反应详情

To a solution of 2-amino-4-trifluoromethylpyridine (10.0 g, 62.1 mmol) in chloroform (200 mL) was added N-bromosuccinimide (12.0 g, 67.4 mmol). The solution was stirred in the dark for 2 hours, at which time it was added to CH2Cl2 (200 mL) and 1N NaOH (200 mL). Upon mixing, the layers were separated and the organic layer was washed with NaCl(sat.) (100 mL), dried over Na2SO4, filtered and concentrated. The crude material was purified by SiO2 chromatography (0-5% EtOAc/CH2Cl2) yielding 12.0 g (80%) of 5-bromo-4-(trifluoromethyl)-2-pyridylamine LCMS (m/z): 241/243 (MH+). 1H NMR (CDCl3): δ 8.28 (s, 1H), 6.77 (s, 1H), 4.78 (bs, 2H).

1. additionUpon mixing
2. customthe layers were separated
3. washthe organic layer was washed with NaCl(sat.) (100 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe crude material was purified by SiO2 chromatography (0-5% EtOAc/CH2Cl2)