Cyclooctatetraene

Cyclooctatetraene
Names
	Preferred IUPAC name Cycloocta-1,3,5,7-tetraene
	Other names [8]Annulene; (1Z,3Z,5Z,7Z)-Cycloocta-1,3,5,7-tetraene; 1,3,5,7-Cyclooctatetraene; COT
Identifiers
CAS Number	629-20-9 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:47034;
ChemSpider	553448 ;
ECHA InfoCard	100.010.074
EC Number	211-080-3;
PubChem CID	637866;
UNII	AJ19R479CQ;
CompTox Dashboard (EPA)	DTXSID9060867 ;
	InChI InChI=1S/C8H8/c1-2-4-6-8-7-5-3-1/h1-8H/b2-1-,3-1-,4-2-,5-3-,6-4-,7-5-,8-6-,8-7- Key: KDUIUFJBNGTBMD-BONZMOEMSA-N ; InChI=1/C8H8/c1-2-4-6-8-7-5-3-1/h1-8H/b2-1-,3-1-,4-2-,5-3-,6-4-,7-5-,8-6-,8-7- Key: KDUIUFJBNGTBMD-BONZMOEMBR;
	SMILES C1=C\C=C/C=C\C=C1;
Properties
Chemical formula	C8H8
Molar mass	104.15 g/mol
Appearance	Clear yellow
Density	0.9250 g/cm3, liquid
Melting point	−5 to −3 °C (23 to 27 °F; 268 to 270 K)
Boiling point	142 to 143 °C (288 to 289 °F; 415 to 416 K)
Solubility in water	immiscible
Magnetic susceptibility (χ)	−53.9·10−6 cm3/mol
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H225, H304, H315, H319, H335
Precautionary statements	P210, P233, P240, P241, P242, P243, P261, P264, P271, P280, P301+P310, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P312, P321, P331, P332+P313, P337+P313, P362, P370+P378, P403+P233, P403+P235, P405, P501
NFPA 704 (fire diamond)	3 3 0
Flash point	−11 °C (12 °F; 262 K)
Autoignition; temperature	561 °C (1,042 °F; 834 K)
Related compounds
Related hydrocarbons	Cyclooctane; Tetraphenylene
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

1,3,5,7-Cyclooctatetraene (COT) is an unsaturated derivative of cyclooctane. It is a colorless flammable liquid at room temperature. COT is an antiaromatic compound as it possesses 8 π electrons. In contrast to the aromaticity commonly seen in benzene rings; antiaromaticity destabilises the COT molecule. This destabilisation effect is so strong that COT avoids it by adopting a non-planar 'tub' conformation, which prevents all of the π orbitals from forming a single conjugated system. As a result, COT possesses significant polyene character and will undergo many reactions that benzene rings will not. This been the subject of much research and historically some controversy.