反应详情

温度

0 °C

To a solution of tert-butyl(S)-(1-(3-acetyl-5-chloropyridin-2-yl)-2-methylpropyl)carbamate (62.3 mg, 191 μmol) in EtOH (1 mL) at 0° C. was added sodium borohydride (7.2 mg, 191 μmol) as a solid. The mixture was stirred at 0° C. for 90 min, then it was quenched with saturated aqueous ammonium chloride (10 mL). The mixture was extracted with EtOAc (20 mL), then the organic phase was washed with brine (10 mL), dried over anhydrous MgSO4, filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography (eluting with 10% EtOAc in hexanes, gradient to 100%) to afford 53.4 mg of tert-butyl((1S)-1-(5-chloro-3-(1-hydroxyethyl)pyridin-2-yl)-2-methylpropyl)carbamate (85% yield). LC-MS tR=1.01 min in 1 min chromatography, MS (ESI) m/z 329.4 [M+H]+. 1H NMR (CDCl3, 400 MHz, mixture of diastereomers): δ 8.44 (d, J=2.4 Hz, 0.3H), 8.41 (d, J=2.4 Hz, 0.7H), 7.86 (d, J=2.4 Hz, 0.7H), 7.77 (d, J=2.4 Hz, 0.3H), 5.44 (d, J=9.6 Hz, 0.7H), 5.31 (m, 0.7H), 5.23 (m, 0.7H), 4.73 (t, J=8.8 Hz, 0.3H), 4.63 (t, J=9.6 Hz, 0.3H), 4.56 (s, 0.3H), 2.18-2.12 (m, 0.3H), 2.08-2.00 (m, 0.7H), 1.56 (d, J=6.8 Hz, 0.9H), 1.52 (d, J=6.8 Hz, 2.1H), 1.40 (s, 9H), 1.11 (d, J=6.8 Hz, 0.9H), 1.00 (d, J=6.8 Hz, 2.1H), 0.80 (d, J=6.8 Hz, 2.1H), 0.69 (d, J=6.8 Hz, 0.9H).

1. customit was quenched with saturated aqueous ammonium chloride (10 mL)
2. extractionThe mixture was extracted with EtOAc (20 mL)
3. washthe organic phase was washed with brine (10 mL)
4. dry with materialdried over anhydrous MgSO4
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel chromatography (eluting with 10% EtOAc in hexanes, gradient to 100%)