Process for the preparation of aromatic hydroxy compounds
AssigneeCiba-Geigy Corporation
InventorsRolf Muller, Maurice Grelat
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Abstract
The invention relates to a process for the preparation of aromatic hydroxy compounds, starting from the corresponding halogenated aromatic compounds and replacing the halogen atom or atoms by the hydroxyl group. The process comprises converting the halogenated aromatic compound into the hydroxy compound by treatment with concentrated sulfuric acid, with the addition of an aldehyde and at elevated temperature. The aromatic hydroxy compounds are used as intermediates, for example for the manufacture of disperse and vat dyes.
Claims8
A process for the preparation of a hydroxy substituted anthraquinone, naphthoquinone or phenol compound, starting from a corresponding halogenated compound and replacing the halogen atom or atoms by a hydroxyl group, which process comprises reacting a halogenated anthraquinone, naphthoquinone or phenol compound with concentrated sulfuric acid, with the addition of an aldehyde, at a temperature of 50.degree. to 200.degree. C.
Dependencies are inferred from the claim text.