反应详情

温度

10 °C

Compound 209A (133 mg, 0.645 mmol) was dissolved in 1 mL AcOH and the resulting solution was cooled to 10° C. At this temperature, 80.0 μL (2.00 mmol) of red fuming HNO3 was added and stirring was continued for 15 min before the reaction was quenched by the addition of crushed ice. The aqueous layer was extracted with CH2Cl2 and the combined organic phases were dried over MgSO4 and concentrated in vacuo. The resulting residue was dissolved in 3 mL EtOH, heated to reflux and treated with 0.5 mL of 40% aqueous NaOH solution. Stirring was continued for 15 min before the reaction was cooled and diluted with H2O. The aqueous layer was extracted with CH2Cl2 and the combined organic phases were dried over MgSO4 and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel, eluting with 40 to 70% EtOAc in hexane to afford 36 mg (0.17 mmol, 27%) of compound 209B as a yellow solid.

1. customwas quenched by the addition of crushed ice
2. extractionThe aqueous layer was extracted with CH2Cl2
3. dry with materialthe combined organic phases were dried over MgSO4
4. concentrationconcentrated in vacuo
5. dissolutionThe resulting residue was dissolved in 3 mL EtOH
6. temperatureheated
7. temperatureto reflux
8. additiontreated with 0.5 mL of 40% aqueous NaOH solution
9. stirringStirring
10. waitwas continued for 15 min before the reaction
11. temperaturewas cooled
12. additiondiluted with H2O
13. extractionThe aqueous layer was extracted with CH2Cl2
14. dry with materialthe combined organic phases were dried over MgSO4
15. concentrationconcentrated in vacuo
16. customThe resulting residue was purified by flash chromatography on silica gel
17. washeluting with 40 to 70% EtOAc in hexane