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	{{chembox		{{chembox
	| Watchedfields = changed		|Watchedfields = changed
	| verifiedrevid = 402497210		|verifiedrevid = 434527108
	| ImageFileL1_Ref = {{chemboximage|correct|??}}		|ImageFileL1_Ref = {{chemboximage|correct|??}}
	| ImageFileL1=Methylcyclohexane-2D-skeletal.png		|ImageFileL1=Methylcyclohexane-2D-skeletal.png
			|ImageFileR1=Methylcyclohexane-3D-balls.png
	| ImageSizeL1=120px
	| ImageFileR1=Methylcyclohexane-3D-balls.png		|PIN=Methylcyclohexane
			|OtherNames=Hexahydrotoluene<br />Cyclohexylmethane<br />Toluene hexahydride
	| ImageSizeR1=130px
			|Section1={{Chembox Identifiers
	| IUPACName=methylcyclohexane
			|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
	| OtherNames=Hexahydrotoluene<br />Cyclohexylmethane<br />Toluene hexahydride
			|ChemSpiderID = 7674
	| Section1= {{Chembox Identifiers
			|ChEBI = 165745
	| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
			|InChI = 1/C7H14/c1-7-5-3-2-4-6-7/h7H,2-6H2,1H3
	| ChemSpiderID = 7674
			|InChIKey = UAEPNZWRGJTJPN-UHFFFAOYAG
	| InChI = 1/C7H14/c1-7-5-3-2-4-6-7/h7H,2-6H2,1H3
			|StdInChI_Ref = {{stdinchicite|correct|chemspider}}
	| InChIKey = UAEPNZWRGJTJPN-UHFFFAOYAG
			|StdInChI = 1S/C7H14/c1-7-5-3-2-4-6-7/h7H,2-6H2,1H3
	| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
			|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
	| StdInChI = 1S/C7H14/c1-7-5-3-2-4-6-7/h7H,2-6H2,1H3
			|StdInChIKey = UAEPNZWRGJTJPN-UHFFFAOYSA-N
	| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
			|CASNo_Ref = {{cascite|correct|CAS}}
	| StdInChIKey = UAEPNZWRGJTJPN-UHFFFAOYSA-N
			|CASNo=108-87-2
	| CASNo_Ref = {{cascite|correct|CAS}}
			|UNII_Ref = {{fdacite|correct|FDA}}
	| CASNo=108-87-2
			|UNII = H5WXT3SV31
	| PubChem=7962
			|PubChem=7962
	| SMILES=CC1CCCCC1
			|SMILES=CC1CCCCC1
	}}
			}}
	|Section2= {{Chembox Properties
			|Section2={{Chembox Properties
	| Formula=C<sub>7</sub>H<sub>14</sub>
			|C=7 | H=14
	| MolarMass=98.186 g/mol
	| Appearance=colorless liquid		|Appearance=Colourless liquid
			|Odor = faint, ]-like<ref name=PGCH/>
	| Density=0.77 g/cm<sup>3</sup>
			|Density=0.77 g/cm<sup>3</sup>
	| MeltingPt = -126.3 °C, 146.9 K
			|MeltingPtC = -126.3
	| BoilingPt = 101 °C, 374 K
			|BoilingPtC = 101
	| Solubility=insoluble in water
			|Solubility=0.014 g/L at 25 °C<ref name="sigma" />
	}}
			|VaporPressure = 37 mmHg (20°C)<ref name=PGCH/><BR/>
	|Section3= {{Chembox Hazards
			49.3 hPa at 20.0 °C<BR/>
