Patent ID: 8546591

Claim:
A process for the preparation of cis-2-(2-methylprop-1-enyl)-4-methyltetrahydropyran of the formula (I) comprising the steps a) catalytic hydrogenation of 2-(2-methylprop-1-enyl)-4-methylenetetrahydropyran of the formula (II) in the presence of hydrogen and a heterogeneous catalyst comprising ruthenium on a support to give a reaction mixture comprising the compound of the formula (I) and trans-2-(2-methylprop-1-enyl)-4-methyltetrahydropyran of the formula (III) and b) if appropriate separating off the compounds of the formulae (I) and (III) from the reaction mixture obtained according to step a) and c) bringing the compounds of the formulae (I) and (III) obtained in step a) or b) into contact with a strongly acidic cation exchanger with isomerization of the compound of the formula (III) to give the compound of the formula (I).