反应详情

N-Benzyl-N-(methoxymethyl)trimethylsilylmethylamine (10.03 g, 40.5 mmol) was added to (S)-4-phenyl-3-[(E)-(3-phenyl-acryloyl)]-oxazolidin-2-one (10.3 g, 35.1 mmol) in toluene (150 mL) at 0° C. and stirred for 20 minutes. Trifluoroacetic acid (9.7 mL) in dichloromethane (125 mL) was added dropwise to the reaction mixture keeping the internal temperature at 0° C. The reaction was stirred at room temperature overnight. The reaction mixture was poured into saturated sodium bicarbonate (200 mL) and extracted with dichloromethane (2×75 mL). The combined organic phases were washed with brine and dried over sodium sulfate. The organic phases were concentrated to give a waxy solid, which was purified by flash silica gel chromatography eluting with ethyl acetate:hexanes (1:9) to give 9.68 g (61%) of (S)-3-((3R,4S)-1-benzyl-4-phenyl-pyrrolidine-3-carbonyl)-4-phenyl-oxazolidin-2-one.

1. customat 0° C
2. stirringThe reaction was stirred at room temperature overnight
3. extractionextracted with dichloromethane (2×75 mL)
4. washThe combined organic phases were washed with brine
5. dry with materialdried over sodium sulfate
6. concentrationThe organic phases were concentrated
7. customto give a waxy solid, which
8. customwas purified by flash silica gel chromatography
9. washeluting with ethyl acetate:hexanes (1:9)