Cyclopentene
Cyclopentene is a chemical compound with the formula (CH2)3(CH)2. It is a colorless liquid with a petrol-like odor. It has few applications, and thus is mainly used as a component of gasoline.[1] It is one of the principal cycloalkenes.
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| Preferred IUPAC name Cyclopentene | |||
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| ECHA InfoCard | 100.005.030 | ||
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| Properties | |||
| C5H8 | |||
| Molar mass | 68.11 g/mol | ||
| Density | 0.771 g/cm3 | ||
| Melting point | −135 °C (−211 °F; 138 K) | ||
| Boiling point | 44 to 46 °C (111 to 115 °F; 317 to 319 K) | ||
| Hazards | |||
| NFPA 704 (fire diamond) | |||
| Flash point | −29 °C (−20 °F; 244 K) | ||
| Related compounds | |||
| Related compounds | Cyclopentadiene Cyclobutene | ||
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |||
Production
    
Cyclopentene is produced industrially in large amounts by steam cracking of naphtha. In the laboratory, it is prepared by dehydration of cyclopentanol.[2]
It can also produced by the catalytic hydrogenation of cyclopentadiene.[3]

Use in mechanistic organic chemistry
    
Cyclopentene is used in analysing the mechanisms of organic reactions. It can be obtained from vinylcyclopropane in the vinylcyclopropane-cyclopentene rearrangement.[4]
The polymerization of cyclopentene by Ziegler-Natta catalysts yields 1,3-linkages, not the more typical 1,2-linked polymer.[5]
References
    
- Dieter Hönicke; Ringo Födisch; Peter Claus; Michael Olson (2002). "Cyclopentadiene and Cyclopentene". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a08_227.
- B. B. Corson, V. N. Ipatieff (1939). "Cyclohexylbenzene". Organic Syntheses. 19: 36. doi:10.15227/orgsyn.019.0036.
- D. Hönicke, R. Födisch, P. Claus, M. Olson: Cyclopentadiene and Cyclopentene, in: Ullmanns Enzyklopädie der Technischen Chemie 2002, Wiley-VCH, Weinheim.
- Baldwin, John E. (2003). "Thermal Rearrangements of Vinylcyclopropanes to Cyclopentenes". Chemical Reviews. 103 (4): 1197–212. doi:10.1021/cr010020z. PMID 12683781.
- Collins, Scott; Kelly, W. Mark (1992). "The microstructure of poly(cyclopentene) produced by polymerization of cyclopentene with homogeneous Ziegler-Natta catalysts". Macromolecules. 25 (1): 233–7. Bibcode:1992MaMol..25..233C. doi:10.1021/ma00027a039.
External links
    
 Media related to Cyclopentene at Wikimedia Commons Media related to Cyclopentene at Wikimedia Commons




