Aliphatic compound

File:Butane-2D-flat.png

Acyclic aliphatic compound (Butane)

File:Cyclobutane2.svg

Cyclic aliphatic compound (Cyclobutane)

In organic chemistry, aliphatic compounds (11px /ˌælɨˈfætɨk/; G. aleiphar, fat, oil) are acyclic or cyclic, non-aromatic carbon compounds. Thus, aliphatic compounds are opposite to aromatic compounds.

Structure

In aliphatic compounds, carbon atoms can be joined together in straight chains, branched chains, or non-aromatic rings (in which case they are called alicyclic). Aliphatic compounds can be saturated, joined by single bonds (alkanes), or unsaturated, with double bonds (alkenes) or triple bonds (alkynes). Besides hydrogen, other elements can be bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine.

The simplest aliphatic compound is methane (CH₄). Aliphatics include alkanes (e.g. paraffin hydrocarbons), alkenes (e.g. ethylene) and alkynes (e.g. acetylene). Fatty acids consist of an unbranched aliphatic tail attached to a carboxyl group.

Properties

Most aliphatic compounds are flammable, allowing the use of hydrocarbons as fuel, such as methane in Bunsen burners and as Liquified Natural Gas (LNG), and acetylene in welding.

Examples for aliphatic compounds

The most important group of aliphatic compounds are:

• n-, Iso- and Cyclo-Alkanes (Saturated Hydrocarbons)
• n-, Iso- and Cyclo-Alkenes and -Alkynes (Unsaturated Hydrocarbons).

Important examples of low-molecular aliphatic compounds can be found in the list below (sorted by the number of carbon-atoms):

Formula	Name	CAS-Number	Structural Formula	Chemical Classification
CH4	Methane	74-82-8	75px	Alkane
C2H2	Ethyne	74-86-2	75px	Alkyne
C2H4	Ethene	74-85-1	75px	Alkene
C2H6	Ethane	74-84-0	75px	Alkane
C3H4	Propyne	74-99-7	75px	Alkyne
C3H6	Propene	-	100px	Alkene
C3H8	Propane	-	100px	Alkane
C4H6	1,2-Butadiene	590-19-2	100px	Diene
C4H6	1-Butyne	-	100px	Alkyne
C4H8	Butene	-	e.g. 100px	Alkene
C4H10	Butane	-	100px	Alkane
C6H10	Cyclohexene	110-83-8	40px	Cycloalkene
C5H12	n-pentane	109-66-0	75px	Alkane
C7H14	Cycloheptane	291-64-5	50px	Cycloalkane
C7H14	Methylcyclohexane	108-87-2	75px	Cyclohexane
C8H8	Cubane	277-10-1	75px	Cyclobutane
C9H20	Nonane	111-84-2	100px	Alkane
C10H12	Dicyclopentadiene	77-73-6	125px	Diene, Cycloalkene
C10H16	Phellandrene	99-83-2	50px50px	Terpene, Diene Cycloalkene
C10H16	α-Terpinene	99-86-5	30px	Terpene, Cycloalkene, Diene
C10H16	Limonene	5989-27-5	50px50px	Terpene, Diene, Cycloalkene
C11H24	Undecane	1120-21-4	125px	Alkane
C30H50	Squalene	111-02-4	125px	Terpene, Polyene
C2nH4n	Polyethylene	9002-88-4	75px	Alkane

Aliphatic acids

Aliphatic acids are the acids of nonaromatic hydrocarbons, such as acetic, propionic, and butyric acids.

See also

• Aromatic compound

References

ar:مركب أليفاتي