反应详情

29 g (101 mmol) of 5-bromo-2-(2-nitro-vinylamino)-benzoic acid (Example 1a) and 11.9 g (121 mmol) of potassium acetate in 129 ml (152 mmol) of acetic anhydride are stirred for 1.5 h at 120° C. The precipitate is filtered off and washed with acetic acid until the filtrate is colorless, then is washed with H2O and dried in vacuo to give the title compound. ES-MS: 269, 271 (M+H)+, Br pattern; analytical HPLC: tret=2.70 min (Grad 1).

1. filtrationThe precipitate is filtered off
2. washwashed with acetic acid until the filtrate
3. washis washed with H2O
4. customdried in vacuo