| 摘要 |
PURPOSE:To obtain the title compound useful for a heat-sensitive recording material as coloring dye by reacting a specific aromatic diketocarboxylic acid with a specific 4-alkoxydiphenylamine derivative. CONSTITUTION:An aromatic diketocarboxylic acid shown by formula I (R<1> and R<2> are 1-9C alkyl or 3-6C cycloalkyl) is made to react with a 4- alkoxydiphenylamine derivative shown by formula II (R<3> is H or anilino); R<4> is H or 1-4C alkyl; R<5> is lower alkyl) (the amount used is preferably 2mols based on 1mol of the compound shown by formula II) in an inert gas atmosphere in the presence of conc. sulfuric acid at 40-100 deg.C for 2-20 hours, added to ice water, filtered, neutralized and washed with toluene to give the objective compound shown by formula III. |