	| NFPA-F = 3 | NFPA-H = 1 | NFPA-R = 0 | NFPA-O =
			110.9 hPa at 37.7 °C<ref name="sigma" />
	| MainHazards=severe fire hazard
			|MagSus = -78.91·10<sup>−6</sup> cm<sup>3</sup>/mol
	| FlashPt=-3 °C, 270 K
			}}
	| Autoignition=
			|Section3={{Chembox Hazards
	}}
			|ExternalSDS = <ref name="sigma">{{Sigma-Aldrich|Sial|id=300306|name=Methylcyclohexane|accessdate=2022-03-17}}</ref>
			|GHSSignalWord = Danger
			|GHSPictograms = {{GHS02}}{{GHS07}}{{GHS08}}{{GHS09}}
			|HPhrases = {{H-phrases|225|302|304|315|336|410}}<ref name="sigma" />
			|PPhrases = {{P-phrases|210|235|301+310|331|370+378|403}}<ref name="sigma" />
			|NFPA-F = 3 | NFPA-H = 1 | NFPA-R = 0 | NFPA-S =
			|MainHazards=severe fire hazard
			|FlashPtC = -4
			|FlashPt_notes =Closed cup
			|FlashPt_ref =<ref name="sigma" />
			|AutoignitionPtC =283
			|AutoignitionPt_ref=<ref name="sigma" />
			|ExploLimits = 1.2%-6.7%<ref name=PGCH/><ref name="sigma" />
			|PEL = TWA 500 ppm (2000 mg/m<sup>3</sup>)<ref name=PGCH>{{PGCH|0406}}</ref>
			|REL = TWA 400 ppm (1600 mg/m<sup>3</sup>)<ref name=PGCH/>
			|IDLH = 1200 ppm<ref name=PGCH/>
			|LC50 = 10172 ppm (mouse, 2 hr)<br/>10,000-12,500 ppm (mouse, 2 hr)<br/>15227 ppm (rabbit, 1 hr)<ref name=IDLH>{{IDLH|108872| Methylcyclohexane}}</ref>
			|LD50 = 2250 mg/kg (mouse, oral)<ref name=IDLH/>
			}}
	}}		}}
	'''Methylcyclohexane''' is a colourless ] with a faint ]-like odour. Its molecular formula is C<sub>7</sub>H<sub>14</sub>. Methylcyclohexane is used in ] and as a ] for ] ethers. It is a component of ] and is also a component of correction fluids.		'''Methylcyclohexane''' (cyclohexylmethane) is an ] with the molecular formula is CH<sub>3</sub>C<sub>6</sub>H<sub>11</sub>. Classified as ], it is a colourless ] with a faint odor.
			Methylcyclohexane is used as a ]. It is mainly converted in naphtha ]s to ].<ref name="Ullmann">M. Larry Campbell. "Cyclohexane" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2012. {{doi|10.1002/14356007.a08_209.pub2}}</ref> A special use is in PF-1 priming fluid in ] to aid engine start-up when they run on special nonvolatile jet fuel like ].<ref name=":1">{{Cite book |last=Martel |first=Charles R. |url=https://books.google.com/books?id=sSCc6U-5u-MC&pg=PA10 |title=Military Jet Fuels, 1944-1987 |date=1987 |publisher=Aero Propulsion Laboratory, Air Force Wright Aeronautical Laboratories, Air Force Systems Command, United States Air Force |pages=10 |language=en}}</ref> Methylcyclohexane is also used in some ] (such as White-Out) as a solvent.
