Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound of tin and chlorine with the formula SnCl4. It is a colorless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other tin compounds.[1] It was first discovered by Andreas Libavius (1550–1616) and was known as spiritus fumans libavii.
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Names | |||
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IUPAC names
Tetrachlorostannane
Tin tetrachloride Tin(IV) chloride | |||
Other names
Stannic chloride
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Identifiers | |||
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3D model (JSmol)
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ChemSpider | |||
ECHA InfoCard | 100.028.717 | ||
EC Number |
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PubChem CID
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RTECS number |
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UNII | |||
UN number | 1827 | ||
CompTox Dashboard (EPA)
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Properties | |||
SnCl4 | |||
Molar mass | 260.50 g/mol (anhydrous) 350.60 g/mol (pentahydrate) | ||
Appearance | Colorless fuming liquid | ||
Odor | Acrid | ||
Density | 2.226 g/cm3 (anhydrous) 2.04 g/cm3 (pentahydrate) | ||
Melting point | −34.07 °C (−29.33 °F; 239.08 K) (anhydrous) 56 °C (133 °F; 329 K) (pentahydrate) | ||
Boiling point | 114.15 °C (237.47 °F; 387.30 K) | ||
hydrolysis,very hygroscopic (anhydrous) very soluble (pentahydrate) | |||
Solubility | soluble in alcohol, benzene, toluene, chloroform, acetone, kerosene, CCl4, methanol, gasoline, CS2 | ||
Vapor pressure | 2.4 kPa | ||
−115·10−6 cm3/mol | |||
Refractive index (nD)
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1.512 | ||
Structure | |||
monoclinic (P21/c) | |||
Hazards | |||
GHS labelling: | |||
Danger | |||
H314, H412 | |||
P260, P264, P273, P280, P301 P330 P331, P303 P361 P353, P304 P340, P305 P351 P338, P310, P321, P363, P405, P501 | |||
NFPA 704 (fire diamond) | |||
Safety data sheet (SDS) | ICSC 0953 | ||
Related compounds | |||
Other anions
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Tin(IV) fluoride Tin(IV) bromide Tin(IV) iodide | ||
Other cations
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Carbon tetrachloride Silicon tetrachloride Germanium tetrachloride Lead(IV) chloride | ||
Related compounds
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Tin(II) chloride | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Preparation
editIt is prepared from reaction of chlorine gas with tin at 115 °C (239 °F):
- Sn 2Cl
2 → SnCl
4
Structure
editAnhydrous tin(IV) chloride solidifies at −33 °C to give monoclinic crystals with the P21/c space group. It is isostructural with SnBr4. The molecules adopt near-perfect tetrahedral symmetry with average Sn–Cl distances of 227.9(3) pm.[2]
Reactions
editTin(IV) chloride is well known as a Lewis acid. Thus it forms hydrates. The pentahydrate SnCl4·5H2O was formerly known as butter of tin. They all consist of [SnCl4(H2O)2] molecules together with varying amounts of water of crystallization. The additional water molecules link together the molecules of [SnCl4(H2O)2] through hydrogen bonds.[3] Although the pentahydrate is the most common hydrate, lower hydrates have also been characterised.[4]
Aside from water, other Lewis bases form adducts with SnCl4. These include ammonia and organophosphines. The complex [SnCl6]2− is formed with hydrochloric acid making hexachlorostannic acid.[1]
Applications
editPrecursor to organotin compounds
editAnhydrous tin(IV) chloride is a major precursor in organotin chemistry. Upon treatment with Grignard reagents, tin(IV) chloride gives tetraalkyltin compounds:[5]
- SnCl4 4 RMgCl → SnR4 4 MgCl2
Anhydrous tin(IV) chloride reacts with tetraorganotin compounds in redistribution reactions:
- SnCl4 SnR4 → 2 SnCl2R2
These organotin halides are useful precursors to catalysts (e.g., dibutyltin dilaurate) and polymer stabilizers.[6]
Organic synthesis
editSnCl4 is used in Friedel–Crafts reactions as a Lewis acid catalyst.[1] For example, the acetylation of thiophene to give 2-acetylthiophene is promoted by tin(IV) chloride.[7] Similarly, tin(IV) chloride is useful for the nitrations.[8]
Safety
editStannic chloride was used as a chemical weapon in World War I, as it formed an irritating (but non-deadly) dense smoke on contact with air. It was supplanted by a mixture of silicon tetrachloride and titanium tetrachloride near the end of the war due to shortages of tin.[9]
References
edit- ^ a b c Egon Wiberg, Nils Wiberg, Arnold Frederick Holleman (2001). Inorganic Chemistry. Elsevier. ISBN 0-12-352651-5.
{{cite book}}
: CS1 maint: multiple names: authors list (link) - ^ Reuter, Hans; Pawlak, Rüdiger (April 2000). "Die Molekül- und Kristallstruktur von Zinn(IV)-chlorid". Zeitschrift für anorganische und allgemeine Chemie (in German). 626 (4): 925–929. doi:10.1002/(SICI)1521-3749(200004)626:4<925::AID-ZAAC925>3.0.CO;2-R.
- ^ Barnes, John C.; Sampson, Hazel A.; Weakley, Timothy J. R. (1980). "Structures of di-μ-hydroxobis[aquatrichlorotin(IV)]-1,4-dioxane(1/3), di-μ-hydroxobis[aquatrichlorotin(IV)]-1,8-epoxy-p-menthane(1/4), di-m-hydroxobis[aquatribromotin(IV)]-1,8-epoxy-p-menthane(1/4), di-μ-hydroxobis[aquatrichlorotin(IV)], and cis-diaquatetrachlorotin(IV)". J. Chem. Soc., Dalton Trans. (6): 949. doi:10.1039/DT9800000949.
- ^ Genge, Anthony R. J.; Levason, William; Patel, Rina; et al. (2004). "Hydrates of tin tetrachloride". Acta Crystallographica Section C. 60 (4): i47–i49. doi:10.1107/S0108270104005633. PMID 15071197.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
- ^ G. G. Graf "Tin, Tin Alloys, and Tin Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2005 Wiley-VCH, Weinheim. doi:10.1002/14356007.a27_049
- ^ John R. Johnson, G. E. May (1938). "2-Acetothienone". Organic Syntheses. 18: 1. doi:10.15227/orgsyn.018.0001.
- ^ Thurston, David E.; Murty, Varanasi S.; Langley, David R.; Jones, Gary B. (1990). "O-Debenzylation of a Pyrrolo[2,1-c][1,4]benzodiazepine in the Presence of a Carbinolamine Functionality: Synthesis of DC-81". Synthesis. 1990: 81–84. doi:10.1055/s-1990-26795. S2CID 98109571.
- ^ Fries, Amos A. (2008). Chemical Warfare. Read. pp. 148–49, 407. ISBN 978-1-4437-3840-8..
External links
edit- International Chemical Safety Card 0953
- tinchemical.com/products (industrial uses) at the Wayback Machine (archived 2005-02-28)