Abstract: A process for the preparation of vitamin A which preferably comprises bringing cyclogeranyl sulphone into contact with a C.sub.10 aldehyde acetal, halogenating the derivative obtained and then removing the halogen group and the sulphone, removing the acetal group and isomerizing the retinal obtained to the desired configuration. Also disclosed are compounds useful as intermediates in the synthesis of vitamin A and processes for preparation of these intermediate compounds.

Abstract: Alimentary and/or medicinal active principles intended for feeding or treating ruminants are polished by spraying a solution of one or more active principles, resins and/or sugars onto the said active principles. The polished active principles are then coated with a polymer providing protection in the rumen.

Abstract: A process for coating at least one medicinal and/or foodstuff active principle useful for ruminants. At least one monomer is polymerized in an oil-in-water emulsion in the presence of a surfactant to synthesize a pH-sensitive-polymer composition, the composition being obtained in an oil-in-water emulsion. Without isolation of the pH-sensitive polymer, the oil-in-water emulsion is used to coat the active principle, preferably methionine or lysine or a derivative thereof. The pH-sensitive polymer is not dissolved in an organic solvent(s) in either the polymerization or coating steps. The pH-sensitive polymer is stable at pH 6 but at pH 2, the coated active principle is released.

Abstract: The present invention relates to a process for preparing halo acetals of ethylenic aldehydes by reaction of a halogen cation with enamine followed by a hydrolysis and reaction with an alcohol, a glycol or an orthoformate. These halo acetals are used as intermediate for the synthesis of vitamins A and E.It also relates to a new compound of formula (IV), ##STR1## to a process for preparing it from halo acetals of ethylenic aldehydes by reaction with triethyl phosphate, and to its use for the preparation of retinal by reaction with .beta.-ionylideneacetaldehyde.

Abstract: The present invention relates to new granules, as well as the process for their preparation, obtained by extrusion of a mixture containing a meltable binder in an amount such that it permits the passage of the mixture through a die. The granules obtained are then coated with a polymer permitting their trans-rumen passage without degradation. After coating, these granules are used for animal feeding of ruminants.

Abstract: New intermediates and processes for the preparation of vitamins A and E, which are the acetals of 5,6-dihalo-3-methyl-3-hydroxyhexanal or of 6-halo-3-hydroxy-3-methyl-5-hexenal or 3-methyl-3-hydroxy-5-hexenal, as well as processes for making the intermediates. After dehydrohalogenation and dehydration these intermediates are condensed directly with .beta.-ionone or with 2-methyl-2-heptene-6-one to synthesize vitamins A and E respectively.

Abstract: The present invention relates to dihydropyran derivatives, processes for preparing, and processes of using the derivatives. The derivatives are prepared by condensation of lithium dienolate of prenal with an aldehyde or a ketone.The pyran derivative prepared from .beta.-ionylideneacetaldehyde when treated in the presence of a catalyst directly forms retinal.

Abstract: A method of making cheese with milk obtained from animals which have received feed supplemented or complemented with an amino acid in a protected form. The amino acid is preferably lysine and/or methionine.

Abstract: A new method of coating an active principle which comprises the step of coating an active principle with an aqueous emulsion or dispersion containing one or more pH-sensitive polymers.

Abstract: A process for the purification of pseudo-ionone, which comprises preparing pseudo-ionone by a reaction of citral with acetone, followed by bringing the reaction medium into contact with a metal derivative and thereafter distilling the pseudo-ionone.

Abstract: The invention relates to a process for preparing unsaturated aldehydes and their enamines by the oxidation of allylic tertiary amines in the presence of an alkyl hydroperoxide and a vanadium-based catalyst.

Abstract: A process for the preparation of citral by the cracking of prenal diprenyl acetal in a vapor phase in the presence of a heterogeneous type of acid catalyst.

Abstract: A process for preparing cyclocitral by expoxidizing a pyronene.

Abstract: Epoxides represented by the formula: ##STR1## in which A represents a methylene or oxirane group and a process for their preparation.

Abstract: The present invention relates to dihydropyran derivatives, processes for preparing, and processes of using the derivatives. The derivatives are prepared by condensation of lithium dienolate of prenal with an aldehyde or a ketone.The pyran derivative prepared from .beta.-ionylideneacetaldehyde when treated in the presence of a catalyst directly forms retinal.

Abstract: A process for converting tertiary amine N-oxides to aldehydes by reacting tertiary amine N-oxides in the presence of a catalytic quantity of a vanadium containing compound.

Abstract: The present invention relates to a process for preparing halo acetals of ethylenic aldehydes by reaction of a halogen cation with enamine followed by a hydrolysis and reaction with an alcohol, a glycol or an orthoformate. These halo acetals are used as intermediate for the synthesis of vitamins A and E.It also relates to a new compound of formula (IV), ##STR1## to a process for preparing it from halo acetals of ethylenic aldehydes by reaction with triethyl phosphate, and to its use for the preparation of retinal by reaction with .beta.-ionylideneacetaldehyde.

Abstract: A sulpholene compound and more particularly 4,4-dimethyl-2,2-dioxo-1,2,4,5,6,7-hexahydro-benzo[c]thiophene. These compounds are prepared by bringing myrcene sulphone into contact with a strong acid. The compounds of the present invention can be used as synthesis intermediates in the preparation of vitamin A.

Abstract: New intermediates and processes for the preparation of vitamins A and E, which are the acetals of 5,6-dihalo-3-methyl-3-hydroxyhexanal or of 6-halo-3-hydroxy-3-methyl-5-hexenal or 3-methyl-3-hydroxy-5-hexenal, as well as processes for making the intermediates. After dehydrohalogenation and dehydration these intermediates are condensed directly with .beta.-ionone or with 2-methyl-2-heptene-6-one to synthesize vitamins A and E respectively.

Abstract: A sulpholene compound and more particularly 4,4-dimethyl-2,2-dioxo-1,2,4,5,6,7-hexahydro-benzo[c]thiophene. These compounds are prepared by bringing myrcene sulphone into contact with a strong acid. The compounds of the present invention can be used as synthesis intermediates in the preparation of vitamin A.