l-Dihydromyrcene (2) was obtained from l-cis-pinane (1) when (1) was thermally isomerized with the catalyst systems composed of copper and zinc, at 378 ± 2°C under a reduced pressure.
In a similar fashion, 6-methyl-2-vinyl-5-hepten-l-ol (4) and 2- (2-methylpro-peny1) -5-hexen-l-ol (5) were obtained by the isomerization of myrtanol (6, 6-di-methyl-bicyclo [3.1.1.] -heptan-2-methanol) (3).
In this method, the optical activity of (2) is retained and amounts of by-pro-ducts were less than those of conventional means.