反应详情

To acetic anhydride (10 ml) was added dropwise conc. nitric acid (d=1.42, 1.300 ml) during 10 minutes in an ice bath and added one drop of conc. sulfuric acid (96%). To this solution was added a solution of ethyl 4-bromo-2-(trifluoromethyl)phenylcarbamate in acetic anhydride (7 ml)/acetic acid (1 ml) during 30 minutes in an ice bath. After stirring for 2.5 hours, the reaction mixture was poured into ice-water, and the precipitated solid product was filtered. The resultant solid product was purified by silica gel column (120 g, hexane:ethyl acetate=15:1) to give the title compound (2.3265 g, 61%).

1. filtrationthe precipitated solid product was filtered
2. customThe resultant solid product was purified by silica gel column (120 g, hexane:ethyl acetate=15:1)