A fragrance composition comprising a compound represented by Formula (1): wherein, in Formula (1), R represents a linear or branched alkyl group having from 2 to 3 carbon atoms or a cyclic alkyl group having from 3 to 6 carbon atoms.

##STR00001##

A compound, represented by Formula (1): where X represents an isopropyl group or a t-butyl group, and R represents a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms; provided that one where X is an isopropyl group, and R is a t-butyl group is excluded.

##STR00001##

Described herein is a process including alpha alkylation of an aldehyde with a polycyclic olefin followed by a ring opening step in order to provide a compound of formula

##STR00001##

in a form of any one of its stereoisomers or a mixture thereof and where n represents 1 to 4 and R.sup.2 to R.sup.5 represent independently of each other, a hydrogen atom or a C.sub.1-6 linear alkyl group or a C.sub.3-6 branched alkyl group; and R.sup.3 and R.sup.4 or R.sup.5 or, alternatively, R.sup.2 and R.sup.3 when taken together form a saturated or unsaturated optionally substituted 5 or 6 membered carbocyclic ring.

Described herein is a method of using, as perfuming ingredients, e.g. to impart odor notes of the fruity, fruity-exotic types, cyclopentanone compounds of formula

##STR00001##

in a form of any one of its stereoisomers or a mixture thereof, and wherein n represents 1 or 2.

The present invention relates to novel compounds and their use as fragrance materials.

The present invention relates to the use of a compound of the general formula (I) wherein R.sup.1 is C.sub.1-C.sub.4-alkyl or (C=0)R.sup.3, R.sup.2 is hydrogen, C.sub.1-C.sub.4-alkyl or (C=0)R.sup.4, and R.sup.3 and R.sup.4, independently of one another, are selected from the group consisting of hydrogen and C.sub.1-C.sub.4-alkyl, a stereoisomer thereof or a mixture of stereoisomers thereof, as an aroma chemical, to aroma chemical compositions comprising at least one compound of the general formula (I), a stereoisomer thereof or a mixture of stereoisomers thereof, and to a method for preparing a fragranced ready-to-use composition, which comprises incorporating at least one compound of the general formula (I), a stereoisomer thereof or a mixture of stereoisomers thereof, into a ready-to-use composition. The present invention further relates to specific ethers and specific esters of the compounds of the general formula (I) and a method for their preparation.

##STR00001##

Disclosed is a use of a compound of formula (I), a composition of matter comprising a compound of formula (I) and a consumer product comprising a compound of formula (I).

##STR00001##

The present invention relates to new classes of odorous ketones (odorants) which are useful as fragrance or flavor materials in particular in providing coniferous, thuya, floral and/or fruity olfactory notes to perfume, aroma or deodorizing/masking compositions.

Described herein is a method of using as perfuming ingredients, e.g. to impart odor notes of the fruity, fruity-exotic types, cyclopentanone compounds of formula ##STR00001##
in a form of any one of its stereoisomers or a mixture thereof, and wherein n represents 1 or 2.

Fragrance precursor compounds of the formula (I) may be derived from hydrazides and fragrance aldehydes and ketones. The fragrance precursor compounds may be used in composition having washing or cleaning agents, cosmetic agents and air care agents. A method for long-lasting fragrancing of surfaces using the fragrance precursor compounds and agents is also disclosed.