Alkenes

thumb|right|120px|A 3D model of ethylene, the simplest alkene

Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon–carbon double bonds).

Propylene, also known as propene, is an unsaturated organic compound with the chemical formula . It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petroleum-like odor.

Butene, also known as butylene, is an alkene with the formula . The word butene may refer to any of the individual compounds. They are colourless gases that are present in crude oil as a minor constituent in quantities that are too small for viable extraction. Butene is therefore obtained by catalytic cracking of long-chain hydrocarbons left during refining of crude oil. Cracking produces a mixture of products, and the butene is extracted from this mixture by fractional distillation.

Isobutylene (or 2-methylpropene) is a hydrocarbon with the chemical formula . It is a four-carbon branched alkene (olefin), one of the four isomers of butylene. It is a colorless flammable gas, and is of considerable industrial value.

Pentenes are alkenes with the chemical formula . Each molecule contains one double bond within its molecular structure. Six different compounds are in this class, differing from each other by whether the carbon atoms are attached linearly or in a branched structure and whether the double bond has a cis or trans form.

Decene is an organic compound with the chemical formula . Decene contains a chain of ten carbon atoms with one double bond, making it an alkene. There are many isomers of decene depending on the position and geometry of the double bond. Dec-1-ene is the only isomer of industrial importance. As an alpha olefin, it is used as a comonomer in copolymers and is an intermediate in the production of epoxides, amines, oxo alcohols, synthetic lubricants, synthetic fatty acids and alkylated aromatics.

In organic chemistry, hexene is a hydrocarbon with the chemical formula . The prefix "hex" is derived from the fact that there are 6 carbon atoms in the molecule, while the "-ene" suffix denotes that there is an alkene present—two carbon atoms are connected via a double bond. There are several isomers of hexene, depending on the position and geometry of the double bond in the chain. One of the most common industrially useful isomers is 1-hexene, an alpha-olefin. Hexene is used as a comonomer in the production of polyethylene.

1-Butene (IUPAC name: But-1-ene, also known as 1-butylene) is the organic compound with the formula CH3CH2CH=CH2. It is a colorless gas, but easily condensed to give a colorless liquid. It is classified as a linear alpha-olefin (terminal alkene). It is one of the isomers of butene (butylene). It is a precursor to diverse products.

1-Heptene is an organic compound with the formula . It is the terminal "linear" C7 alkene. A colorless volatile liquid, it is produced as one of myriad products by the Fischer-Tropsch Process. It is used to prepare 1-octene, a common comonomer. It is classified as higher olefin, or alkene with the formula C7H14.

1-Hexene (hex-1-ene) is an organic compound with the formula C6H12. It is an alkene that is classified in industry as higher olefin and an alpha-olefin, the latter term meaning that the double bond is located at the alpha (primary) position, endowing the compound with higher reactivity and thus useful chemical properties. 1-Hexene is an industrially significant linear alpha olefin. It is a colourless liquid.

2-Methyl-2-butene, 2m2b, 2-methylbut-2-ene, beta-isoamylene, or trimethylethylene is an alkene hydrocarbon with the molecular formula C5H10. It is a flammable liquid.

1-Nonene is particular structural isomer of nonene where the double bond is located at the primary, or alpha, position making it a linear alpha olefin. It is used in the production of surfactants and lubricants, usually by way of nonylphenol. Its more branched analogue, tripropylene, is also used in this way.

2-Butene is an acyclic alkene with four carbon atoms. It is the simplest alkene exhibiting cis/trans-isomerism (also known as (E/Z)-isomerism); that is, it exists as two geometric isomers cis-2-butene ((Z)-but-2-ene) and trans-2-butene ((E)-but-2-ene).

1-Octene is an organic compound with a formula CH2CHC6H13. The alkene is classified as a higher olefin and alpha-olefin, meaning that the double bond is located at the alpha (primary) position, endowing this compound with higher reactivity and thus useful chemical properties. 1-Octene is one of the important linear alpha olefins in industry. It is a colourless liquid.

thumb|300px|right|1-octene Octene is an alkene with the formula C8H16|. Several isomers of octene are known, depending on the position and the geometry of the double bond in the carbon chain.

Nonene is an alkene with the molecular formula C9H18. Many structural isomers are possible, depending on the location of the C=C double bond and the branching of the other parts of the molecule. Industrially, the most important nonenes are trimers of propene: Tripropylene. This mixture of branched nonenes is used in the alkylation of phenol to produce nonylphenol, a precursor to detergents, which are also controversial pollutants.

thumb|right|The structure of a conjugated enyne

Neohexene is the hydrocarbon compound with the chemical formula . It is a colorless liquid, with properties similar to other hexenes. It is a precursor to commercial synthetic musk perfumes.

1-Octadecene is a long-chain hydrocarbon and an alkene with the molecular formula CH2=CH(CH2)15CH3. It is one of many isomers of octadecene. Classified as an alpha-olefin, 1-octadecene is the longest alkene that is liquid at room temperature.

1-Dodecene is an alkene with the formula C10H21CH=CH2, consisting of a chain of twelve carbon atoms ending with a double bond. While there are many isomers of dodecene depending on which carbon the double bond is placed, this isomer is of greater commercial importance. It is classified as an alpha-olefin. Alpha-olefins are distinguished by having a double bond at the primary or alpha (α) position. This location of a double bond enhances the reactivity of the compound and makes it useful for a number of applications, especially for the production of detergents.

class of chemical compounds

'(Z)-9-Tricosene, known as muscalure', is an insect pheromone found in dipteran flies such as the housefly. Females produce it to attract males to mate. It is used as a pesticide, as in Maxforce Quickbayt by Bayer, luring males to traps to prevent them from reproducing.

4-Methyl-1-pentene is used as a monomer for olefin polymerisation. The resulting polymer is poly(4-methyl-1-pentene).

Petrochemical process to break down saturated hydrocarbons in smaller molecules

Tripropylene, also known as propylene trimer, is usually sold as a mixture of structural isomers of nonene. This mixture is obtained by oligomerization of propene: 3 C3H6 → C9H18 In this process, two double bonds are lost and one is retained as illustrated by the isomer shown in the figure. The reaction is catalyzed by acids, such as polyphosphoric acid. A variety of catalysts have been explored. The reaction proceeds via the formation of a carbocation ((CH3)2CH+), which attacks another propylene unit, generating a new carbocation, etc. This kind of process affords mixtures (C3H6)n.

1-Hexadecene, also known as 1-cetene, is a long-chain hydrocarbon and an alkene with the molecular formula CH2=CH(CH2)13CH3. It is one of many isomers of hexadecene. Classified as an alpha-olefin, 1-hexadecene is a colorless liquid.

functional group

'Tetra-tert-butylethylene' is a hypothetical organic compound, a hydrocarbon with formula C18H36, or ((H3C−)3C−)2C=C(−C(−CH3)3)2. As the name indicates, its molecular structure can be viewed as an ethylene molecule H2C=CH2 with the four hydrogens replaced by tert-butyl −C(−CH3)3 groups.

Tetramethylethylene is a hydrocarbon with the formula Me2C=CMe2 (Me = methyl). A colorless liquid, it is the simplest tetrasubstituted alkene.

organic chemical reaction

Chemical reaction

Tetravinylmethane is an organic compound with formula C9H12, consisting of four vinyl groups bonded to a central carbon atom. It has been synthesised by several different routes.