Ammonia → 3,3'-Diaminobenzophenone

Participants

Reaction Conditions

Reaction Steps

30.7 g (0.1 mol) of this crude chlorodinitrobenzophenone, 0.31 g of 5% Pd/C (a product of Nippon Engelhardt K.K.) and 200 ml of ethanol were charged in a closed glass vessel equipped with a thermometer and a stirrer. While vigorously stirring the mixture at 45±2° C., hydrogen was introduced thereinto and 11.76 l(0.525 mol) of hydrogen was absorbed in 7 hours. The reaction mixture was cooled to 30±2° C. and 11 g of 28% aqueous ammonia was added thereto. Hydrogen was introduced at the same temperature and 3.84 l (0.17 mol) of hydrogen was absorbed in 5 hours. After the completion of the reaction, the temperature of the reaction mixture was raised to 75° to 80° C. The catalyst and contaminants were removed by filtering the reaction mixture with heating. The filtrate was cooled to precipitate 3,3'-diaminobenzophenone as a yellow crystal. The crystal was recovered by filtration, washed with a 50% aqueous ethanol solution, and dried to give 15.3 g (yield 72.2% based on the crude chlorodinitrobenzophenone) of a product with m.p. of 148° to 149.5° C. This product was recrystallized from water to give pure 3,3'-diaminobenzophenone as a light yellow needle crystal with m.p. of 149° to 150° C.

Provenance & Evidence