Cyclohexene

<h2 id="production-and-uses">Production and uses</h2>
<p>Cyclohexene is produced by the partial <a href="/facts/Hydrogenation/l7EzNSA7">hydrogenation</a> of <a href="/facts/Benzene/Fguue7nr">benzene</a>, a process developed by the <a href="/facts/Asahi_Chemical/6suGrYpQ">Asahi Chemical</a> company.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a>  The main product of the process is cyclohexane because cyclohexene is more easily hydrogenated than benzene.
</p><p>In the laboratory, it can be prepared by <a href="/facts/Dehydration_reaction/dTAxlyRX">dehydration</a> of <a href="/facts/Cyclohexanol/kHdlHrys">cyclohexanol</a>.<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a>
</p>
C6H11OH   →   C6H10  +  H2O
<h2 id="reactions-and-uses">Reactions and uses</h2>
<p>Benzene is converted to <a href="/facts/Cyclohexylbenzene/9YUyuJyF">cyclohexylbenzene</a> by acid-catalyzed alkylation with cyclohexene.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a> Cyclohexylbenzene is a precursor to both phenol and cyclohexanone.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a>
</p><p>Hydration of cyclohexene gives <a href="/facts/Cyclohexanol/kHdlHrys">cyclohexanol</a>, which can be <a href="/facts/Dehydrogenation/vwFAAqzp">dehydrogenated</a> to give <a href="/facts/Cyclohexanone/Hf3YTWjB">cyclohexanone</a>, a precursor to <a href="/facts/Caprolactam/tT28x3tx">caprolactam</a>.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a>
</p><p>The <a href="/facts/Oxidative_cleavage/6DdmXG4S">oxidative cleavage</a> of cyclohexene gives <a href="/facts/Adipic_acid/8l8ahlDC">adipic acid</a>. <a href="/facts/Hydrogen_peroxide/vju6HBIc">Hydrogen peroxide</a> is used as the oxidant in the presence of a tungsten catalyst.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> 
</p><p><a href="/facts/1%2c5-Hexadiene/hVSK9zrd">1,5-Hexadiene</a> is produced by <a href="/facts/Ethenolysis/0xMs2ea1">ethenolysis</a> of cyclohexene. Bromination gives 1,2-dibromocyclohexane.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a>
</p>
<h2 id="structure">Structure</h2>
<p>Cyclohexene is most stable in a half-chair <a href="/facts/Conformational_isomerism/JflrT5Ws">conformation</a>,<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> unlike the preference for a chair form of <a href="/facts/Cyclohexane/FDAW5j8v">cyclohexane</a>. One basis for the <a href="/facts/Cyclohexane_conformation/1wI7q3kW">cyclohexane conformational</a> preference for a chair is that it allows each bond of the ring to adopt a <a href="/facts/Staggered_conformation/EYoNI8Pv">staggered conformation</a>. For cyclohexene, however, the alkene is planar, equivalent to an eclipsed conformation at that bond.
</p>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Diels-Alder_reaction/zc6dVpKl">Diels-Alder reaction</a></li>
<li><a href="/facts/Cyclohexa-1%2c3-diene/53eNrh1p">Cyclohexa-1,3-diene</a></li>
<li><a href="/facts/Cyclohexa-1%2c4-diene/whu31FNg">Cyclohexa-1,4-diene</a></li></ul>

<h2 id="external-links">External links</h2>
<ul><li><a href="https://www.ilo.org/dyn/icsc/showcard.display?p_lang=en&p_card_id=1054&p_version=2">International Chemical Safety Card 1054</a></li>
<li>NIOSH Pocket Guide to Chemical Hazards. <a href="https://www.cdc.gov/niosh/npg/npgd0167.html">"#0167"</a>. <a href="/facts/National_Institute_for_Occupational_Safety_and_Health/5WjdDNMN">National Institute for Occupational Safety and Health</a> (NIOSH).</li>
<li><a href="https://web.archive.org/web/20120328181429/http://hazard.com/msds/mf/baker/baker/files/c7073.htm">Material Safety Data Sheet for cyclohexene</a></li>
<li><a href="https://web.archive.org/web/20071022034608/http://physchem.ox.ac.uk/MSDS/CY/cyclohexene.html">Safety MSDS data</a></li>
<li><a href="https://web.archive.org/web/20070503012733/http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/D-Addit_ar-e.htm">Reaction of Cyclohexene with Bromine and Potassium Permanganate</a></li>
<li><a href="http://www.orgsyn.org/orgsyn/prep.asp?prep=cv1p0183">Cyclohexene synthesis</a></li>
<li><a href="http://www.inchem.org/documents/sids/sids/110838.pdf">Data sheet at inchem.org</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Xie, Feng; Chen, Lihang; Cedeño Morales, Eder Moisés; Ullah, Saif; Fu, Yiwen; Thonhauser, Timo; Tan, Kui; Bao, Zongbi; Li, Jing (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. Bibcode:2024NatCo..15.2240X. doi:10.1038/s41467-024-46556-6. PMC 10933443. PMID 38472202. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10933443" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10933443</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>US 9771313, Narisawa, Naoki & Tanaka, Katsutoshi, "Cyclohexanol, method for producing cyclohexanol, and method for producing adipic acid", published 26 Sep 2017
 <a href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US9771313" target="_blank">https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US9771313</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>G. H. Coleman, H. F. Johnstone (1925). "Cyclohexene". Organic Syntheses. 5: 33. doi:10.15227/orgsyn.005.0033. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>B. B. Corson, V. N. Ipatieff (1939). "Cyclohexylbenzene". Organic Syntheses. 19: 36. doi:10.15227/orgsyn.019.0036. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
<li id="fn:5"><p>Plotkin, Jeffrey S. (2016-03-21). "What's New in Phenol Production?". American Chemical Society. Archived from the original on 2019-10-27. Retrieved 2018-01-02. <a href="https://web.archive.org/web/20191027122212/https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html" target="_blank">https://web.archive.org/web/20191027122212/https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li>
<li id="fn:6"><p>Musser, Michael T. (2005). "Cyclohexanol and Cyclohexanone". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a08_217. ISBN 978-3-527-30673-2. <a href="978-3-527-30673-2" target="_blank">978-3-527-30673-2</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li>
<li id="fn:7"><p>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. Bibcode:2000JChEd..77.1627R. doi:10.1021/ed077p1627. <a href="/wiki/Bibcode_(identifier)" target="_blank">/wiki/Bibcode_(identifier)</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li>
<li id="fn:8"><p>H. R. Snyder, L. A. Brooks (1932). "1,2-Dibromocyclohexane". Organic Syntheses. 12: 26. doi:10.15227/orgsyn.012.0026. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li>
<li id="fn:9"><p>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. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li>
</ol>

Cyclohexene open-in-new

Cyclohexene