反应详情

温度

-20 °C

4H,10H-pyrazolo[5,1-c][1,4]benzoxazepine-2-carbaldehyde (0.19 g, 0.887 mmol) in acetonitrile (14 ml) was added to MgBr2 (0.49 g, 2.66 mmol) under N2. After 25 minutes 6-Bromo-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester (0.342 g, 0.888 mmol.) in THF (14 ml) was added. After 15 minutes the reaction was cooled to −20° C. Ten minutes later added Et3N (3eq) and placed reaction in the dark. After 6.5 hours added Ac2O (0.42 ml, 4.45 mmol) and DMAP (0.011 g, 0.0900 mmol). Warmed to 0° C. and placed in freezer overnight. Reaction solution was concentrated and resulting residue was taken up in EtOAc. Washed with 5% citric acid(aq) and saturated NaHCO3(aq). Further washed with water and brine. Dried organics over sodium sulfate and filtered and concentrated. Purified with silica gel prep plates and 1:2 EtOAc/Hexane. Obtained the condensation product (yellow gum/solid). Yield: 0.31 g, 54% yield.

1. customreaction in the dark
2. temperatureWarmed to 0° C.
3. customReaction solution
4. concentrationwas concentrated
5. customresulting residue
6. washWashed with 5% citric acid(aq) and saturated NaHCO3(aq)
7. washFurther washed with water and brine
8. filtrationDried organics over sodium sulfate and filtered
9. concentrationconcentrated
10. customPurified with silica gel prep plates and 1:2 EtOAc/Hexane
11. customObtained the condensation product (yellow gum/solid)