Abstract: A compound of formula ##STR1## wherein X represents a C.dbd.O group or a CH--OH group, in the form of an optically active isomer of formula ##STR2## wherein X has the meaning indicated above and, when X is a CH--OH group, the asymmetric carbon (2) has an R configuration, or in the form of a mixture of isomers, is very useful in the field of perfumery, having an unusual, fruity odor note that can be described as a fresh walnut odor together with a rhum type note.

Abstract: 3-Methyl-2-oxo-ethylpentanoate or an isomer thereof are very useful compounds in the field of perfumery, having an unusual, fruity odor note that can be described as a fresh walnut odor together with a rum type note.

Abstract: 3-(2,2-Dimethyl-propyl)-pyridine is used to impart, improve or modify the odor properties of a variety of consumer products. In particular, it develops fruity-fresh type notes.

Abstract: Perhydro-5,5-8a-trimethyl-2-naphthalenone is prepared by acid cyclization of carboxylic esters of formula ##STR1## having a double bond in one of the positions indicated by the dotted lines and wherein symbol R designates a C.sub.1 -C.sub.6 alkyl radical, X stands for a monovalent radical of formula P(O)(OR.sup.1).sub.2 or C(O)R.sup.2, R.sup.1 represents a C.sub.1 -C.sub.6 alkyl group and R.sup.2 is either a linear or branched alkyl group or a substituted or unsubstituted phenyl radical, and wherein the wavy line represents a C--C bond of cis or trans configuration, or of formula ##STR2## wherein the wavy lines and symbol R are defined as above, and R.sup.0 represents a C.sub.3 -C.sub.6 alkyl radical, preferably branched, followed by basic decarboxylation of the obtained product.

Abstract: Perhydro-5,5-8a-trimethyl-2-naphthalenone is prepared by acid cyclization of carboxylic esters of formula ##STR1## having a double bond in one of the positions indicated by the dotted lines and wherein symbol R designates a C.sub.1 -C.sub.6 alkyl radical, X stands for a monovalent radical of formula P(O)(OR.sup.1).sub.2 or C(O)R.sup.2, R.sup.1 represents a C.sub.1 -C.sub.6 alkyl group and R.sup.2 is either a linear or branched alkyl group or a substituted or unsubstituted phenyl radical, and wherein the wavy line represents a C--C bond of cis or trans configuration, or of formula ##STR2## wherein the wavy lines and symbol R are defined as above, and R.sup.0 represents a C.sub.3 -C.sub.6 alkyl radical, preferably branched, followed by basic decarboxylation of the obtained product.

Abstract: Compounds of formula ##STR1## having a double bond in one of the positions indicated by the dotted lines and wherein symbol R represents a hydrogen atom or a methyl radical, are useful ingredients for the preparation of perfuming compositions and perfumed articles, to which they impart odor notes of the woody-amber type.

Abstract: Process for the preparation of polycyclic ethers of formula ##STR1## wherein X represents --(CH.sub.2).sub.n --, index n stands for integer 0 or 1, symbol R.sup.4 designated a hydrogen atom or a methyl radical, R.sup.2 identical or different, represent each a hydrogen atom or a lower alkyl radical from C.sub.1 to C.sub.3 and R designates either a C.sub.1 to C.sub.6 linear or branched alkyl radical, or a substituted or unsubstituted alkenyl radical having 2 or 3 carbon atoms in the main chain, said alkenyl radical forming a ring such as indicated by the dotted line, which process comprises the cyclization by means of an acidic agent of an unsaturated compound:a) of formula ##STR2## having a double bond in one of the positions indicated by the dotted lines, and wherein index m defines an integer number equal to 1 or 2, symbol R.sup.

Abstract: Process for the preparation of polycyclic ethers of formula ##STR1## wherein X represents --(CH.sub.2).sub.n --, index n stands for integer 0 or 1, symbol R.sup.4 designates a hydrogen atom or a methyl radical, symbols R.sup.1 and R.sup.2, identical or different, represent each a hydrogen atom or a lower alkyl radical from C.sub.1 to C.sub.3 and R designates either a C.sub.1 to C.sub.6 linear or branched alkyl radical, or a substituted or unsubstituted alkenyl radical having 2 or 3 carbon atoms in the main chain, said alkenyl radical forming a ring such as indicated by the dotted line, which process comprises the cyclization by means of an acidic agent of an unsaturated compound:a) of formula ##STR2## having a double bond in one of the positions indicated by the dotted lines, and wherein index m defines an integer number equal to 1 or 2, symbol R.sup.

