反应详情

温度

100 °C

A mixture of N-α-CBZ-glycine (2.0 g, 9.57 mmol), bromoacetaldehyde dimethyl acetal (2.25 mL, 19.13 mmol) and Cs2CO3 (2.78 g, 3.12 mmol) in 20 mL of anhydrous DMF was stirred at 100° C. for 24 h. After cooling to room temperature, water was added and the mixture was extracted with ethyl acetate (3×80 mL), dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel using 45-50% ethyl acetate/hexanes to give the product 37 (1.74 g, 61%). 1H NMR (400 MHz, CDCl3) δ 3.38 (s, 6H), 3.98 (d, J=5.7 Hz, 2H), 4.12 (d, J=5.3 Hz, 2H), 4.54 (t, J=5.3 Hz, 1H), 5.10 (s, 2H), 5.50 (bs, 1H), 7.32 (m, 5H).

1. temperatureAfter cooling to room temperature
2. extractionthe mixture was extracted with ethyl acetate (3×80 mL)
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was purified by flash chromatography on silica gel using 45-50% ethyl acetate/hexanes