Formaldehyde → 9,10-Anthracenedione, 1-amino-2-chloro-4-hydroxy-

Participants

Reaction Conditions

Reaction Steps

A stirred reactor is charged with 184 parts of sulfuric acid monohydrate and 4.8 parts (1 equivalent) of paraformaldehyde are added, with stirring, over about 15 minutes. Stirring is continued until a solution is obtained. This solution is then heated to 60°-65° C. and 46.5 parts of 98% 1-amino-2,4-dichloroanthraquinone are added. The reaction mixture is heated for 1 hour to 110° C. and this temperature is maintained for 3 hours. The mixture is cooled to 100° C. and 870 parts of water are added. The resultant suspension is heated to 90°-95° C. and stirred for 2 hours at this temperature, then cooled and filtered. The filter cake is washed with hot water and the product is dried in vacuo at 80°-90° C., affording 43.3 parts (95% yield) of 1-amino-2-chloro-4-hydroxyanthraquinone. Rf =0.29 (eluant: concentrated formic acid, saturated with 1-bromonaphthalene).

Provenance & Evidence