Iodine monochloride
From Wikipedia, the free encyclopedia
Iodine monochloride | |
---|---|
IUPAC name | iodine(I) chloride |
Other names | iodine chloride |
Identifiers | |
CAS number | [7790-99-0] |
SMILES | ICl |
Properties | |
Molecular formula | ICl |
Molar mass | 162.35 g/mol |
Appearance | red to brown liquid |
Density | 3.10 g/cm3 |
Melting point |
27°C (α-form) |
Boiling point |
97.4°C (370.6 K) |
Solubility in water | hydrolysis |
Solubility in other solvents | carbon disulfide acetic acid pyridine |
Hazards | |
MSDS | External MSDS |
Main hazards | corrosive |
Related compounds | |
Related interhalogen compounds | Chlorine monofluoride, bromine monochloride, iodine monobromide |
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
Iodine monochloride is the chemical compound with the formula ICl. It is a red-brown compound that melts near room temperature. Because of the difference in the electronegativity of iodine and chlorine, ICl is highly polar and behaves as a source of “I+.”
Preparation of iodine monochloride entails simply combining the halogens in a 1:1 molar ratio, according to the equation
- I2 + Cl2 → 2 ICl
When chlorine 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 into iodine trichloride in a reversible reaction:
- ICl + Cl2 → ICl3
[edit] Polymorphs
ICl has two polymorphs; α-ICl which exists as black needles (red by transmitted light) with a melting 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.[1]
[edit] Uses
ICl is a useful reagent in organic synthesis.[1] It is used as a source of electrophilic iodine in the synthesis of certain aromatic iodides.[2] It also cleaves C-Si bonds.
ICl will also add to the double bond in alkenes to give chloro-iodo alkanes.
- RCH=CHR’ + ICl → RCH(I)-CH(Cl)R’
When such reactions are conducted in the presence of sodium azide, the iodo-azide RCH(I)-CH(N3)R’ is obtained.[3]
[edit] References
- ^ a b Brisbois, R. G.; Wanke, R. A.; Stubbs, K. A.; Stick, R. V. “Iodine Monochloride” Encyclopedia of Reagents for Organic Synthesis, 2004 John Wiley & Sons. DOI: 10.1002/047084289X.ri014
- ^ Wallingford, V. H.; Krüger, P. A. (1943). "5-Iodo-anthranilic Acid". Org. Synth.; Coll. Vol. 2: 349.
- ^ Padwa, A.; Blacklock, T.; Tremper, A.. "3-Phenyl-2H-Azirine-2-carboxaldehyde". Org. Synth.; Coll. Vol. 6: 893.