Cycloheptene

Cycloheptene is a 7-membered cycloalkene with a flash point of −6.7 °C. It is a raw material in organic chemistry and a monomer in polymer synthesis.^{[not in body]} Cycloheptene can exist as either the cis- or the trans-isomer.

cis-Cycloheptene^[1]

Names
Preferred IUPAC name Cycloheptene
Other names cis-Cycloheptene
Identifiers
CAS Number	628-92-2 Y
3D model (JSmol)	Interactive image
ChemSpider	11857 Y
ECHA InfoCard	100.010.056
PubChem CID	12363
UNII	KRY3SY05AH Y
CompTox Dashboard (EPA)	DTXSID4074560
InChI InChI=1S/C7H12/c1-2-4-6-7-5-3-1/h1-2H,3-7H2 Y Key: ZXIJMRYMVAMXQP-UHFFFAOYSA-N Y InChI=1/C7H12/c1-2-4-6-7-5-3-1/h1-2H,3-7H2 Key: ZXIJMRYMVAMXQP-UHFFFAOYAQ
SMILES C\1=C\CCCCC/1
Properties
Chemical formula	C7H12
Molar mass	96.17 g/mol
Density	0.824 g/cm3
Boiling point	112 to 114.7 °C (233.6 to 238.5 °F; 385.1 to 387.8 K)
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

trans-Cycloheptene

Under normal conditions, the cycloheptene double bond forms the cis isomer. However, the unstable trans isomer is an accessible reactive intermediate. Methyl benzoate catalyzes singlet photosensitization; irradiating cis-cycloheptene and it with ultraviolet light at −35 °C produces a detectible trans-cycloheptene population.^[2]

The anti-Bredt trans isomer is very strained,^[3] and the unsaturated carbons are partly pyramidal. The pyramidalization angle is estimated at 37° and the p orbital misalignment 30.1°. The isomer decomposes facily through a dimolecular, diradical pathway, even at temperatures too low for double-bond rotation.^[2]