Phosgene

Phosgene^[1]

A sample case of toxic gases used in chemical warfare; the leftmost contains phosgene in a sealed capillary
Names
Preferred IUPAC name Carbonyl dichloride[2]
Other names Carbon dichloride oxide Carbon oxychloride Carbonyl chloride CG Chloroformyl chloride Collongite Dichloroformaldehyde Dichloromethanal Dichloromethanone
Identifiers
CAS Number	75-44-5 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:29365 Y
ChemSpider	6131 Y
ECHA InfoCard	100.000.792
EC Number	200-870-3
PubChem CID	6371
RTECS number	SY5600000
UNII	117K140075 Y
UN number	1076
CompTox Dashboard (EPA)	DTXSID0024260
InChI InChI=1S/CCl2O/c2-1(3)4 Y Key: YGYAWVDWMABLBF-UHFFFAOYSA-N Y InChI=1/CCl2O/c2-1(3)4 Key: YGYAWVDWMABLBF-UHFFFAOYAH
SMILES ClC(Cl)=O
Properties
Chemical formula	COCl2
Molar mass	98.91 g·mol−1
Appearance	Colorless gas
Odor	Suffocating, like musty hay or grass[3]
Density	4.248 g/L (15 °C, gas) 1.432 g/cm3 (0 °C, liquid)
Melting point	−118 °C (−180 °F; 155 K)
Boiling point	8.3 °C (46.9 °F; 281.4 K)
Solubility in water	Insoluble, reacts[4]
Solubility	Soluble in benzene, toluene, acetic acid Decomposes in alcohol and acid
Vapor pressure	1.6 atm (20°C)[3]
Magnetic susceptibility (χ)	−48·10−6 cm3/mol
Structure
Molecular shape	Trigonal planar
Dipole moment	1.17 D
Hazards
GHS labelling:
Pictograms	[5]
Signal word	Danger
Hazard statements	H314, H330[5]
Precautionary statements	P260, P280, P303+P361+P353+P315, P304+P340+P315, P305+P351+P338+P315, P403, P405[5]
NFPA 704 (fire diamond)	4 0 1
Flash point	Non-flammable
Threshold limit value (TLV)	0.1 ppm (1 ppm = 4 mg/m3)
Lethal dose or concentration (LD, LC):
LC50 (median concentration)	500 ppm (human, 1 min) 340 ppm (rat, 30 min) 438 ppm (mouse, 30 min) 243 ppm (rabbit, 30 min) 316 ppm (guinea pig, 30 min) 1022 ppm (dog, 20 min) 145 ppm (monkey, 1 min) 1 ppm is 4 mg/m3 [6]
LCLo (lowest published)	3 ppm (human, 2.83 h) 30 ppm (human, 17 min) 50 ppm (mammal, 5 min) 88 ppm (human, 30 min) 46 ppm (cat, 15 min) 50 ppm (human, 5 min) 2.7 ppm (mammal, 30 min) 1 ppm is 4 mg/m3 [6]
NIOSH (US health exposure limits):
PEL (Permissible)	TWA 0.1 ppm (0.4 mg/m3)[3]
REL (Recommended)	TWA 0.1 ppm (0.4 mg/m3) C 0.2 ppm (0.8 mg/m3) [15-minute][3]
IDLH (Immediate danger)	2 ppm[3] 1 ppm = 4 mg/m3
Safety data sheet (SDS)	[1]
Related compounds
Related compounds	Thiophosgene Formaldehyde Carbonic acid Urea Carbon monoxide Chloroformic acid Phosgene oxime
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Phosgene is an organic chemical compound with the formula COCl₂. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass.^[7] It can be thought of chemically as the double acyl chloride analog of carbonic acid, or structurally as formaldehyde with the hydrogen atoms replaced by chlorine atoms. In 2013, about 75–80 % of global phosgene was consumed for isocyanates, 18% for polycarbonates and about 5% for other fine chemicals.^[8]

Phosgene is extremely poisonous and was used as a chemical weapon during World War I, where it was responsible for 85,000 deaths. It is a highly potent pulmonary irritant and quickly filled enemy trenches due to it being a heavy gas.

It is classified as a Schedule 3 substance under the Chemical Weapons Convention. In addition to its industrial production, small amounts occur from the breakdown and the combustion of organochlorine compounds, such as chloroform.^[9]