Rhone-poulenc Nutrition Animale

Rhone-poulenc Chimie

Jean-Marie Poirier

Pierre Duhamel

Lucette Duhamel

Jerome Guillemont

Pierre F Chabardes

Bertrand Leblond

Pierre F Charbardes

The present invention relates to new fluorinated hexane compounds corresponding to the following general formula (II): ##STR1## in which X'.sub.2, X'.sub.3, and X'.sub.4 are the same or different, and denote a halogen or a pseudohalogen, preferably a halogen, more preferably chlorine and fluorine, with the condition that, when R.sub.1 is hydroxyl, cyano, amido, imido, ethoxy, benzyloxy, cyclohexyloxy and tert-butoxy, not all the halogens can simultaneously be chlorine and R.sub.4, R.sub.3 and R.sub.5 are simultaneously equal to H;

Process for preparation of halogenated or pseudohalogenated cyclic

The present invention relates to new fluorinated hexane compounds corresponding to the following general formula (II): ##STR1## in which X'.sub.2, X'.sub.3 and X'.sub.4 are the same or different, and denote a halogen or a pseudohalogen, preferably a halogen, more preferably chlorine and fluorine, with the condition that, when R.sub.1 is hydroxyl, cyano, amido, imido, ethoxy, benzyloxy, cyclohexyloxy and tert-butoxy, not all the halogens can simultaneously be chlorine and R.sub.4, R.sub.3 and R.sub.5 are simultaneously equal to H;

Synthesis intermediates containing a hexane ring and processes for their

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.

Process for preparing halo acetals from enamines

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.

New intermediates, process for their preparation, and their use for the

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.

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Saint Martin du Vivier, France

Jean-Marie Poirier