Rhone-Poulenc Chimie

Dominique Laucher

Michel Costantini

Eric Fache

Phenolic compounds, e.g., the phenols and phenol ethers, are selectively hydroxylated whereby the amounts of the final product para isomer are enhanced, for example in favor of hydroquinone versus pyrocatechol in the event of the hydroxylation of phenol, by reacting such phenolic compounds with hydrogen peroxide, advantageously in a polar, aprotic, organic solvent reaction medium, in the presence of a catalytically effective amount of a sulfonated polymer and a cocatalytically effective amount of an aromatic ketone compound.

Hydroxylation of phenolic compounds

Aromatic compounds bearing oxidizable alkyl substituents, e.g., alkoxylated and/or hydroxylated such substrates, notably the phenolics/cresols, are selectively oxidized, e.g., into hydroxybenzaldehydes, by reacting same with appropriate oxidizing agents, in an aqueous reaction medium, in the presence of a catalytically effective amount of a solid, palladium-containing oxidation catalyst (optionally containing a cocatalytically effective amount of tin, germanium, tellurium and/or copper).

Oxidation of aromatic compounds substituted by oxidizable alkyl moieties

The present invention relates to a process for monohydroxylation of phenolic compounds which allows an increase in the amount of para isomer. The invention relates to a process for monohydroxylation of a phenolic compound having a hydrogen atom in the para position to the hydroxyl group, for the purpose of obtaining a dihydroxylated aromatic compound by reacting the initial phenolic compound with hydrogen peroxide in the presence of an effective amount of a strong acid and of a ketonic compound, said process being characterized by the fact that the reaction is carried out in the presence of an effective amount of a polar aprotic organic solvent with a basicity such that it has a 'donor number' below 25.

Process for monohydroxylation of phenolic compounds

The phenols/phenol ethers are hydroxylated by reaction with hydrogen peroxide, in the presence of a catalytically effective amount of (a) at least one alkali metal or alkaline earth metal salt of a protonic acid having a pKa in water of less than -0.1 and (b) a free protonic acid.

Hydroxylation of phenols/phenol ethers

Dialkoxybutenes are selectively prepared in high yields by reacting 1,3-butadiene with an alcohol in the presence of oxygen and a catalytically effective amount of solid particulates which comprise a catalytically active phase deposited onto particles of a support therefor, such catalytically active phase comprising at least one Group VIII noble metal first component, at least one tellurium, selenium and/or sulfur second component, and, optionally, at least one bismuth, antimony, copper and/or tin third component.

Preparation of dialkoxybutenes

The phenols and phenol ethers are hydroxylated by reacting such phenols/phenol ethers with hydrogen peroxide, in the presence of (a) a catalytically effective amount of an alkali metal or alkaline earth metal salt of at least one protonic acid having a pKa in water of less than -0.1, and (b) an effective amount of at least one phosphorus oxyacid.

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Lyons, France

Dominique Laucher