| 摘要 |
<p>High purity 4,4'-dihydroxydiphenylsulphone is prepd. from phenol and sulphuric acid in high yields, by heating in the presence of solvents such as chlorobenzene, dichlorobenzene, xylene, etc., at 160-200 degrees C. The solvent is gradually distilled away from the reaction system 4,4'-dihydroxydiphenylsulphone formed is deposited and the reaction is continued. The 2,4-dihydroxydiphenylsulphone by produced is isomerized to 4,4'-dihydroxydiphenylsulphone and finally the whole amount of the solvent is distilled away prior to completion of the isomerization 2,4'-dihydroxydiphenylsulphone contained in the reaction prod. is so low that it can be disregarded. 4,4'-dihydroxydiphenylsulphone is produced in yields of >90%.</p> |
