2,2-Dimethylbutane, trivially known as neohexane at
William Odling's 1876 suggestion, is an
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 formula C
6H
14 or (H
3C-)
3-C-CH
2-CH
3. It is therefore an
alkane
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in whi ...
, indeed the most compact and branched of the
hexane
Hexane () or ''n''-hexane is an organic compound, a straight-chain alkane with six carbon atoms and the molecular formula C6H14.
Hexane is a colorless liquid, odorless when pure, and with a boiling point of approximately . It is widely used as ...
isomers — the only one with a
quaternary carbon and a
butane
Butane () is an alkane with the formula C4H10. Butane exists as two isomers, ''n''-butane with connectivity and iso-butane with the formula . Both isomers are highly flammable, colorless, easily liquefied gases that quickly vaporize at ro ...
(C
4) backbone.
Synthesis
Butlerov's student V. Goryainov originally discovered neohexane in 1872 by
cross-coupling of
zinc ethyl with tert-butyl iodide.
2,2-Dimethylbutane can be synthesised by the hydroisomerisation of
2,3-dimethylbutane using an acid catalyst.
It can also be synthesised by isomerization of
''n''-pentane in the presence of a catalyst containing combinations of one or more of palladium, platinum, rhodium and rhenium on a matrix of zeolite, alumina, silicon dioxide or other materials. Such reactions create a mixture of final products including isopentane, ''n''-hexane, 3-methylpentane, 2-methylpentane, 2,3-dimethylbutane and 2,2-dimethylbutane. Since the composition of the final mixture is temperature dependant the desired final component can be obtained choice of catalyst and by combinations of temperature control and distillations.
Uses
Neohexane is used as a
high-octane anti-knock additive in
gasoline
Gasoline ( North American English) or petrol ( Commonwealth English) is a petrochemical product characterized as a transparent, yellowish, and flammable liquid normally used as a fuel for spark-ignited internal combustion engines. When for ...
and in the manufacture of agricultural chemicals.
It is also used in a number of commercial, automobile and home maintenance products, such as adhesives, electronic contact cleaners and upholstery polish sprays.
In laboratory settings, it is commonly used as a probe molecule in techniques which study the active sites of metal catalysts. Such catalysts are used in hydrogen-deuterium exchange, hydrogenolysis, and isomerization reactions. It is well suited to this purpose as 2,2-dimethylbutane contains both an isobutyl and an ethyl group.
See also
*
Methylbutane (isopentane)
*
2-Methylpentane (isohexane)
References
{{DEFAULTSORT:Dimethylbutane, 2,2-
Alkanes