Cyclohexene Explained

Cyclohexene is a hydrocarbon with the formula . It is an example of a cycloalkene. At room temperature, cyclohexene is a colorless liquid with a sharp odor. It has few practical applications.

Production and uses

Cyclohexene is produced by the partial hydrogenation of benzene, a process developed by the Asahi Chemical company.[1] The main product of the process is cyclohexane because cyclohexene is more easily hydrogenated than benzene.

In the laboratory, it can be prepared by dehydration of cyclohexanol.[2]

Reactions and uses

Benzene is converted to cyclohexylbenzene by acid-catalyzed alkylation with cyclohexene.[3] Cyclohexylbenzene is a precursor to both phenol and cyclohexanone.[4]

Hydration of cyclohexene gives cyclohexanol, which can be dehydrogenated to give cyclohexanone, a precursor to caprolactam.

The oxidative cleavage of cyclohexene gives adipic acid. Hydrogen peroxide is used as the oxidant in the presence of a tungsten catalyst.[5]

Bromination gives 1,2-dibromocyclohexane.[6]

Structure

Cyclohexene is most stable in a half-chair conformation,[7] unlike the preference for a chair form of cyclohexane. One basis for the cyclohexane conformational preference for a chair is that it allows each bond of the ring to adopt a staggered conformation. For cyclohexene, however, the alkene is planar, equivalent to an eclipsed conformation at that bond.

See also

External links

Notes and References

  1. Cyclohexanol, method for producing cyclohexanol, and method for producing adipic acid. 26 Sep 2017. Narisawa. Tanaka. Naoki. Katsutoshi. US. 9771313.
  2. 10.15227/orgsyn.005.0033. Cyclohexene. Organic Syntheses. 1925. 5. 33. G. H. Coleman, H. F. Johnstone.
  3. 10.15227/orgsyn.019.0036. Cyclohexylbenzene. Organic Syntheses. 1939. 19. 36. B. B. Corson, V. N. Ipatieff.
  4. Web site: What's New in Phenol Production? . Plotkin . Jeffrey S. . American Chemical Society . 2016-03-21 . 2018-01-02 . https://web.archive.org/web/20191027122212/https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html . 2019-10-27 . dead .
  5. Green Chemistry in the Organic Teaching Laboratory: An Environmentally Benign Synthesis of Adipic Acid . Scott M. . Reed . James E. . Hutchison . J. Chem. Educ. . 2000 . 77 . 12 . 1627–1629 . 10.1021/ed077p1627. 2000JChEd..77.1627R .
  6. 10.15227/orgsyn.012.0026. 1,2-Dibromocyclohexane. Organic Syntheses. 1932. 12. 26. H. R. Snyder, L. A. Brooks.
  7. Conformational preferences and interconversion barriers in cyclohexene and derivatives . Frederick R. . Jensen . C. Hackett . Bushweller . J. Am. Chem. Soc. . 1969 . 91 . 21 . 5774–5782 . 10.1021/ja01049a013.