Rhone-Poulenc Industries

Rhone-Poulenc S.a.

Rhone-Poulenc Chimie

Rhone-Poulenc-Textile

Michel Jouffret

Michel Costantini

Adrien Dromard

Guy Lartigau

Pierre-Etienne Bost

Roland Nantermet

Lucien Billet

Michel Constantini

Jean Claude Brunie

Noel Crenne

Pierre Bost

Phenolic compounds, e.g., phenol, are hydroxylated, preponderantly into the para-isomer, e.g., hydroquinone, by reaction with hydrogen peroxide in the presence of an effective amount of a strong acid and a catalytically effective amount of a keto compound having the formula (II): ##STR1## in which R.sub.1 and R.sub.2, which may be identical or different, are each a hydrogen atom or an electron-donating group; n.sub.1 and n.sub.2, which may be identical or different, are numbers equal to 0, 1, 2 or 3, with the proviso that the two carbon atoms located at the .alpha.-position with respect to the two carbon atoms bearing the --CO group may be bonded together via a valence bond or via a --CH.sub.2 -- group, thereby forming a keto-containing ring member which may either be saturated or unsaturated.

Hydroxylation of phenolic compounds

Aromatic hydrocarbons and particularly phenols and phenol ethers can be hydroxylated by reacting the aromatic compound with hydrogen peroxide in a reaction medium comprising trifluoromethanesulfonic acid. High yields of hydroxylated aromatic compounds are obtained by this process which avoids the use of extremely corrosive and difficult to handle agents. Phenol is hydroxylated predominantly to hydroquinone by this process.

Process for the hydroxylation of aromatic compounds

Epoxides, e.g., ethylene and propylene oxides, are prepared from lower alkane-1,2-diols by dehydrating the corresponding diol, in liquid phase, under at least atmospheric pressure, and in the presence of at least one high-boiling organic carboxylic acid and at least one alkali metal or alkaline earth metal carboxylate.

Production of epoxides from lower alkane-1,2-diols

Aromatic compounds of the general formula ##STR1## in which R and R.sub.o represents a hydrogen atom or an alkyl radical of 1 to 4 carbon atoms are hydroxylated by reaction with hydrogen peroxide in the presence of a catalytic amount of a strong acid and the reaction is carried out in the presence of an activator which is a juxtanuclear aromatic aldehyde or derivative thereof selected from an acetal or a benzhydrol.

Hydroxylation of aromatic compounds

p-Benzoquinone is prepared by oxidizing phenol with molecular oxygen or with a gas in which oxygen is present, in the liquid phase, in the presence of cuprous or cupric ions. The improvement resides in carrying out the reaction in the presence of a metal, in the metallic form, which is selected from the group consisting of nickel, iron, tin, cobalt, chromium, molybdenum, magnesium and copper. The resultant p-benzoquinone is useful as an industrial source of hydroquinone, which is employed in photography.

Process for the preparation of para-benzoquinone

4-Hydroxy-2,4,6-trimethyl-cyclohexa-2,5-dien-1-one ['mesitylquinol'] is prepared by oxidizing 2,4,6-trimethyl phenol ['mesitol'] with either molecular oxygen or an oxygen containing gas, in the simultaneous presence of (i) a cobalt/Schiff base complex, (ii) an amine, phosphine and/or organic phosphite co-catalyst, and, optionally, (iii) an alkali metal base.

Preparation of 4-hydroxy-2,4,6-trimethyl-cyclohexa-2,5-diene-1-one

Trimethyl-p-benzoquinone is produced in good yields quickly by oxidation of 2,3,6-trimethyl-phenol in the presence of a complex cobalt salt of the general formula: ##STR1## in which: R.sup.1 and R.sup.2, which can be identical or different, each represents an alkoxy radical possessing 1 to 4 carbon atoms, and R.sup.3 represents a divalent hydrocarbon radical possessing 2 to 15 carbon atoms, in an inert organic solvent medium.

Process for the preparation of trimethyl-p-benzoquinone

3,5,5-Trimethyl-cyclohex-2-ene-1,4-dione is prepared by a liquid phase oxidation of .beta.-isophorone using carbon black as catalyst in the presence of a base.

Process for the preparation of 3,5,5-trimethyl-cyclohex-2-ene-1,4-dione

The rate of palladium catalyzed deperoxidation of cyclohexyl hydroperoxide to form hex-2-enal is increased by carrying out the deperoxidation using an aqueous solution containing both a palladium derivative and a derivative of divalent iron.

Process for the preparation of hex-2-enal

A process for the oxidation of .beta.-ethylenically unsaturated ketones, especially .beta.-isophorone, is provided whereby the ketone is oxidized with a source of molecular oxygen in an organic liquid solvent in the presence of a base and certain chelate catalysts of cobalt or manganese as defined.

Process for the oxidation of .beta.-isophorone

Process for splitting primary alkylaromatic hydroperoxides to yield phenolic products is described which consists of reacting the hydroperoxide with a catalytic amount of a compound with an acid reaction, in an organic solvent medium, the characteristic feature being that the splitting medium is a mixture consisting of:

Process for splitting alkylaromatic hydroperoxides into phenolic

Cycloaliphatic hydroperoxides are extracted from the reaction mixtures obtained by oxidising the corresponding cycloaliphatic hydrocarbons with the aid of a polar aprotic solvent which is not miscible with the hydrocarbon, said solvent being a polymethylenesulphone or an alkylene glycol carbonate, the alkylene portion containing 2 to 4 carbon atoms.

Process for extracting cycloaliphatic hydroperoxides

Aromatic compounds of formula ##SPC1## In which R and R.sup.1 are independently hydrogen or C.sub.1 - C.sub.4 alkyl are hydroxylated with hydrogen peroxide and a phosphorus compounds, which is a phosphoric acid, ester thereof, halogenophosphoric acid, ester thereof, phosphorus pentoxide, phosphorus halide or oxyhalide, in the absence of acid of pK &lt; -0.1.

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Francheville le bas, France

Michel Jouffret