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.
As of early 1990s, it was present in American and European gasoline in small amounts, and by 2011 its share in US gasoline varied between 1 and 3%. It has a research octane number of 103 and motor octane number of 95.
The C₆ core of methylcyclopentane is not perfectly planar and can pucker to alleviate stress in its structure.

History

Methylcyclopentane was first synthesized in 1888 by and William [Henry Perkin Jr.|W. H. Perkin Jr.] by a Wurtz reaction of sodium and 1,5-dibromohexane. 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 had tried and failed to synthesize cyclohexane using this method.