Cyclohexa-1,4-diene
Appearance
![]() | |
Names | |
---|---|
Systematic IUPAC name
Cyclohexa-1,4-diene[1] | |
Other names | |
Identifiers | |
3D model (JSmol)
|
|
Abbreviations | 1,4-CHDN |
1900733 | |
ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.010.040 |
EC Number |
|
1656 | |
MeSH | 1,4-cyclohexadiene |
PubChem CID
|
|
UN number | 3295 |
CompTox Dashboard (EPA)
|
|
| |
| |
Properties | |
C6H8 | |
Molar mass | 80.130 g·mol−1 |
Appearance | Colorless liquid |
Density | 847 mg cm-3 |
Melting point | −50 °C; −58 °F; 223 K |
Boiling point | 82 °C; 179 °F; 355 K |
Refractive index (nD)
|
1.472 |
Thermochemistry | |
Heat capacity (C)
|
142.2 J K-1 mol-1 |
Std molar
entropy (S⦵298) |
189.37 J K-1 mol-1 |
Std enthalpy of
formation (ΔfH⦵298) |
63.0-69.2 kJ mol-1 |
Std enthalpy of
combustion (ΔcH⦵298) |
-3573.5--3567.5 kJ mol-1 |
Hazards | |
GHS labelling: | |
![]() ![]() | |
Danger | |
H225, H340, H350, H373 | |
P201, P210, P308+P313 | |
NFPA 704 (fire diamond) | |
Flash point | -7 °C |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
1,4-Cyclohexadiene is a highly flammable cycloalkene that occurs as a colorless clear liquid.
1,4-Cyclohexadiene and related compounds may be prepared from benzene using lithium or sodium in liquid ammonia, this process being known as a Birch reduction. However 1,4-cyclohexadiene is easily oxidised to benzene, the driving force being the formation of an aromatic ring. The conversion to an aromatic system may be performed in the laboratory using an alkene such as styrene, along with a hydrogen transfer agent such as palladium metal supported on charcoal.
γ-Terpinene is a naturally occurring derivative of 1,4-cyclohexadiene, found in the essential oils of coriander, lemon, and cumin.
References
- ^ "1,4-cyclohexadiene - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 27 March 2005. Identification and Related Records. Retrieved 12 October 2011.
External links
- The photochemistry of 1,4-cyclohexadiene in solution and in the gas phase
- NIST Chemistry WebBook Reaction thermochemistry data