摘要 |
<p>PT--77066 A New biphenyl cpds. are made by reacting a reactive deriv. of 2-hydroxy 5-(2,4-difluoro phenyl) benzoic acid (I) with a substd. aniline (II) or its salt, in a solvent. The OH gp. in (I) is protected, pref. by acetylation, and the protective gp. removed after reaction by hydrolyte with alkali. (I) is pref. the anhydride, ester (esp. methyl ester) or acid halide (esp. chloride). - (II) is pref. a xylidene (esp. 2,6-dimethyl aniline) or an acetoxy-aniline (esp. 4-acetoxy aniline). The solvent is pref. an aromatic or alicyclic 6-12C hydrocarbon a halogenated lower hydrocarbon, a dialkylamide, a tert. amide or binary mixt. of these, and reaction is at -20 to 100 deg.C.</p> |