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| Names | |||
|---|---|---|---|
| Preferred IUPAC name Iodine monochloride Iodine(I) chloride | |||
| Systematic IUPAC name Chloroiodane | |||
| Other names Iodine chloride | |||
| Identifiers | |||
3D model (JSmol) | |||
| ChemSpider |
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| ECHA InfoCard | 100.029.306 | ||
| EC Number |
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| MeSH | Iodine-monochloride | ||
| UNII | |||
| UN number | 1792 | ||
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| Properties | |||
| ICl | |||
| Molar mass | 162.35 g/mol | ||
| Appearance | reddish-brown | ||
| Density | 3.10 g/cm3 | ||
| Melting point | 27.2 °C (81.0 °F; 300.3 K) (α-form) 13.9 °C (β-form) | ||
| Boiling point | 97.4 °C (207.3 °F; 370.5 K) | ||
| Hydrolyzes | |||
| Solubility | soluble inCS2 acetic acid pyridine alcohol,ether,HCl | ||
| −54.6×10−6 cm3/mol | |||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards | Corrosive, reacts with water to releaseHCl | ||
| Safety data sheet (SDS) | https://chemicalsafety.com/sds1/sdsviewer.php?id=30683304 | ||
| Related compounds | |||
Related interhalogen compounds | Chlorine monofluoride Bromine monochloride Iodine monobromide | ||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Iodine monochloride is aninterhalogen compound with theformulaICl. It is a red-brownchemical compound thatmelts nearroom temperature. Because of the difference in theelectronegativity ofiodine andchlorine, this molecule is highlypolar and behaves as a source of I+. Discovered in 1814 byGay-Lussac, iodine monochloride is the first interhalogen compound discovered.[1]
Iodine monochloride is produced simply by combining the halogens in a 1:1 molar ratio, according to the equation
Whenchlorine gas is passed through iodine crystals, one observes the brown vapor of iodine monochloride. Dark brown iodine monochloride liquid is collected. Excess chlorine converts iodine monochloride intoiodine trichloride in a reversible reaction:
ICl has twopolymorphs; α-ICl, which exists as black needles (red by transmitted light) with amelting point of 27.2 °C, and β-ICl, which exists as black platelets (red-brown by transmitted light) with a melting point 13.9 °C.[2]
In the crystal structures of both polymorphs the molecules are arranged in zigzag chains. β-ICl is monoclinic with thespace group P21/c.[3]
Iodine monochloride is soluble in acids such asHF andHCl but reacts with pure water to form HCl, iodine, andiodic acid:
ICl is a usefulreagent inorganic synthesis.[2] It is used as a source ofelectrophilic iodine in the synthesis of certainaromatic iodides.[4] It also cleaves C–Si bonds.
ICl will also add to thedouble bond inalkenes to give chloro-iodoalkanes.
When such reactions are conducted in the presence ofsodium azide, the iodo-azide RCH(I)–CH(N3)R′ is obtained.[5]
The Wijs solution, iodine monochloride dissolved in acetic acid, is used to determine theiodine value of a substance.
It can also be used to prepare iodates, by reaction with a chlorate. Chlorine is released as a byproduct.
Iodine monochloride is aLewis acid that forms 1:1adducts with Lewis bases such asdimethylacetamide andbenzene.
