1,3-Cyclohexadiene

1,3-Cyclohexadiene
IUPAC name	Cyclohexa-1,3-diene
Other names	1,3-Cyclohexadiene, 1,2-Dihydrobenzene, 1,3-CHD
Identifiers
CAS number	592-57-4
PubChem	11605
ChEBI	37610
RTECS number	GU4702350
SMILES	C1CC=CC=C1
InChI	1/C6H8/c1-2-4-6-5-3-1/h1-4H,5-6H2
Properties
Molecular formula	C6H8−
Molar mass	80.13 g/mol
Appearance	Colourless liquid
Density	0.841 g/cm³
Melting point	−98 °C, 175 K, -144 °F
Boiling point	80 °C, 353 K, 176 °F
Hazards
EU classification	Flammable (F)
R-phrases	R11
S-phrases	S9 S16 S29 S33
Flash point	26 °C c.c.
Y(what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

1,3-Cyclohexadiene is a highly flammable cycloalkene that occurs as a colorless clear liquid. Its refractive index is 1.475 (20 °C, D).

It can be used as a hydrogen donor in transfer hydrogenation, since its conversion to benzene + hydrogen is in fact exothermic (−24.3 kJ/mol in the gas phase, as indicated by heats of hydrogenation).^[1][2] Despite this apparent instability with respect to benzene, the 1,3-cyclohexadiene motif is found in several natural products such as α-terpinene.

See also

• Benzene
• Cyclohexane
• 1,2-Cyclohexadiene
• 1,4-Cyclohexadiene
• Cyclohexene

References