Dominique Laucher

Hydroxylation of phenolic compounds

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.

Oxidation of alkylphenols to hydroxybenzaldehydes

4-methylphenol is oxidized into p-hydroxybenzaldehyde by oxygen or air, in water/acetic acid media, in the presence of catalysts like Pd/C or Pd-Sn/C (66% selectivity for total conversion). The former catalysts are not able to yield ohydroxybenzaldehyde from 2-methylphenol. However, good performances are reach with a Pd-Pt/C catalyst (60% selectivity for total conversion)