反应详情

A stirred suspension of 2,5-diaminonitrobenzene (60 g.) in a solution of sodium bicarbonate (49.4 g) in water (780 ml) at 10° C. was treated dropwise with isopropyl chloroformate (48 g) and the mixture was stirred at room temperature for 3 hours. The crude brown solid was filtered off, washed well with water and dried to give 4-isopropoxycarbonylamino-2-nitroaniline (90.0 g), m.p. 158°-160° C., which was used in the next stage of the synthesis without further purification being necessary. Recrystallization of a sample from toluene gave pure 4-isopropoxycarbonylamino-2-nitroaniline, m.p. 161°-163° C.

1. filtrationThe crude brown solid was filtered off
2. washwashed well with water
3. customdried