反应详情

To a mixture of methyl 5-bromo-2-hydroxybenzoate (150 g, 0.65 mol) in concentrated H2SO4 (320 mL) below 0° C. was added dropwise a mixture of concentrated HNO3 (69.2 g, 0.71 mol) and concentrated H2SO4 (97 mL) with stirring below 5° C. After the addition, the mixture was stirred at this temperature for 3 hr. The reaction mixture was poured into crash ice and the precipitate was collected, washed with cold water, hot ethanol and dried to give methyl 5-bromo-2-hydroxy-3-nitrobenzoate (153 g, yield 85%). 1H-NMR (400 MHz, CDCl3-d) δ 4.04 (s, 3H), 8.25 (d, J=2.4 Hz, 1H), 8.28 (d, J=2.4 Hz, 1H), 11.92 (s, 1H); LC-MS (ESI) m/z 278 [M+1]+.

1. additionwas added dropwise
2. additionAfter the addition
3. stirringthe mixture was stirred at this temperature for 3 hr
4. additionThe reaction mixture was poured into crash ice
5. customthe precipitate was collected
6. washwashed with cold water, hot ethanol
7. customdried