Acetic Anhydride → 2-(Tert-butoxycarbonylamino)-1,1-dimethylethyl acetate

温度

0 °C

2-Hydroxy-2-methylpropylcarbamic acid tert-butylester (510 mg, 2.69 mmol) was dissolved in dichloromethane (7 ml). The solution was cooled to 0° C. Ethyldiisopropylamine (0.70 ml, 4.04 mmol), 4-dimethylaminopyridine (33 mg, 0.27 mmol), and acetic acid anhydride (0.33 ml, 3.50 mmol) were added successively. The reaction mixture was stirred for 16 h, while slowly warming up to room temperature. It was diluted with ethyl acetate (30 ml) and extracted with 1N hydrochloric acid (30 ml). The aqueous phase was extracted with ethyl acetate (2×20 ml). The combined organic layers were washed with saturated sodium hydrogen carbonate solution (50 ml) and dried over magnesium sulfate. The solvent was removed in vacuo. The crude product was purified by flash chromatography on silica (100 g), using ethyl acetatelheptane (1:2) as eluent, to give 550 mg of 2-(tert-butoxycarbonylamino)-1,1-dimethylethyl acetate.

1. temperaturewhile slowly warming up to room temperature
2. extractionextracted with 1N hydrochloric acid (30 ml)
3. extractionThe aqueous phase was extracted with ethyl acetate (2×20 ml)
4. washThe combined organic layers were washed with saturated sodium hydrogen carbonate solution (50 ml)
5. dry with materialdried over magnesium sulfate
6. customThe solvent was removed in vacuo
7. customThe crude product was purified by flash chromatography on silica (100 g)

ORDレコード

ord-2d772a32bf1841a6aa1099a2c51ee119

出典データセット

uspto-grants-2005_09

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06939880B2