反应详情

To a solution of (6-bromo-5-fluoro-pyridin-2-yl)-carbamic acid tert-butyl ester (1.43 g, 4.91 mmol) in DCM (25 mL) was added TFA (3.78 mL, 49.1 mmol, Eq: 10.0). The mixture was stirred at room temperature for 2 h, after which it was concentrated in vacuo, and redissolved in EtOAc. The organic layer was washed with sat. aq. NaHCO3 followed by water and brine. The resulting organic layer was concentrated on to silica gel and chromatographed (10% to 40% EtOAc/hexanes) to give 6-bromo-5-fluoro-pyridin-2-ylamine (850 mg, 91%). 1H NMR (400 MHz, CHLOROFORM-d6) δ ppm 7.23 (dd, J=8.6, 7.5 Hz, 1H), 6.41 (dd, J=8.6, 2.6 Hz, 1H), 4.40 (br. s, 2H).

1. concentrationafter which it was concentrated in vacuo
2. dissolutionredissolved in EtOAc
3. washThe organic layer was washed with sat. aq. NaHCO3
4. concentrationThe resulting organic layer was concentrated on to silica gel
5. customchromatographed (10% to 40% EtOAc/hexanes)