| 摘要 |
<p>There is disclosed a process for preparing unsaturated ketones especially terpenoid ketones, by subjecting a substituted propargyl alcohol of formula (II) <IMAGE> (II) wherein R is a group containing 1 or 2 substituted or unsubstituted alkyl- or alkylene units containing 4 carbon atoms each to a thermal treatment sufficient to rearrange its structure in order to obtain structurally isomeric unsaturated ketones of formula I <IMAGE> (I) wherein one of the substituents X3 and X4 is hydrogen and the other and Z2 together form a bond. The process can be effected in the presence of an isomerization catalyst, which leads to high percentage of alpha . beta , gamma . delta -unsaturated ketones. The ketones of formula I are useful as perfumes and as intermediates for the production of terpenoid compounds.</p> |
