Cyclohexylbenzene (or phenylhexamethylene, as it was initially called) is the
organic compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...
with the structural formula . It is a derivative of benzene with a
cyclohexyl substituent (C
6H
11). It is a colorless liquid.
History and synthesis
Cyclohexylbenzene was first obtained in 1899 by
Markovnikov Markovnikov () is a Russian masculine surname, which originates from ''морковь'' (''carrot''); its feminine counterpart is Markovnikova. It may refer to
* Vladimir Markovnikov (1837–1904), Russian chemist
* Nikolai Markovnikov (1869–1942) ...
's student Nikolay Kirsanov (1874–1921). He used a
Friedel–Crafts alkylation of benzene with
cyclohexyl chloride using a catalyst such as
aluminum trichloride:
:
Cyclohexylbenzene is now industrially produced by the acid-catalyzed alkylation of
benzene
Benzene is an Organic compound, organic chemical compound with the Chemical formula#Molecular formula, molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal Ring (chemistry), ring with one hyd ...
with
cyclohexene
Cyclohexene is a hydrocarbon with the formula . It is a cycloalkene. At room temperature, cyclohexene is a colorless liquid with a sharp odor. Among its uses, it is an chemical intermediate, intermediate in the commercial synthesis of nylon.
Prod ...
. The process can proceed using benzene as the exclusive organic precursor. Its partial hydrogenation gives cyclohexene, which alkylates the unhydrogenated benzene.
It is also generated by the
hydrodesulfurization
Hydrodesulfurization (HDS), also called hydrotreatment or hydrotreating, is a catalytic chemical process widely used to desulfurization, remove sulfur (S) from natural gas and from oil refinery, refined petroleum products, such as gasoline, g ...
of
dibenzothiophene
Dibenzothiophene (DBT, diphenylene sulfide) is the organosulfur compound consisting of two benzene rings fused to a central thiophene ring. It has the chemical formula C12H8S. It is a colourless solid that is chemically somewhat similar to anth ...
, and
ExxonMobil
Exxon Mobil Corporation ( ) is an American multinational List of oil exploration and production companies, oil and gas corporation headquartered in Spring, Texas, a suburb of Houston. Founded as the Successors of Standard Oil, largest direct s ...
took a patent in 2009 for a process based on direct hydroalkylation of two benzene molecules.
Applications
A route to phenol analogous to the
cumene process
The cumene process (cumene-phenol process, Hock process) is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene (isopropyl benzene), the intermediate material during the process. It ...
begins with cyclohexylbenzene, which is
oxidized
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is ...
to a
hydroperoxide
Hydroperoxides or peroxols are Chemical compound, compounds of the form ROOH, where R stands for any group, typically Organic compound, organic, which contain the hydroperoxy functional group (). Hydroperoxide also refers to the hydroperoxide anio ...
, akin to the production of
cumene hydroperoxide
Cumene hydroperoxide is the organic compound with the formula C6H5C(CH3)2OOH; this oily liquid is classified as an organic hydroperoxide. Products of decomposition of cumene hydroperoxide are methylstyrene, acetophenone, and 2-phenylpropan-2- ...
. Via the Hock rearrangement, cyclohexylbenzene hydroperoxide cleaves to give phenol and
cyclohexanone
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has a sweet odor reminiscent of benzaldehyde. Over time, samples of ...
:
:
Cyclohexanone is an important precursor to some
nylon
Nylon is a family of synthetic polymers characterised by amide linkages, typically connecting aliphatic or Polyamide#Classification, semi-aromatic groups.
Nylons are generally brownish in color and can possess a soft texture, with some varieti ...
s.
[{{Ullmann, doi=10.1002/14356007.a19_299.pub3, title=Phenol, year=2004, last1=Weber, first1=Manfred, last2=Weber, first2=Markus, last3=Kleine-Boymann, first3=Michael]
References
Cyclohexyl compounds
Phenyl compounds