2,2,4-Trimethylpentane

2,2,4-Trimethylpentane, also known by the common name isooctane or iso-octane, is an organic compound. It is one of the isomers of octane, an alkane with chemical formula . It is used to define the octane rating scale used for measuring gasoline: pure 2,2,4-trimethylpentane has an octane rating of 100.

 Name 
"Isooctane" is not a systematic name. For lighter hydrocarbons, "iso" is used to mean the isomer of an alkane that has a single branch at the end of the main carbon chain. For octane, this isomer is 2-methylheptane.

Category:Alkanes