| 摘要 |
<p>1385474 Purifying diarylamines IMPERIAL CHEMICAL -INDUSTRIES Iad 22 March 1972 [7 April 1971] 8941/71 Heading C2C The amount of primary arylamine impurity in a secondary diarylamine is reduced by heating the diarylamine with an organic acid or functional derivative thereof which will react with a primary amine to form an amide or imide. The preferred acids are alkyl, alkenyl, cycloalkyl and aromatic mono-, di- and polycarboxylic acids and the functional derivative is preferably an acid anhydride, acid chloride, ester or amide.</p> |
