to its tendency to hydrolyse to hydrochloric acid, SbCl₅ is a highly corrosive substance and must be stored in glass or PTFE containers.

Preparation and structure

Antimony pentachloride is prepared by passing chlorine gas into molten antimony trichloride:

SbCl₃ + Cl₂ → SbCl₅

Gaseous SbCl₅ has a trigonal bipyramidal structure.^[6]

Reactions

This compounds reacts with water to form antimony pentoxide and hydrochloric acid:^[7]

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 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.^[8]^[9]

It is also a strong oxidizing agent.^[10] For example aromatic ethers are oxidized to their radical cations according to the following stoichiometry:^[11]

3 SbCl₅ + 2 ArH → 2 (ArH+)(SbCl₆⁻) + SbCl₃

Applications

Antimony pentachloride is used as a polymerization catalyst 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.^[12]

References

^ ^a ^b ^c "Antimony pentachloride (UK PID)".
^ ^a ^b ^c Sigma-Aldrich Co., Antimony(V) chloride. Retrieved on 2014-05-29.
^ ^a ^b ^c "Antimony(V) chloride".
^ Antimony pentachloride 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 2014-05-29)
^ ^a ^b NIOSH Pocket Guide to Chemical Hazards. "#0036". National Institute for Occupational Safety and Health (NIOSH).
^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
^ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0-07-049439-8
^ V. Gutmann (1976). "Solvent effects on the reactivities of organometallic compounds". Coord. Chem. Rev. 18 (2): 225–255. doi:10.1016/S0010-8545(00)82045-7.
^ Cramer, R. E.; Bopp, T. T. (1977). "Graphical display of the enthalpies of adduct formation for Lewis acids and bases". Journal of Chemical Education. 54: 612–613. doi:10.1021/ed054p612. The plots shown in this paper used older parameters. Improved E&C parameters are listed in ECW model.
^ Connelly, N. G.; Geiger, W. E. (1996). "Chemical Redox Agents for Organometallic Chemistry". Chem. Rev. 96 (2): 877–922. doi:10.1021/cr940053x. PMID 11848774.
^ Rathore, R.; Kumar, A. S.; Lindeman, S. V.; Kochi, J. K. (1998). "Preparation and Structures of Crystalline Aromatic Cation-Radical Salts. Triethyloxonium Hexachloroantimonate as a Novel (One-Electron) Oxidant". The Journal of Organic Chemistry. 63 (17): 5847–5856. doi:10.1021/jo980407a. PMID 11672186.
^ Shekarchi, M.; Behbahani, F. K Catal. Lett. 2017 147 2950. doi:10.1007/s10562-017-2194-2