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 minor component of gasoline, present in concentrations of less than 1%. It is one of the principal cycloalkenes.
History and synthesis
Cyclopentene was first prepared by Carl Gärtner in 1893 from iodocyclopentane with potassium hydroxide. He named it pentamethenylene (German: Pentamethenylen).3
Cyclopentene is produced industrially in large amounts by steam cracking of naphtha. In the laboratory, it is prepared by dehydration of cyclopentanol.4 Substituted cyclopentenes are the product of the vinylcyclopropane-cyclopentene rearrangement.5
It can also be produced by the catalytic hydrogenation of cyclopentadiene.6
Reactions
The polymerization of cyclopentene by Ziegler-Natta catalysts yields 1,3-linkages, not the more typical 1,2-linked polymer.7
Palladium-catalyzed hydrocarboxylation of cyclopentene gives cyclopentanecarboxylic acid:8
C5H8 + CO + H2O → C5H9CO2HExternal links
- Media related to Cyclopentene at Wikimedia Commons
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. ISBN 978-3-527-30673-2. 978-3-527-30673-2 ↩
"Hydrocarbon Composition of Gasoline Vapor Emissions from Enclosed Fuel Tanks". nepis.epa.gov. United States Environmental Protection Agency. 2011. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100GPED.TXT ↩
Gärtner, Carl (January 1893). "Das Pentamethenylen und sein Dibromür". Justus Liebigs Annalen der Chemie. 275 (2–3): 331–332. doi:10.1002/jlac.18932750217. ISSN 0075-4617. https://books.google.com/books?id=QpEBhiH9p4QC&pg=PA331 ↩
B. B. Corson, V. N. Ipatieff (1939). "Cyclohexylbenzene". Organic Syntheses. 19: 36. doi:10.15227/orgsyn.019.0036. /wiki/Doi_(identifier) ↩
Baldwin, John E. (2003). "Thermal Rearrangements of Vinylcyclopropanes to Cyclopentenes". Chemical Reviews. 103 (4): 1197–212. doi:10.1021/cr010020z. PMID 12683781. /wiki/Doi_(identifier) ↩
D. Hönicke, R. Födisch, P. Claus, M. Olson: Cyclopentadiene and Cyclopentene, in: Ullmanns Enzyklopädie der Technischen Chemie 2002, Wiley-VCH, Weinheim. /wiki/Ullmann%27s_Encyclopedia_of_Industrial_Chemistry ↩
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. /wiki/Bibcode_(identifier) ↩
Sang, Rui; Kucmierczyk, Peter; Dühren, Ricarda; Razzaq, Rauf; Dong, Kaiwu; Liu, Jie; Franke, Robert; Jackstell, Ralf; Beller, Matthias (2019). "Synthesis of Carboxylic Acids by Palladium‐Catalyzed Hydroxycarbonylation". Angewandte Chemie International Edition. 58 (40): 14365–14373. doi:10.1002/anie.201908451. PMID 31390131. S2CID 199466915. https://doi.org/10.1002%2Fanie.201908451 ↩