PROCESS FOR THE PREPARATION OF PURE, AROMATIC O-HYDROXY-CARBOXYLIC ACID ARYL AMIDES

摘要

Process for the preparation of pure aromatic o-hydroxy-carboxylic acid aryl amides by condensing an aromatic o-hydroxy-carboxylic acid with an aryl amine in the presence of phosphorus chlorides in an organic solvent or diluent, which process comprises treating the reaction mixture or the reaction product with 1 to 25 %, calculated on the weight of the reaction product, of an aliphatic amino-polycarboxylic acid as chelate forming agent. It is not necessary to purify the products, because they are obtained in such a pure form that they can be used directly as coupling components for azo pigments.