反应详情

温度

-50 °C

To oxazolidinone 100 (12.1 g, 0.04 mol) in THF (200 ml) at −50° C. was added NaHMDS (48 mL of a 1 M solution in THF). After 30 t-butylbromoaceate (15.6 g, 0.08 mol) was added. The solution was stirred for 4 hours at −50° C. and then warmed to room temperature. After 16 hours a saturated aqueous solution of ammonium chloride was added and the two layers separated. The aqueous phase was extracted with ether and the combined organic phases dried (MgSO4) and concentrated. Flash chromatography (9:1 hexane/EtOAc) gave the product 101 as a white solid 12 g; 72%. [α]D=30.2 (c 1 in CHCl3). 13C NMR (100 MHz; CDCl3) 176.47, 171.24, 152.72, 133.63, 128.87, 125.86, 80.85, 78.88, 55.34, 39.98, 38.77, 38.15, 37.58, 30.60, 28.23, 20.38, 20.13, 14.50, 14.28.

1. temperaturewarmed to room temperature
2. customthe two layers separated
3. extractionThe aqueous phase was extracted with ether
4. dry with materialthe combined organic phases dried (MgSO4)
5. concentrationconcentrated