A process for the preparation of saturated monocyclic monoterpenes from moncyclischer monoterpenes

摘要

1318598 Saturated monocyclic terpenes CHEMISCHE WERKE HULS AG 19 Oct 1970 [20 Oct 1969] 49528/70 Heading C5E A saturated monocyclic terpene is prepared by hydrogenating an ether of a monocyclic terpene at superatmospheric pressure and elevated temperature in the presence of a catalyst which in the unreduced condition contains: 10-60 wt. per cent Ni, 10-87À3 wt. per cent calcined Al 2 O 3 , 0-40 wt. per cent ZnO and 0-5 wt. per cent SiO 2 . Preferably the feedstock is eucalyptol, which may also contain unsaturated monocyclic terpenes such as limonenes, dipentene, α-terpininene, and terpinols; the product being p-menthane. Up to 80 wt. per cent of a conventional nickel impregnation catalyst may be employed with the Ni-Al 2 O 3 catalyst. The reaction may be effected at 100-300‹ C. and 50-350 atmos. gauge.