反应详情

Into a solution of 4,5-difluoro-2-nitroaniline (3.7 g) in acetic acid (27 ml) was added bromine (6.8 g) dropwise at 50° to 56° C. and stirred for 2.5 hours. The reaction mixture was poured into ice water (60 ml) and the resulting precipitate was collected by filtration and washed with water sufficiently to give the title compound (4.7 g) as yellow prisms, mp 105° C.

1. filtrationthe resulting precipitate was collected by filtration
2. washwashed with water sufficiently