反应详情

温度

-40 °C

To a stirred solution of thionyl chloride (4.1 mL, 56.8 mmol) in acetonitrile (30 mL) cooled to −45° C. is added a solution of tert-butyl (3-hydroxybutan-2-yl)carbamate (4.30 g, 22.7 mmol) in acetonitrile (40 mL) by syringe over 10 min, keeping the internal temperature below −40° C. When the addition is complete, 4-dimethylamino pyridine (277.5 mg, 2.3 mmol) is added followed by the dropwise addition of pyridine (9.2 mL, 113.6 mmol), keeping the temperature below −40° C. The reaction mixture is stirred at −40° C. for 1 h. Ethyl acetate (70 mL) is added to the suspension and the mixture is filtered at −35° C. The solid is washed with EtOAc and the filtrates are combined. Saturated Na2HPO4 solution (40 mL) is added and the mixture is stirred vigorously for 30 min. The organic layer is separated, washed with 1M NaHSO4, dried (MgSO4) and concentrated to afford the title crude compound (4.83 g, 90%) as an oil.

1. customthe internal temperature below −40° C
2. additionWhen the addition
3. customthe temperature below −40° C
4. filtrationthe mixture is filtered at −35° C
5. washThe solid is washed with EtOAc
6. additionSaturated Na2HPO4 solution (40 mL) is added
7. stirringthe mixture is stirred vigorously for 30 min
8. customThe organic layer is separated
9. washwashed with 1M NaHSO4
10. dry with materialdried (MgSO4)
11. concentrationconcentrated