1,4-cyclohexadiene

Structural formula
General
Surname	1,4-cyclohexadiene
other names	1,4-dihydrobenzene; Cyclohexa-1,4-diene;
Molecular formula	C 6 H 8
Brief description	colorless liquid
External identifiers / databases
EC number	211-043-1
ECHA InfoCard	100.010.040
PubChem	12343
Wikidata	Q161523
properties
Molar mass	80.13 g mol −1
Physical state	liquid
density	0.86 g cm −3 (20 ° C)
Melting point	−50 ° C
boiling point	88-90 ° C
Refractive index	1.4725
safety instructions
H and P phrases	H: 225-340-350-373
	P: 201-210-308 + 313
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

1,4-Cyclohexadiene is a cyclic chemical compound . It consists of a six-membered ring that has two double bonds in positions one and four and thus belongs to the cycloalkenes .

presentation

1,4-Cyclohexadiene can be produced from benzene by a Birch reduction . For this purpose, benzene is reacted in liquid ammonia with elemental alkali metals , usually lithium or sodium , in the presence of a proton source such as tert-butanol or ammonium chloride. 1,4-Cyclohexadiene can also be obtained by double elimination of 1,4-dibromocyclohexane with a base , but the main product is 1,3-cyclohexadiene , which has conjugated double bonds.

properties

1,4-Cyclohexadiene is a colorless liquid that boils at 88–90 ° C.

The oxidation to benzene occurs easily. The driving force of the reaction is the formation of an aromatic system. It is suitable for reducing the radical intermediates that form in electron-transfer-mediated ring-opening reactions.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f data sheet 1,4-cyclohexadienes, 97% from Sigma-Aldrich , accessed on October 14, 2014 ( PDF ).
↑ GA Jeffrey, J. Buschmann, CW Lehmann, P. Luger, in: J. Am. Chem. Soc. , 1988 , 110 , pp. 7218-7219.
↑ W. Hückel; U. Wörffel: Reductions in liquid ammonia III. 1.2-Dimethyl-cyclohexadiene- (1.4) from o-xylene , in: Chem. Ber. , 1955 , 88 , pp. 338-345.
↑ K. Alder, F. Münz, in: Justus Liebigs Annalen der Chemie , 1949 , p. 130.
↑ W. Markownikow: Derivate der Naphten- oder Cyclohexanreihe , in: Justus Liebigs Annalen der Chemie , 1898 , 302 , pp. 1-42.

[aldrich-1] ↑ ^a ^b ^c ^d ^e ^f data sheet 1,4-cyclohexadienes, 97% from Sigma-Aldrich , accessed on October 14, 2014 ( PDF ).

[2] GA Jeffrey, J. Buschmann, CW Lehmann, P. Luger, in: J. Am. Chem. Soc. , 1988 , 110 , pp. 7218-7219.

[3] W. Hückel; U. Wörffel: Reductions in liquid ammonia III. 1.2-Dimethyl-cyclohexadiene- (1.4) from o-xylene , in: Chem. Ber. , 1955 , 88 , pp. 338-345.

[4] K. Alder, F. Münz, in: Justus Liebigs Annalen der Chemie , 1949 , p. 130.

[5] W. Markownikow: Derivate der Naphten- oder Cyclohexanreihe , in: Justus Liebigs Annalen der Chemie , 1898 , 302 , pp. 1-42.