反应详情

温度

45 °C

To a mixture of tert-butyl 6-bromopyridin-2-ylcarbamate (686 mg, 2.51 mmol), K2CO3 (347 mg, 2.51 mmol), (2,2-dimethyltetrahydro-2H-pyran-4-yl)methyl 4-methylbenzenesulfonate (750 mg, 2.51 mmol) in DMF (10 mL) was added carefully NaH (60 wt. %, 141 mg, 3.52 mmol) in portions [Caution: gas development!]. The resulting mixture was stirred at about 45° C. for 4 hr. The mixture was warmed to ambient temperature and was diluted with EtOAc (˜50 mL) and saturated aqueous NaHCO3. The organic layer was separated, washed with saturated aqueous NaHCO3 solution (1×), dried over Na2SO4, filtered off and concentrated in vacuo. The resulting residue was purified by column chromatography [SiO2, 40 g, 25 min, EtOAc/heptane=0/100 to 25/75 over 25 min] providing (R/S)-tert-butyl 6-bromopyridin-2-yl((2,2-dimethyltetrahydro-2H-pyran-4-yl)methyl)carbamate as highly viscous, colorless oil. Yield: 723 mg. LCMS (m/z): 344.9 {loss of tert Bu-group}/(399.0).[M+H]+; Retention time=1.22 min.

1. temperatureThe mixture was warmed to ambient temperature
2. customThe organic layer was separated
3. washwashed with saturated aqueous NaHCO3 solution (1×)
4. dry with materialdried over Na2SO4
5. filtrationfiltered off
6. concentrationconcentrated in vacuo
7. customThe resulting residue was purified by column chromatography [SiO2, 40 g, 25 min, EtOAc/heptane=0/100 to 25/75 over 25 min]