Hexachlorocyclohexa-2,5-dien-1-one

Hexachlorocyclohexa-2,5-dien-1-one, sometimes informally called hexachlorophenol (HCP), is an organochlorine compound. It can be prepared from phenol. Despite the informal name, the compound is not a phenol but is a ketone.^[2] The informal name is derived from its method of preparation which includes phenol as a reagent.

Hexachlorocyclohexa-2,5-dien-1-one

Structural formula of hexachlorocyclohexa-2,5-dien-1-one
Names
Preferred IUPAC name 2,3,4,4,5,6-Hexachlorocyclohexa-2,5-dien-1-one
Other names Hexachlorophenol
Identifiers
CAS Number	599-52-0 Y
3D model (JSmol)	Interactive image Interactive image
Abbreviations	HCP
ChemSpider	62251 Y
PubChem CID	69029
RTECS number	SN1575000
CompTox Dashboard (EPA)	DTXSID10208611
InChI InChI=1S/C6Cl6O/c7-1-3(13)2(8)5(10)6(11,12)4(1)9 Key: SLKWROUNLHVIIQ-UHFFFAOYSA-N
SMILES ClC1=C(Cl)C(Cl)(Cl)C(Cl)=C(Cl)C1=O O=C1C(=C(Cl)C(Cl)(Cl)C(=C1Cl)Cl)Cl
Properties
Chemical formula	C6Cl6O
Molar mass	300.77 g·mol−1
Melting point	113 °C (235 °F; 386 K)
Hazards[1]
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P280, P302+P352, P305+P351+P338
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

HCP is normally produced by chlorination of phenol by chlorine in the presence of metal chloride catalyst, such as ferric chloride. It can also be produced by alkaline hydrolysis of polychlorinated benzenes at high temperature and pressure, by conversion of diazonium salts of chlorinated anilines, or by chlorination of phenolsulfonic acids and benzenesulfonic acids followed by removal of the sulfonic acid group. The hydrolysis of HCP gives chloranil.^[3]