反应详情

To a solution of 3-(benzyloxy)-6-bromo-N-(4-fluorobenzyl)picolinamide (50 mg, 0.11 mmol) in CH2Cl2 (5 mL) was added BBr3 (1.5 mL) dropwise at −78° C. under N2. The mixture was allowed to room temperature and stirred for another 12 hours. Then CH3OH was added and the mixture was adjusted to pH=7 by saturated K2CO3. The mixture was extracted with EtOAc and the combined organic phase was washed with brine, dried over Na2SO4 and concentrated. The residue was purified by prep-TLC (PE:EtOAc=5:1) to afford the product of 6-bromo-N-(4-fluorobenzyl)-3-hydroxypicolinamide (20 mg, yield: 57%). 1H-NMR (CDCl3, 400 MHz) δ 12.04 (s, 1H), 8.02 (s, 1H), 7.39 (d, J=8.8 Hz, 1H), 7.24˜7.28 (m, 2H), 7.15 (d, J=8.8 Hz, 1H), 6.96˜7.00 (m, 2H), 4.52 (d, J=6.4 Hz, 2H). MS (M+H)+: 325/327.

1. customwas allowed to room temperature
2. extractionThe mixture was extracted with EtOAc
3. washthe combined organic phase was washed with brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated
6. customThe residue was purified by prep-TLC (PE:EtOAc=5:1)