反应详情

1.3 g (0.00526 mol) of 6-bromo-4-nitropyridine-2-carboxylic acid were dissolved in 10 ml of dimethylformamide, treated at 5° C. with 0.94 g (0.0058 mol) of 1,1-carbonyldiimidazole and subsequently stirred at room temperature for 3 hrs. Then, 40 ml of 25% NH4OH in water was added thereto and the mixture was stirred at room temperature for 1 hr. The reaction mixture was partitioned in water and dichloromethane and the organic phase was washed with water and sat. sodium chloride solution, dried over MgSO4 and concentrated. The residue was chromatographed on silica gel with ethyl acetate/hexane 1:1. There were obtained 1.1 g (85%) of 6-bromo-4-nitropyridine-2-carboxamide as white crystals; m.p.: 179-180° C.

1. stirringthe mixture was stirred at room temperature for 1 hr
2. customThe reaction mixture was partitioned in water
3. washdichloromethane and the organic phase was washed with water and sat. sodium chloride solution
4. dry with materialdried over MgSO4
5. concentrationconcentrated
6. customThe residue was chromatographed on silica gel with ethyl acetate/hexane 1:1