Methylcyclopentane

Methylcyclopentane is an organic compound with the chemical formula CH₃C₅H₉. It is a colourless, flammable liquid with a faint odor. It is a component of the naphthene fraction of petroleum usually obtained as a mixture with cyclohexane. It is mainly converted in naphthene reformers to benzene.^[2]

Methylcyclopentane

Names
Preferred IUPAC name Methylcyclopentane
Identifiers
CAS Number	96-37-7 N
3D model (JSmol)	Interactive image
ChEBI	CHEBI:88429
ChEMBL	ChEMBL30940
ChemSpider	7024 N
ECHA InfoCard	100.002.277
EC Number	202-503-2
PubChem CID	7296
UNII	5G26CC1ASK
UN number	2298
CompTox Dashboard (EPA)	DTXSID3025590
InChI InChI=1S/C6H12/c1-6-4-2-3-5-6/h6H,2-5H2,1H3
SMILES CC1CCCC1
Properties
Chemical formula	C6H12
Molar mass	84.162 g·mol−1
Appearance	Colorless liquid
Density	0.749 g/cm3[1]
Melting point	−142.4 °C (−224.3 °F; 130.8 K)[1]
Boiling point	71.8 °C (161.2 °F; 344.9 K)[1]
Solubility in water	Insoluble
Magnetic susceptibility (χ)	−70.17·10−6 cm3/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	flammable
Flash point	−4 °C (25 °F; 269 K)
Autoignition temperature	260 °C (500 °F; 533 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

As of early 1990s, it was present in American^[3] and European^[4] gasoline in small amounts, and by 2011 its share in US gasoline varied between 1 and 3%.^[5] It has a research octane number of 103 and motor octane number of 95.^[6]

The C₆ core of methylcyclopentane is not perfectly planar and can pucker to alleviate stress in its structure.^[7]

The conversion of methylcyclopentane to benzene is a classic aromatization reaction, specifically a dehydroisomerization. This platinum (Pt)-catalyzed process is practiced on scale in the production of gasoline from petroleum.

History

Methylcyclopentane was first synthesized in 1888 by Paul Caspar Freer [Wikidata] and W. H. Perkin Jr. by a Wurtz reaction of sodium and 1,5-dibromohexane.^[8] They named it methylpentamethylene since the modern nomenclature wasn't developed until 1892 Geneva Rules.

In 1895, Nikolai Kischner discovered that methylcyclopentane was the reaction product of hydrogenation of benzene using hydriodic acid. Prior to that, several chemists (such as Marcellin Berthelot in 1867,^[9][10] and Adolf von Baeyer in 1870^[11]) had tried and failed to synthesize cyclohexane using this method.