alkene

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alkene

(ăl`kēn), any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon double bonds (see chemical bondchemical bond,
mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the formation of an aggregate with sufficient stability to be regarded as an
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). Alkenes with only one double bond have the general formula CnH2n. In the International Union of Pure and Applied Chemistry (IUPAC) system of chemical nomenclature, the name of an alkene is derived from the name of the corresponding alkanealkane
, any of a group of aliphatic hydrocarbons whose molecules contain only single bonds (see chemical bond). Alkanes have the general chemical formula CnH2n+2.
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 by replacing the -ane alkane suffix with -ene and, if necessary, adding a prefix to indicate the location of the double bond in the molecule. The IUPAC name of the simplest alkene, H2C=CH2, is ethene, which is derived from ethane. Propene is related to propane. Two alkenes, 1-butene and 2-butene, are related to butane; these two compounds, which differ in the location of the double bond in their molecules, are structural isomersisomer
, in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of such compounds. Isomerism was first recognized by J. J. Berzelius in 1827.
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. In addition to these IUPAC names, many of the alkenes have common names, e.g., ethene is called ethylene and propene propylene. The alkenes as a group are sometimes called the ethylene series. Since the carbon-carbon double bond is sometimes called an olefinic linkage, the alkenes are sometimes called the olefins. Many of the reactions in which alkenes take part involve the cleavage of half the carbon-carbon double bond and subsequent formation of two single bonds, one to each of the adjacent carbon atoms. Such reactions include hydrogenation, with the formation of an alkane, and hydration, with the formation of an alcohol.
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alkene

[′al‚kēn]
(organic chemistry)
One of a class of unsaturated aliphatic hydrocarbons containing one or more carbon-to-carbon double bonds.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

alkene

a. any unsaturated aliphatic hydrocarbon with the general formula CnH2n
b. (as modifier): alkene series
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
In summary, efficient and simple syntheses of C-5 alkenyl and C-6 enamino ester derivatives of pipecolic acid are presented from enantiopure (R)-[alpha]-aminoadipic acid.
Investigators have developed an improved high-pressure liquid-chromatography technique for identifying and quantifying flavor precursors (alkenyl cysteine sulphoxides).
In Formula (I), [R.sup.1] and [R.sup.2] each indicate a hydrogen atom, an alkyl group having 1 to 20 carbons, an alkenyl group having 1 to 20 carbons, or an alkynyl group having 1 to 20 carbons.
Advanced analytical characterisation of sodium type (waxy / soapy) deposits showed the potential involvement of alkenyl succinic acids (like DDSA and hexadecenyl succinic acids (HDSA)) in the formation of sodium containing deposits [9].
Substituted derivatives of pyridoxine (vitamin B6) carrying alkenyl substituents at various positions of the pyridine ring represent interesting molecular structures with a rich bioactivity potential.
An alkenyl substituent (1-methylethenyl) resulted in increased antibacterial activity, as seen in limonene [1-methyl-4-(1-methylethenyl)-cydohexene], compared to an alkyl (1-methylethyl) substituent as in p-cymene [l-methyl-4-(1-methylethyl)-benzene].
BASF has obtained a patent for a n aqueous coating formulation comprised of a substituted, branched polyethyleneimine, which is obtained by a process comprised of reacting a branched polyethyleneimine having a weight-average molecular weight of from 500 to 10,000 g/mol with a carboxylic acid derivative of formula (I) R--(C=0)X (I), wherein R is a C5 to C18 alkyl group or a C5 to C18 alkenyl group, X is a halogen, a hydroxyl group, or a group R--(C=0)--O--, a molar amount of the carboxylic acid derivative in the reacting is from 3 to 10 mol percent of a molar amount of ethyleneimine employed in preparing the branched polyethyleneimine, the reacting is comprised of formation and removal of a byproduct HX, and the formulation is configured to coat a substrate that is comprised of tannin.
Further investigations towards other 2-([alpha]-hydroxyl alkyl) piperidine analogues and indolizidines by introduction of various alkenyl substituents in the Barbier allylation are in progress.
The bands in the regions 1600-1400 [cm.sup.-1] are ascribed to the stretching mode of terpyridine and the alkenyl groups.
Yasukohchi, "Polyoxyalkylene alkenyl ether-maleic ester copolymer and use thereof," US Patent 5142036, 1989.