| 摘要 |
<p>The present invention relates to a process for the preparation of tetrafluorophthalic acid and/or tetrafluorophthalic anhydride, by reacting a compound of the general formula <IMAGE> in which X represents a radical <IMAGE> which is optionally monosubstituted or polysubstituted in the aromatic nucleus by fluorine and/or chlorine and/or alkyl groups having 1 to 4 carbon atoms, or a radical <IMAGE> in which R1 and R2 are identical or different and denote a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkyl-CO group having 1 to 6 carbon atoms in the alkyl radical, an aryl or aryl-CO group, each of which is optionally monosubstituted or polysubstituted in the aromatic ring by fluorine and/or chlorine and/or alkyl groups having 1 to 4 carbon atoms, or R1 and R2 together form a radical of the general formula <IMAGE> in which R3 is a hydrogen atom, a chlorine atom or a fluorine atom, with water, subsequently removing any remaining water by azeotropic distillation, or extracting tetrafluorophthalic acid and/or its anhydride using a water-insoluble solvent or solvent mixture.</p> |
