4-Aminophenol → 2-Anthracenesulfonic acid, 1-amino-9,10-dihydro-4-[(4-hydroxyphenyl)amino]-9,10-dioxo-

Participants

Reaction Conditions

Reaction Steps

38.2 parts of 1-amino-4-bromo-2-sulfoanthraquinone (bromamine acid) are condensed in an aqueous suspension with 12.7 parts of 4-aminophenol with the addition of 1 part of copper(II) sulfate at a pH of 8.5 and a temperature of 70° C. over a period of 1 to 2 hours. This results in a dark blue solution. After cooling to 20°-25° C., the reaction mixture is acidified until reaching a pH of about 1, stirred at 60° C. for about 1 h, salted out with sodium chloride, and the dye chromophore 4-(4'-hydroxyphenyl)amino-1-amino-2-sulfoanthraquinone is isolated by suction filtration.

Provenance & Evidence