| abstract |
A process is described for the preparation of a compound of formula in which the dotted lines indicate the location of a single or double bond, the symbol R¹ represents a hydrogen atom or a methyl radical, the symbol R² represents a C radical to C₄ alkyl radical, saturated or unsaturated, of linear chain or branched and the symbol R³ represents a methyl, ethyl or methylene radical, excluding 1- (2,2,3,6-tetramethyl-1-cyclohexyl) -1-hexen-3-one and 1 - (2,2,3,6-tetramethyl-1-cyclohexyl) -3-hexanone, the process being characterized in that a compound of formula is treated in which the dotted lines and the symbol R³ are defined as above, with a Lewis acid to obtain an aldehyde of formula in which the dotted lines and the symbol R³ have the meaning indicated above and this aldehyde is transformed into the compound (I) using reactions of conventional type.n n n This process makes it possible to obtain new compounds of formula in which the dotted lines indicate the location of a single or double bond, the symbol R¹ represents a hydrogen atom or a methyl radical, the symbol R² represents a C radical to C₄ alkyl radical, saturated or unsaturated, of linear chain or branched, excluding 4- (2,2,3,6-tetramethyl-1-cyclohexyl) -2-butanone, 4- (2,2,3,6-tetramethyl-1-cyclohexyl) - 3-buten-2-one, 1- (2,2,3,6-tetramethyl-1-cyclohexyl) -1-hexen-3-one and 1- (2,2,3,6-tetramethyl-1-cyclohexyl) -3-hexanone , as well as particular isomeric forms of these compounds. The compounds (Ia) have interesting olfactory properties and are therefore useful, as perfume ingredients, for the preparation of perfume compositions and perfume articles. |