| abstract |
PURPOSE:To obtain the title compound by diazotizing 4-amino-5- trifluoromethylphenol or an alkyl ester thereof in the presence of a complex of pyridinepolyhydrogen fluoride and further carrying out dediazotization and fluorination by light irradiation. CONSTITUTION:4-Amino-5-trifluoromethylphenol or an alkyl ester thereof as a raw material is diazotized with a compound such as NaNO2, etc., in the presence of a complex of pyridinepolyhydrogen fluoride or an acid (e.g., hydrofluoric acid, sulfuric acid, acetic acid or tetrafluoroboric acid) except the complex and the reaction product is irradiated with light rays in the presence of the complex, subjected to dediazotization and fluorination to give 4-fluoro-5- trifluoromethylphenol in high yield. The title compound is useful as a raw material for producing herbicides. |