			== History ==
			While researching ] of ] with ] in 1876<ref>{{Cite web |title=Феликс Романович Вреден - Биография |url=https://physchem.chimfak.sfedu.ru/Source/History/Persones/Wreden.html |access-date=2024-12-03 |website=physchem.chimfak.sfedu.ru |language=ru}}</ref> as part of his doctoral dissertation,<ref>{{Cite book |url=https://rusneb.ru/catalog/000200_000018_v19_rc_1542148/ |title=О гидрогенизации монобензоловых углеводородов О продуктах гидрогенизации и о строении нафталина - Соч. Ф. Вредена |date=1876 |language=ru}}</ref> {{Ill|Felix Wreden|ru|Вреден, Феликс Романович}} first prepared the hydrocarbon from toluene. He determined its boiling point to be 97°C, its density at 20°C to by 0.76 g/cc and named it '''hexahydrotoluene'''.<ref>{{Cite journal |last=Wreden |first=F. |date=1877 |title=Ueber die Hydrogenisation des Benzols und seiner Homologen |url=https://books.google.com/books?id=SubzWeF2UHsC&pg=PA161 |journal=Justus Liebigs Annalen der Chemie |language=de |volume=187 |issue=2-3 |pages=153–167 |doi=10.1002/jlac.18771870202 |issn=1099-0690}}</ref> It was soon identified in oil from ] and obtained by other synthetic methods.<ref>{{Cite book |last=Richter |first=Victor von |url=https://books.google.com/books?id=HYQyAQAAMAAJ&pg=PA292 |title=Victor Von Richter's Organic Chemistry: Or, Chemistry of the Carbon Compounds |date=1899 |publisher=P. Blakiston's son & Company |pages=292 |language=en}}</ref>
			==Production and use==
			Most methylcyclohexane is extracted from petroleum but it can be also produced by catalytic hydrogenation of toluene:
			:CH<sub>3</sub>C<sub>6</sub>H<sub>5</sub> + 3 H<sub>2</sub> → CH<sub>3</sub>C<sub>6</sub>H<sub>11</sub>
			The hydrocarbon is a minor component of automobile fuel, with its share in US ] varying between 0.3 and 1.7% in early 1990s<ref>{{Cite journal |last=Doskey |first=Paul V. |last2=Porter |first2=Joseph A. |last3=Scheff |first3=Peter A. |date=November 1992 |title=Source Fingerprints for Volatile Non-Methane Hydrocarbons |url=https://www.tandfonline.com/doi/full/10.1080/10473289.1992.10467090 |journal=Journal of the Air & Waste Management Association |language=en |volume=42 |issue=11 |pages=1437–1445 |doi=10.1080/10473289.1992.10467090 |issn=1047-3289}}</ref> and 0.1 to 1% in 2011.<ref>{{cite web |date=2011 |title=Hydrocarbon Composition of Gasoline Vapor Emissions from Enclosed Fuel Tanks |url=https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100GPED.TXT |website=nepis.epa.gov |publisher=United States Environmental Protection Agency}}</ref> Its research and motor ] are 75 and 71 respectively.<ref>{{Cite book |last=Scherzer |first=Julius |url=https://books.google.com/books?id=0R2qSCsVT3cC&pg=PA9 |title=Octane-Enhancing Zeolitic FCC Catalysts: Scientific and Technical Aspects |date=1990 |publisher=CRC Press |isbn=978-0-8247-8399-0 |pages=9 |language=en}}</ref>
			As a component of a mixture, it is usually dehydrogenated to toluene, which increases the octane rating of gasoline.<ref name="Ullmann" />
			:] is a classic ] reaction. This platinum (Pt)-catalyzed process is practiced on scale in the production of ] from petroleum.<ref name=Gary>{{cite book|author1=Gary, J.H. |author2=Handwerk, G.E.|title=Petroleum Refining Technology and Economics|edition=2nd|publisher=Marcel Dekker, Inc|year=1984|isbn=0-8247-7150-8}}</ref>]]
			It is also one of a host of substances in ] blends, e.g., for ] fuel.<ref>Tim Edwards, Meredith Colket, Nick Cernansky, Fred Dryer, Fokion Egolfopoulos, Dan Friend, Ed Law, Dave Lenhert, Peter Lindstedt, Heinz Pitsch, Adel Sarofim, Kal Seshadri, Mitch Smooke, Wing Tsang & Skip Williams, 2007, AIAA2007-770: Development of an Experimental Database and Kinetic Models for Surrogate Jet Fuels, 45th AIAA Aerospace Sciences Meeting and Exhibit, 8-11 January 2007, Reno, Nevada, DOI 10.2514/6.2007-770, see , accessed 27 May 2014.</ref><ref>Meredith Colket, Tim Edwards, Fred Dryer, Skip Williams, Nicholas Cernansky, David Miller, Fokion Egolfopoulos, Frederick Dryer & Josette Bellan, 2008, AIAA 2008-972: Identification of Target Validation Data for Development of Surrogate Jet Fuels, 46th AIAA Aerospace Sciences Meeting and Exhibit, 8-11 January 2007, Reno, Nevada, DOI 10.2514/6.2008-972, see , accessed 27 May 2014.</ref>
			===Solvent===
			Methylcyclohexane is used as an ], with properties similar to related saturated hydrocarbons such as ].<ref>D. Bryce-Smith and E. T. Blues "Unsolvated n-Butylmagnesium Chloride" Org. Synth. 1967, 47, 113. {{doi|10.15227/orgsyn.047.0113}}</ref> It is also a solvent in many types of correction fluids.
