2-Hexyne

Last updated
2-Hexyne
2-Hexyne.svg
Names
Preferred IUPAC name
Hex-2-yne
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.011.015 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 212-117-6
PubChem CID
UNII
  • InChI=1S/C6H10/c1-3-5-6-4-2/h3,5H2,1-2H3
    Key: MELUCTCJOARQQG-UHFFFAOYSA-N
  • CCCC#CC
Properties
C6H10
Molar mass 82.146 g·mol−1
Density 0.7317
Melting point −88 °C (−126 °F; 185 K) [1]
Boiling point 83.8 °C (182.8 °F; 356.9 K) [2]
1.4135
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-exclam.svg GHS-pictogram-silhouette.svg
Danger
H225, H304, H315, H319
P210, P233, P240, P241, P242, P243, P264, P280, P301+P310, P302+P352, P303+P361+P353, P305+P351+P338, P321, P331, P332+P313, P337+P313, P362, P370+P378, P403+P235, P405, P501
Related compounds
Related compounds
3-Hexyne, 1-Hexyne
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

2-Hexyne is an organic compound that belongs to the alkyne group. Just like its isomers, it also has the chemical formula of C6H10.

Reactions

2-Hexyne can be semihydrogenated to yield 2-hexene or fully hydrogenated to hexane. [3] With appropriate noble metal catalysts it can selectively form cis-2-hexene. [4]

2-Hexyne can act as a ligand on gold atoms. [5]

With strong sulfuric acid, the ketone 2-hexanone is produced. However this reaction also causes polymerization and charring. [6]

Under heat and pressure 2-hexyne polymerizes to linear oligomers and polymers. This can be hastened by some catalysts such as molybdenum pentachloride with tetraphenyl tin. However Ziegler–Natta catalysts have no action as the triple bond is hindered. [7]

Related Research Articles

<span class="mw-page-title-main">Alkene</span> Hydrocarbon compound containing one or more C=C bonds

In organic chemistry, an alkene, or olefin, is a hydrocarbon containing a carbon–carbon double bond. The double bond may be internal or in the terminal position. Terminal alkenes are also known as α-olefins.

<span class="mw-page-title-main">Hydrogenation</span> Chemical reaction between molecular hydrogen and another compound or element

Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, often an alkene. Catalysts are required for the reaction to be usable; non-catalytic hydrogenation takes place only at very high temperatures. Hydrogenation reduces double and triple bonds in hydrocarbons.

Hydroboration–oxidation reaction is a two-step hydration reaction that converts an alkene into an alcohol. The process results in the syn addition of a hydrogen and a hydroxyl group where the double bond had been. Hydroboration–oxidation is an anti-Markovnikov reaction, with the hydroxyl group attaching to the less-substituted carbon. The reaction thus provides a more stereospecific and complementary regiochemical alternative to other hydration reactions such as acid-catalyzed addition and the oxymercuration–reduction process. The reaction was first reported by Herbert C. Brown in the late 1950s and it was recognized in his receiving the Nobel Prize in Chemistry in 1979.

In organic chemistry, hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes from alkenes. This chemical reaction entails the net addition of a formyl group and a hydrogen atom to a carbon-carbon double bond. This process has undergone continuous growth since its invention: production capacity reached 6.6×106 tons in 1995. It is important because aldehydes are easily converted into many secondary products. For example, the resultant aldehydes are hydrogenated to alcohols that are converted to detergents. Hydroformylation is also used in speciality chemicals, relevant to the organic synthesis of fragrances and pharmaceuticals. The development of hydroformylation is one of the premier achievements of 20th-century industrial chemistry.

<span class="mw-page-title-main">Ene reaction</span> Reaction in organic chemistry

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<span class="mw-page-title-main">Wilkinson's catalyst</span> Chemical compound

Wilkinson's catalyst (chlorido­tris(triphenylphosphene)­rhodium(I)) is a coordination complex of rhodium with the formula [RhCl(PPh3)3], where 'Ph' denotes a phenyl group. It is a red-brown colored solid that is soluble in hydrocarbon solvents such as benzene, and more so in tetrahydrofuran or chlorinated solvents such as dichloromethane. The compound is widely used as a catalyst for hydrogenation of alkenes. It is named after chemist and Nobel laureate Sir Geoffrey Wilkinson, who first popularized its use.

