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

[7] 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.