Ethyl iodide

Ethyl iodide (also iodoethane) is a colorless flammable chemical compound. It has the chemical formula C₂H₅I and is prepared by heating ethanol with iodine and phosphorus.^[2] On contact with air, especially on the effect of light, it decomposes and turns yellow or reddish from dissolved iodine.

Ethyl iodide

Skeletal formula of ethyl iodide
Ball and stick model of ethyl iodide Spacefill model of ethyl iodide
Names
Preferred IUPAC name Iodoethane[1]
Identifiers
CAS Number	75-03-6 Y
3D model (JSmol)	Interactive image
Beilstein Reference	505934
ChEBI	CHEBI:42487 N
ChEMBL	ChEMBL1232588 N
ChemSpider	6100 Y
ECHA InfoCard	100.000.758
EC Number	200-833-1
PubChem CID	6340
RTECS number	KI4750000
UNII	59PO05D39L Y
CompTox Dashboard (EPA)	DTXSID9058783
InChI InChI=1S/C2H5I/c1-2-3/h2H2,1H3 Y Key: HVTICUPFWKNHNG-UHFFFAOYSA-N Y
SMILES CCI
Properties
Chemical formula	C2H5I
Molar mass	155.966 g·mol−1
Appearance	Colourless liquid
Density	1.940 g mL−1
Melting point	−111.10 °C; −167.98 °F; 162.05 K
Boiling point	71.5 to 73.3 °C; 160.6 to 163.8 °F; 344.6 to 346.4 K
Solubility in water	4 g L−1 (at 20 °C)
Solubility in ethanol	Miscible
Solubility in diethyl ether	Miscible
log P	2.119
Vapor pressure	17.7 kPa
Henry's law constant (kH)	1.8 μmol Pa−1 kg−1
Magnetic susceptibility (χ)	−69.7·10−6 cm3/mol
Refractive index (nD)	1.513–1.514
Viscosity	5.925 mPa s (at 20 °C)
Thermochemistry
Heat capacity (C)	109.7 J K−1 mol−1
Std enthalpy of formation (ΔfH⦵298)	−39.9 to −38.3 kJ mol−1
Std enthalpy of combustion (ΔcH⦵298)	−1.4629 to −1.4621 MJ mol−1
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H302, H315, H317, H319, H334, H335
Precautionary statements	P261, P280, P305+P351+P338, P342+P311
NFPA 704 (fire diamond)	2 1 1
Flash point	72 °C (162 °F; 345 K)
Lethal dose or concentration (LD, LC):
LD50 (median dose)	330 g m−3 (oral, rat)
Related compounds
Related iodoalkanes	Methyl iodide Diiodomethane Iodoform Carbon tetraiodide n-Propyl iodide Isopropyl iodide
Related compounds	Pimagedine Guanidine Diiodohydroxypropane
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

It may also be prepared by the reaction between hydroiodic acid and ethanol, typically by generating the hydroiodic acid in situ via an iodide salt (such as sodium iodide) and an acid (such as sulfuric acid), after which the ethyl iodide is distilled off. Ethyl iodide should be stored in the presence of copper powder to avoid rapid decomposition, though even with this method samples do not last more than 1 year.

Ethyl iodide distillation. It has a greenish color due to decomposition.

Because iodide is a good leaving group, ethyl iodide is an excellent ethylating agent. It is also used as the hydrogen radical promoter.

Production

Ethyl iodide is prepared by using red phosphorus, absolute ethanol and iodine. The iodine dissolves in the ethanol, where it reacts with the solid phosphorus to form phosphorus triiodide.^[3] During this process, the temperature is controlled.

3 C₂H₅OH + PI₃ → 3 C₂H₅I + H₃PO₃

The crude product is purified by distillation.