反应详情

温度

75 °C

2-Amino-5-bromopyridine-3-sulfonyl chloride (100 mg, 0.37 mmol) was taken into 1:1 aqueous dioxane (3 mL) and the mixture was basified to pH 14 by drop wise addition of 50% aqueous sodium hydroxide solution. The mixture was warmed to 75° C. for 0.5 h then cooled to room temperature and concentrated. The residue was taken into water (2 mL) and carefully acidified to pH 1-2 by concentrated aqueous hydrochloric acid addition and cooled to 0° C. After 1 h at 0° C. the crystalline solid obtained was collected by filtration and dried to give 2-amino-5-bromopyridine-3-sulfonic acid as a solid. 1H NMR (DMSO-d6): 8.24 (d, 1H), 8.06 (d, 1H). MS (EI) for C5H5N2SO3Br: 253, 255 (MH+, Br pattern).

1. temperaturethen cooled to room temperature
2. concentrationconcentrated
3. additioncarefully acidified to pH 1-2 by concentrated aqueous hydrochloric acid addition
4. temperaturecooled to 0° C
5. customAfter 1 h at 0° C. the crystalline solid obtained
6. filtrationwas collected by filtration
7. customdried