Abstract: The present invention relates to the field of organic synthesis and more particularly to a new process for the preparation of a compound of formula (I), in the form of any one of its isomers or a mixture thereof, wherein, more preferably, G represents a C?O group, R1 represents a butyl group and R2 represents a methyl group. The process of the invention involves an 2-(1-hydroxyalkyl)-cyclopent-2-en-1-one derivative, as starting material, which can be then converted into a compound of formula (I) by a process comprising a thermal rearrangement. The 2-alkylidene-3-oxo-cyclopentylacetate derivative and the 2-(1-hydroxyalkyl)-cyclopent-2-en-1-one derivative are also an object of the invention.

Abstract: The present invention relates to the field of organic synthesis and more particularly to a new process for the preparation of a compound of formula (I), in the form of any one of its isomers or a mixture thereof, wherein, more preferably, G represents a C?O group, R1 represents a butyl group and R2 represents a methyl group. The process of the invention involves an 2-(1-hydroxyalkyl)-cyclopent-2-en-1-one derivative, as starting material, which can be then converted into a compound of formula (I) by a process comprising a thermal rearrangement. The 2-alkylidene-3-oxo-cyclopentylacetate derivative and the 2-(1-hydroxyalkyl)-cyclopent-2-en-1-one derivative are also an object of the invention.

Abstract: A supporting disc for a supporting disc bearing of open-end spinning rotors consists of a disc-like base body and a running ring made of plastic. There are small, ball-shaped filling bodies, preferably of glass, embedded in the running ring. These filling bodies, which amount to between 0.1 and 10% of the total volume, have a diameter of, for example, 0.1 to 0.3 mm. After the peripheral surface of the running ring has been machined, a more or less porous running surface arises.

Abstract: 3a,6,6,9a-Tetramethylperhydronaphto[2,1-b]furan, a typical ambergris perfume ingredient is prepared via a novel process from 1.beta.-(2-hydroxyethyl)-perhydro-2,5,5,8a.beta.-tetramethyl-2.beta.-trans -napthalenol by cyclization with an acidic cyclization agent in the presence of nitromethane.

Abstract: 3a,6,6,9a-Tetramethylperhydronaphto[2,1-b]furan, a typical ambergris perfume ingredient is prepared via a novel process from 1.beta.-(2-hydroxyethyl)-perhydro-2,5,5,8a.beta.-tetramethyl-2.beta.-trans -naphthalenol by cyclization with an acidic cyclization agent in the presence of nitromethane.

Abstract: 3a,6,6,9a-Tetramethylperhydronaphto[2,1-b]furan, a typical ambergris perfume ingredient is prepared via a novel process from 1.beta.-(2-hydroxyethyl)-perhydro-2,5,5,8a.beta.-tetramethyl-2.beta.-trans -naphthalenol by cyclization with an acidic cyclization agent in the presence of nitromethane.

Abstract: New unsaturated macrocyclic ketones are obtained via a process which consists in reacting a dialdehyde with a tetraalkyldiphosphonate ester. The new ketones are useful intermediates for the preparation of cyclopentadecanone and its higher methyl-homologue, known fragrant substances. New ketones possess also direct utility as musky odorants.

Abstract: New unsaturated macrocyclic ketones are obtained via a process which consists in reacting a dialdehyde with a tetraalkyldiphosphonate ester. The new ketones are useful intermediates for the preparation of cyclopentadecanone and its higher methyl-homologue, known fragrant substances. New ketones possess also direct utility as musky odorants.

Abstract: 9-Hydroxy-undeca-4,10-dien-1-al, a novel unsaturated aliphatic hydroxy-aldehyde, has been found to possess useful odorous properties and consequently can be advantageously used as perfume ingredient.

Abstract: New cycloaliphatic unsaturated ketones and their use as perfuming and odor-modifying agents in the manufacture of perfumes and perfumed products, and as flavoring and taste-modifying agents in the preparation of foodstuffs in general and imitation flavors for foodstuffs, beverages, animal feeds, pharmaceutical preparations and tobacco products.Methods for preparing the said new compounds and certain of the starting materials used for their synthesis.

Abstract: The present invention relates to a novel process for preparing unsaturated aldehydes comprising four double bonds of formula ##SPC1##Wherein one of the double bonds is represented by the dotted lines. Aldehyde Ia (called .alpha.-sinensal) corresponds to the above formula wherein the double bond represented by the dotted lines is in the main carbon chain. Aldehyde Ib (called .beta.-sinensal) corresponds to the above formula wherein the double bond represented by the dotted lines is in the side chain. The invention also relates to new intermediates used in the said new process and to methods for preparing them. The said intermediates have also valuable organoleptic properties and are useful as fragrances in the preparation of perfumes, perfumed products and artificial essential oils.

Abstract: Process for the preparation of unsaturated aldehydes, in particular .gamma.,.delta.-unsaturated aldehydes, which comprises reacting an amino-nitrile with a basic or a neutral agent.The products obtained in accordance with the process of the invention are useful intermediates for the preparation of flavoring ingredients.

Abstract: The present invention relates to a novel process for preparing unsaturated aldehydes comprising four double bonds of formula ##SPC1##Wherein one of the double bonds is represented by the dotted lines. Aldehyde Ia (called .alpha.-sinensal) corresponds to the above formula wherein the double bond represented by the dotted lines is in the main carbon chain. Aldehyde Ib (called .beta.-sinensal) corresponds to the above formula wherein the double bond represented by the dotted lines is in the side chain. The invention also relates to new intermediates used in the said new process and to methods for preparing them. The said intermediates have also valuable organoleptic properties and are useful as fragrances in the preparation of perfumes, perfumed products and artificial essential oils.