反应详情

温度

-78 °C

To a solution of 1-bromo-3,4-difluorobenzene (3.5 g, 18.13 mmol) in dry diethyl ether (25 mL) under nitrogen at −78° C., was added dropwise n-butyllithium (2.5 M in hexane, 7.25 mL, 18.13 mmol). The mixture was stirred for 30 min at −78° C. after which a solution of 1-N-boc-3-pyrrolidinone (3.35 g, 18.13 mmol) in dry diethyl ether (25 mL) was added drop wise. The mixture was stirred at −78° C. for 10 min and then brought to ambient temperature over a period of 2 h. Aqueous sodium carbonate (10%) was added and the mixture was extracted with ethyl acetate (3×50 mL). The combined organic phase was dried (Na2SO4), filtered and evaporated. Purification by flash column chromatography on silica gel (isooctane/ethyl acetate, 4:1 to 1:1) gave the title compound (2.6 g). MS m/z (rel. intensity, 70 eV) 243 (18), 198 (23), 141 (18), 127 (21), 57 (bp).

1. additionwas added drop wise
2. waitbrought to ambient temperature over a period of 2 h
3. extractionthe mixture was extracted with ethyl acetate (3×50 mL)
4. dry with materialThe combined organic phase was dried (Na2SO4)
5. filtrationfiltered
6. customevaporated
7. customPurification by flash column chromatography on silica gel (isooctane/ethyl acetate, 4:1 to 1:1)