p-Menthane is a hydrocarbon with the formula (CH3)2CHC6H10CH3. It is the product of the hydrogenation or hydrogenolysis of various terpenoids, including p-cymene, terpinolenes, phellandrene, and limonene. It is a colorless liquid with a fragrant fennel-like odor. It occurs naturally, especially in exudates of Eucalyptus fruits. The compound is generally encountered as a mixture of the cis and trans isomers, which have very similar properties. It is mainly used as a precursor to its hydroperoxide, which is used to initiate polymerizations.[1]