反应详情

温度

0 °C

Diethylaniline (0.33 μL, 2.1 μmol, 1.1 equiv) and 4-methoxyphenyl chloroformate (0.85 μL, 5.7 μmol, 3.0 equiv) were added separately, each in one portion, to a stirred solution of the amine (1.0 mg, 1.9 μmol, 1 equiv) in dichloromethane (0.15 mL) at 0° C. under an argon atmosphere. The reaction mixture was stirred at 0° C. for 40 min, then was quenched by the addition of a 1:1 mixture of water and saturated aqueous sodium hydrogen carbonate solution (3 mL). The mixture was extracted with ethyl acetate (2×10 mL) and the combined organic layer was washed with a 1:1 mixture of brine solution and saturated aqueous sodium hydrogen carbonate solution (5 mL). The organic layer was dried over sodium sulfate and concentrated in vacuo to leave a colorless oil. Purification by flash column chromatography (50%→70% ethyl acetate-hexanes) gave the carbamic acid 4-methoxyphenyl ester derivative (0.9 mg, 70%) as a white solid.

1. customat 0° C.
2. customwas quenched by the addition of a 1:1 mixture of water and saturated aqueous sodium hydrogen carbonate solution (3 mL)
3. extractionThe mixture was extracted with ethyl acetate (2×10 mL)
4. washthe combined organic layer was washed with a 1:1 mixture of brine solution and saturated aqueous sodium hydrogen carbonate solution (5 mL)
5. dry with materialThe organic layer was dried over sodium sulfate
6. concentrationconcentrated in vacuo
7. customto leave a colorless oil
8. customPurification by flash column chromatography (50%→70% ethyl acetate-hexanes)