<span class="mw-page-title-main">Olefin metathesis</span> Organic reaction involving the breakup and reassembly of alkene double bonds

In organic chemistry, olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often creates fewer undesired by-products and hazardous wastes than alternative organic reactions. For their elucidation of the reaction mechanism and their discovery of a variety of highly active catalysts, Yves Chauvin, Robert H. Grubbs, and Richard R. Schrock were collectively awarded the 2005 Nobel Prize in Chemistry.

In organic chemistry, hydroboration refers to the addition of a hydrogen-boron bond to certain double and triple bonds involving carbon. This chemical reaction is useful in the organic synthesis of organic compounds.

<span class="mw-page-title-main">Jacobsen epoxidation</span>

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The Milas hydroxylation is an organic reaction converting an alkene to a vicinal diol, and was developed by Nicholas A. Milas in the 1930s. The cis-diol is formed by reaction of alkenes with hydrogen peroxide and either ultraviolet light or a catalytic osmium tetroxide, vanadium pentoxide, or chromium trioxide.

In organic chemistry, the Kumada coupling is a type of cross coupling reaction, useful for generating carbon–carbon bonds by the reaction of a Grignard reagent and an organic halide. The procedure uses transition metal catalysts, typically nickel or palladium, to couple a combination of two alkyl, aryl or vinyl groups. The groups of Robert Corriu and Makoto Kumada reported the reaction independently in 1972.

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<span class="mw-page-title-main">Liebeskind–Srogl coupling</span>

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<span class="mw-page-title-main">Organocobalt chemistry</span> Chemistry of compounds with a carbon to cobalt bond

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<span class="mw-page-title-main">Lanthanocene</span>

A lanthanocene is a type of metallocene compound that contains an element from the lanthanide series. The most common lanthanocene complexes contain two cyclopentadienyl anions and an X type ligand, usually hydride or alkyl ligand.

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References

  1. Campbell, Kenneth N.; Eby, Lawrence T. (October 1941). "The Reduction of Multiple Carbon—Carbon Bonds. III. Further Studies on the Preparation of Olefins from Acetylenes 1,2". Journal of the American Chemical Society. 63 (10): 2683–2685. doi:10.1021/ja01855a050.
  2. Hennion, G. F.; Sheehan, J. J. (June 1949). "1,2-Hexadiene". Journal of the American Chemical Society. 71 (6): 1964–1966. doi:10.1021/ja01174a017.
  3. Ulan, Judith G.; Maier, Wilhelm F. (September 1989). "Mechanism of 2-hexyne hydrogenation on heterogeneous palladium". Journal of Molecular Catalysis. 54 (2): 243–261. doi:10.1016/0304-5102(89)80220-2.
  4. Schrock, Richard R.; Osborn, John A. (April 1976). "Catalytic hydrogenation using cationic rhodium complexes. II. The selective hydrogenation of alkynes to cis olefins". Journal of the American Chemical Society. 98 (8): 2143–2147. doi:10.1021/ja00424a021.
  5. Zuccaccia, Daniele; Belpassi, Leonardo; Rocchigiani, Luca; Tarantelli, Francesco; Macchioni, Alceo (5 April 2010). "A Phosphine Gold(I) π-Alkyne Complex: Tuning the Metal−Alkyne Bond Character and Counterion Position by the Choice of the Ancillary Ligand". Inorganic Chemistry. 49 (7): 3080–3082. doi:10.1021/ic100093n. PMID   20222666.
  6. Thomas, Robert J.; Campbell, Kenneth N.; Hennion, G. F. (March 1938). "Catalytic Hydration of Alkylacetylenes 1". Journal of the American Chemical Society. 60 (3): 718–720. doi:10.1021/ja01270a061.
  7. Higashimura, Toshinobu; Deng, Yun Xiang; Masuda, Toshio (March 1982). "Polymerization of 2-hexyne and higher 2-alkynes catalyzed by MoCl 5 Ph 4 Sn and WCl 6 Ph 4 Sn 1". Macromolecules. 15 (2): 234–238. Bibcode:1982MaMol..15..234H. doi:10.1021/ma00230a005.