Abstract: Process for the preparation of polycyclic ethers of formula ##STR1## wherein X represents --(CH.sub.2).sub.n --, index n stands for integer 0 or 1, symbol R.sup.4 designates a hydrogen atom or a methyl radical, symbols R.sup.1 and R.sup.2, identical or different, represent each a hydrogen atom or a lower alkyl radical from C.sub.1 to C.sub.3 and R designates either a C.sub.1 to C.sub.6 linear or branched alkyl radical, or a substituted or unsubstituted alkylene radical having 2 or 3 carbon atoms in the main chain, said alkylene radical forming a ring such as indicated by the dotted line, which process comprises the cyclization by means of an acidic agent of an unsaturated compound:a) of formula ##STR2## having a double bond in one of the positions indicated by the dotted lines, and wherein index m defines an integer number equal to 1 or 2, symbol R.sup.

Abstract: Nitrogen containing compounds of formula ##STR1## wherein symbol R designates a C.sub.1 -C.sub.3 alkyl group, each of R.sup.1 and R.sup.2 represents, when taken separately, a C.sub.1 -C.sub.6 alkyl radical or, when taken together, a polymethylene and R.sup.3 represents a C.sub.1 -C.sub.3 alkyl group, preferably a methyl radical, or a hydrogen atom.Process for their preparation comprising the addition of an amine of formula ##STR2## to an aldehyde of formula ##STR3## Use of said compounds (I) as starting materials for the preparation of decalin ketone derivatives of general formula ##STR4## containing a double bond in one of the positions indicated by the dotted lines and wherein R.sup.4 designates a hydrogen atom or a methyl radical, and symbols R and R.sup.3 have the meaning indicated for formula (I).

Abstract: Polyunsaturated ketones of formula ##STR1## having a double bond in position 2' or 3' of the side chain and possessing either an isolated double bond in position 1 or 2, or two conjugated double bonds in positions 1 and 3 of the ring, as indicated by the dotted lines, andwhereinindex n stands for integer 1 or 2, andeach of the symbols R.sup.1 to R.sup.7, identical or different, designates a hydrogen atom or a lower radical,are prepared by a process which makes use of tertiary diallyl carbinols as starting materials.

Abstract: Polyunsaturated ketones of formula ##STR1## having a double bond in position 2' or 3' of the side chain and possessing either an isolated double bond in position 1 or 2, or two conjugated double bonds in positions 1 and 3 of the ring, as indicated by the dotted lines, and whereinindex n stands for integer 1 or 2, andeach of the symbols R.sup.1 to R.sup.7, identical or different, designates a hydrogen atom or a lower alkyl radical,are prepared by a process which makes use of tertiary diallyl carbinols as starting materials.

Abstract: Useful perfumery ingredients delta- and epsilon-damascone are prepared by a process which consists in an anionic cleavage, in the presence of a strong base of a diallyl alcohol of formula ##STR1## wherein the dashed lines in position 3 or 4 of the ring designate a double bond, followed by an isomerization of the terminal double bond of the thus obtained product by means of an acidic isomerizing agent.

Abstract: .alpha.,.beta.-and .beta.,.gamma.-unsaturated ketones of formula ##STR1## possessing a double bond in one of the positions indicated by the dashed lines and wherein R and R.sup.1 have the meaning given above and index n stands for integer 1 or 2, are obtained by a process which consists in treating with a strong base in an inert organic solvent a diallyl carbinol of formula ##STR2## wherein symbol R represents a primary, secondary or tertiary alkyl radical, or a substituted or unsubstituted phenyl radical, and symbol R.sup.1 represents a hydrogen atom or an alkyl radical.

Abstract: Hydroxy-ketones having formula ##STR1## possessing a double bond in one of the positions indicated by the dotted lines, are prepared starting from a diallyl carbinol of formula ##STR2## Hydroxy-ketones (Ia, b) are useful as intermediates for the preparation of rose oxide.