	==Structure==		==Structure==
	'''Monosubstituted''' methylcyclohexane has one methyl branch on one carbon of the ] ring. Like all substituted cyclohexanes, it can ring-flip rapidly between two ]. However, a monosubstituted Methylcyclohexane exists almost exclusively in the equatorial position rather than axial. When the methyl group occupies the axial position, there is steric crowding (steric strain) by the axial hydrogens on the same side of the ring (known as the ]). There are two such interactions, with each methyl/hydrogen pair contributing approximately 7.61 kJ/mol strain. However, the equatorial conformation experiences no such interaction so it is more stable.		Methylcyclohexane is a monosubstituted ] because it has one branching via the attachment of one ] on one carbon of the cyclohexane ring. Like all cyclohexanes, it can interconvert rapidly between two ]. The lowest ] form of this monosubstituted methylcyclohexane occurs when the methyl group occupies an ] rather than an ]. This equilibrium is embodied in the concept of ]. In the axial position, the methyl group experiences steric crowding (steric strain) because of the presence of axial hydrogen atoms on the same side of the ring (known as the ]). There are two such interactions, with each pairwise methyl/hydrogen combination contributing approximately 7.61 kJ/mol of strain energy. The equatorial conformation experiences no such interaction, and so it is the energetically favored conformation.
			==Flammability and toxicity==
	==Disubstituted cyclohexanes==
			Methylcyclohexane is flammable.
	{{Main|Cyclohexane conformation}}
	Cyclohexanes could also have more than one methyl branch. '''Disubstituted''' cyclohexane, or also known as '''dimethylcyclohexane''' has two methyl branches. Unlike the monosubstituted cyclohexane, there are several possible structures. The methyl groups could be on the same carbon, separate carbons and it doesn't necessarily have to be on the same face. The 1,3-diaxial strain interactions still apply to the disubstituted. If the methyl groups are on different faces and both in axial positions, there are diaxial interactions with the axial hydrogen groups on both faces. If they are on the same face, both methyl groups interact with the one hydrogen that is in axial position and there is also a methyl-methyl interaction with a steric energy of approximately 15.3 kJ/mol. If the methyl groups are on adjacent carbons of the cyclohexane, with one of them axial and the other equatorial, there would be a gauche interaction which adds to the total strain energy the molecule has. For the dimethylcyclohexane which has two methyl groups on one carbon (1,1-dimethylcyclohexane), one methyl group is axial and the other equatorial. It would have the same total strain energy as the monosubstituted cyclohexane with axial methyl.
			Furthermore, it is considered "very toxic to aquatic life".<ref>Chevron Phillips, 2014, "Material Safety Data Sheet: Methylcyclohexane (v. 1.5)", see , accessed 23 May 2014.</ref> Note, while methylcyclohexane is a ] of ] (MCHM), it is distinct in its physical, chemical, and biological (ecologic, metabolic, and toxicologic) properties.<ref>CDC, 2014, "Methylcyclohexane," NIOSH Pocket Guide to Chemical Hazards, see , accessed 27 May 2014.</ref>
	]
			== References ==
			{{Reflist}}
			{{Authority control}}
	]		]
	]		]
			]
			]
	]
	]
	]
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	]