Chemistry:Cyclohexene
Cyclohexene is a hydrocarbon with the formula (CH
2)
4C
2H
2. It is a cycloalkene. At room temperature, cyclohexene is a colorless liquid with a sharp odor. Among its uses, it is an intermediate in the commercial synthesis of nylon.[1]
Production and uses
Cyclohexene is produced by the partial hydrogenation of benzene, a process developed by the Asahi Chemical company.[2] 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.[3]
- C
6H
11OH → C
6H
10 + H
2O
Reactions and uses
Benzene is converted to cyclohexylbenzene by acid-catalyzed alkylation with cyclohexene.[4] Cyclohexylbenzene is a precursor to both phenol and cyclohexanone.[5]
Hydration of cyclohexene gives cyclohexanol, which can be dehydrogenated to give cyclohexanone, a precursor to caprolactam.[6]
The oxidative cleavage of cyclohexene gives adipic acid. Hydrogen peroxide is used as the oxidant in the presence of a tungsten catalyst.[7]
1,5-Octadiene is produced by ethenolysis of cyclohexene.[8] Bromination gives 1,2-dibromocyclohexane.[9]
Structure
Cyclohexene is most stable in a half-chair conformation,[10] 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
- Diels-Alder reaction
- Cyclohexa-1,3-diene
- Cyclohexa-1,4-diene
References
- ↑ Xie, Feng; Chen, Lihang; Cedeño Morales, Eder Moisés; Ullah, Saif; Fu, Yiwen; Thonhauser, Timo; Tan, Kui; Bao, Zongbi et al. (2024). "Complete separation of benzene-cyclohexene-cyclohexane mixtures via temperature-dependent molecular sieving by a flexible chain-like coordination polymer". Nature Communications 15 (1): 2240. doi:10.1038/s41467-024-46556-6. PMID 38472202. Bibcode: 2024NatCo..15.2240X.
- ↑ Narisawa, Naoki & Katsutoshi Tanaka, "Cyclohexanol, method for producing cyclohexanol, and method for producing adipic acid", US patent 9771313, published 26 Sep 2017
- ↑ G. H. Coleman, H. F. Johnstone (1925). "Cyclohexene". Organic Syntheses 5: 33. doi:10.15227/orgsyn.005.0033.
- ↑ B. B. Corson, V. N. Ipatieff (1939). "Cyclohexylbenzene". Organic Syntheses 19: 36. doi:10.15227/orgsyn.019.0036.
- ↑ Plotkin, Jeffrey S. (2016-03-21). "What's New in Phenol Production?". American Chemical Society. https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html.
- ↑ Musser, Michael T. (2005). "Ullmann's Encyclopedia of Industrial Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a08_217.
- ↑ Reed, Scott M.; Hutchison, James E. (2000). "Green Chemistry in the Organic Teaching Laboratory: An Environmentally Benign Synthesis of Adipic Acid". J. Chem. Educ. 77 (12): 1627–1629. doi:10.1021/ed077p1627. Bibcode: 2000JChEd..77.1627R.
- ↑ Kustov, L. M.; Furman, D. B. (2018-07-15). "Catalytic synthesis of octadiene-1,7 from ethylene and cyclohexene". Journal of Organometallic Chemistry. Special Issue dedicated to Prof. Irina Beletskaya 867: 261–265. doi:10.1016/j.jorganchem.2018.01.059. ISSN 0022-328X. https://www.sciencedirect.com/science/article/pii/S0022328X18300779.
- ↑ H. R. Snyder, L. A. Brooks (1932). "1,2-Dibromocyclohexane". Organic Syntheses 12: 26. doi:10.15227/orgsyn.012.0026.
- ↑ Jensen, Frederick R.; Bushweller, C. Hackett (1969). "Conformational preferences and interconversion barriers in cyclohexene and derivatives". J. Am. Chem. Soc. 91 (21): 5774–5782. doi:10.1021/ja01049a013.
External links
- International Chemical Safety Card 1054
- NIOSH Pocket Guide to Chemical Hazards. "#0167". National Institute for Occupational Safety and Health (NIOSH). https://www.cdc.gov/niosh/npg/npgd0167.html.
- Material Safety Data Sheet for cyclohexene
- Safety MSDS data
- Reaction of Cyclohexene with Bromine and Potassium Permanganate
- Cyclohexene synthesis
- Data sheet at inchem.org
