Iodoform

Iodoform

Names
Preferred IUPAC name Triiodomethane
Other names Iodoform
Identifiers
CAS Number	75-47-8 Y
3D model (Jmol)	Interactive image
Beilstein Reference	1697010
ChEBI	CHEBI:37758 Y
ChEMBL	ChEMBL1451116 N
ChemSpider	6134 Y
ECHA InfoCard	100.000.795
EC Number	200-874-5
KEGG	D01910 Y
MeSH	iodoform
PubChem	6374
RTECS number	PB7000000
UNII	KXI2J76489 Y
InChI InChI=1S/CHI3/c2-1(3)4/h1H Y Key: OKJPEAGHQZHRQV-UHFFFAOYSA-N Y
SMILES IC(I)I
Properties
Chemical formula	CHI3
Molar mass	393.73 g·mol−1
Appearance	Pale, light yellow, opaque crystals
Odor	Saffron-like
Density	4.008 g cm−3
Melting point	119 °C (246 °F; 392 K)
Boiling point	218 °C (424 °F; 491 K)
Solubility in water	100 mg L−1
Solubility in diethyl ether	136 g L−1
Solubility in acetone	120 g L−1
Solubility in ethanol	78 g L−1
log P	3.118
Henry's law constant (kH)	3.4 μmol Pa−1 kg−1
Magnetic susceptibility (χ)	-117.1·10−6 cm3/mol
Structure
Crystal structure	Hexagonal
Coordination geometry	Tetragonal
Molecular shape	Tetrahedron
Thermochemistry
Specific heat capacity (C)	157.5 J K−1 mol−1
Std enthalpy of formation (ΔfHo298)	180.1–182.1 kJ mol−1
Std enthalpy of combustion (ΔcHo298)	−716.9–−718.1 kJ mol−1
Pharmacology
ATC code	D09AA13 (WHO)
Hazards
GHS pictograms
GHS signal word	WARNING
GHS hazard statements	H315, H319, H335
GHS precautionary statements	P261, P280, P305+351+338
EU classification (DSD)	Xn
R-phrases	R20/21/22, R36/37/38
S-phrases	S26, S36/37
NFPA 704	0 2 1
Flash point	204 °C (399 °F; 477 K)
Lethal dose or concentration (LD, LC):
LD50 (median dose)	355 mg/kg (oral, rat) 1180 mg/kg (dermal, rat) 1.6 mmol/kg(s.c., mouse)
US health exposure limits (NIOSH):
PEL (Permissible)	none
REL (Recommended)	0.6 ppm (10 mg/m3)
IDLH (Immediate danger)	N.D.
Related compounds
Related haloalkanes	Methyl iodide Diiodomethane Carbon tetraiodide Chloroform Bromoform
Related compounds	Guanidine Pimagedine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Iodoform is the organoiodine compound with the formula CHI₃. A pale yellow, crystalline, volatile substance, it has a penetrating and distinctive odor (in older chemistry texts, the smell is sometimes referred to as the smell of hospitals, where the compound is still commonly used) and, analogous to chloroform, sweetish taste. It is occasionally used as a disinfectant. It is also known as tri-iodomethane, carbon triiodide, and methyl triiodide.

The molecule adopts tetrahedral molecular geometry with C_3vsymmetry.

The synthesis of iodoform was first described by Georges-Simon Serullas in 1822, by reactions of iodine vapour with steam over red hot coals, and also by reaction of potassium with ethanolic iodine in the presence of water; and at much the same time independently by John Thomas Cooper. It is synthesized in the haloform reaction by the reaction of iodine and sodium hydroxide with any one of these four kinds of organic compounds: a methyl ketone (CH₃COR), acetaldehyde (CH₃CHO), ethanol (CH₃CH₂OH), and certain secondary alcohols (CH₃CHROH, where R is an alkyl or aryl group).

The reaction of iodine and base with methyl ketones is so reliable that the "iodoform test" (the appearance of a yellow precipitate) is used to probe the presence of a methyl ketone. This is also the case when testing for specific secondary alcohols containing at least one methyl group in alpha-position.