反应详情

温度

20 °C

A mixture of Intermediate 35 (1.0 g, 3.8 mmol) and N-bromosuccinimide (1.49 g, 8.4 mmol) in carbon tetrachloride (35 ml) was heated at reflux for 3 hours. The reaction mixture was cooled in an ice-bath and the precipitate filtered. The filtrate was concentrated in vacuo and the residue dissolved in tetrahydrofuran (12.5 ml). Water (3.5 ml) and saturated sodium carbonate solution (3 ml) were added and the mixture stirred at 20° C. for 18 hours. The reaction was diluted with water and extracted with ethyl acetate. The combined organic phases were dried Na2SO4) and evaporated in vacuo. The residue was purified on an SPE cartridge (silica, 20 g) eluting with dichloromethane, chloroform, then chloroform:methanol (99:1, 49:1, 19:1 then 9:1). Appropriate fractions were combined and evaporated in vacuo to afford Intermediate 36 as an off-white solid (0.45 g). LCMS showed MH++236, TRET=2.46 min.

1. temperaturewas heated
2. temperatureat reflux for 3 hours
3. temperatureThe reaction mixture was cooled in an ice-bath
4. filtrationthe precipitate filtered
5. concentrationThe filtrate was concentrated in vacuo
6. dissolutionthe residue dissolved in tetrahydrofuran (12.5 ml)
7. additionWater (3.5 ml) and saturated sodium carbonate solution (3 ml) were added
8. additionThe reaction was diluted with water
9. extractionextracted with ethyl acetate
10. customevaporated in vacuo
11. customThe residue was purified on an SPE cartridge (silica, 20 g)
12. washeluting with dichloromethane, chloroform
13. customevaporated in vacuo