4-Methylcyclohexene is an organic compound consisting of cyclohexene with a methyl group substituent attached to carbon most distant from the alkene group. Two other structural isomers are known: 1-methylcyclohexene and 3-methylcyclohexene. All are colorless volatile liquids classified as a cyclic olefins. They are specialized reagents.
Methylcyclohexenes are formed by the partial hydrogenation of toluene to methylcyclohexane over ruthenium catalyst.[1]
In the presence of a Cinchona alkaloid, bromination of an alkene can leads to optically active dibromides.[2] For 4-methylcyclohexene, the (S)-configuration leads to two different products: the bromines can add at the axial positions, giving the orientation (1S,3R,4R), or at the equatorial positions, giving the orientation (1S,3S,4S). Similarly, the (R)-configuration produces two different products: axial addition yields the configuration (1R,3S,4S) and equatorial addition yields (1R,3R,4R).