Pyromellitic dianhydride → Quinoline Yellow

Participants

Reaction Steps

65.4 Parts of pyromellitic acid dianhydride and 61 parts of 3-hydroxy-2-methyl-quinoline-4-carboxylic acid are heated under reflux at 205° in 1000 parts of nitrobenzene for 1 hour, distilling off the water produced by the reaction. The mixture is held at this temperature for 31/2 hours. The mixture is then cooled to 10° and after stirring at this temperature for 1 hour, is filtered and the product is washed in toluene and ethanol. 93 parts of a dark brown quinophthalone intermediate result.

Provenance & Evidence