Alicyclic aliphatic 1,3-dicarbonyl derivatives useful as fragrances

A compound of formula (I)

• wherein
• R1 and R3 are independently selected from hydrogen, methyl and ethyl;
• R2 is hydrogen, methyl, ethyl, or methylene;
• R4 is H, or C1-C4 alkyl;
• R5 is H, or methyl;
• R6 is selected from hydrogen and methyl;
• X is selected from the group consisting of the bivalent residues >CH2, >O, >CHMe, >CMe2;
• and
• the bond between C-2 and R2 is a single bond, and the bond between C-2 and C-3 together with the dotted line represents a double bond;
• or
• the bond between C-2 and C-3 is a single bond, and the bond between C-2 and R2 together with the dotted line represents a double bond;
• or
• the bond between C-2 and R2 is a single bond, and the bond between C-2 and C-3 is a single bond.