反应详情

To a solution of 2-bromo-3-nitrobenzoic acid (500 mg, 2.03 mmol) in DMF (3 mL) was added tert-butylamine (0.22 mL, 2.04 mmol), 1,1′-dimethyltriethylamine (0.71 mL, 4.1 mmol) and (1H-benzo[d][1,2,3]triazol-1-yloxy)tripyrrolidin-1-ylphosphonium hexafluorophosphate(V) (1.27 g, 2.44 mmol). The resulting mixture was stirred at rt for 2 h. The reaction mixture was diluted with EtOAc, washed with water, brine, dried over magnesium sulfate and concentrated in vacuo. The residue was purified by flash chromatography on silica gel using 0 to 100% gradient of EtOAC:DCM (1:1) in DCM as eluent to give 2-bromo-N-tert-butyl-3-nitrobenzamide: 1H NMR (400 MHz, CDCl3) δ 7.74 (1H, dd, J=8.0, 4.0 Hz), 7.62 (1H, d, J=8.0 Hz), 7.51 (1H, t, J=8.0 Hz), 5.62 (1H, br), 1.52 (9H, s); LC-MS (ESI) m/z 301.0 [M+H]+.

1. washwashed with water, brine
2. dry with materialdried over magnesium sulfate
3. concentrationconcentrated in vacuo
4. customThe residue was purified by flash chromatography on silica gel using 0 to 100% gradient of EtOAC