反应详情

温度

40 °C

5.00 g (37.3 mmol) of 5-hydroxyindazole are dissolved in 40 ml of anhydrous DMF. 5.93 g (37.3 mmol) of 3,4-difluoronitrobenzene and 5.15 g (37.3 mmol) of potassium carbonate are added, and the mixture is stirred at 40° C. overnight. For work-up, the mixture is filtered off with suction through kieselguhr, diluted with water and extracted three times with ethyl acetate. The combined organic phases are washed 1× with saturated aqueous sodium chloride solution, dried over sodium sulfate and concentrated using a rotary evaporator. The residue is chromatographed twice on silica gel using cyclohexane/ethyl acetate 3:1→1:1→1:2 and then purified by preparative HPLC.

1. filtrationFor work-up, the mixture is filtered off with suction through kieselguhr
2. additiondiluted with water
3. extractionextracted three times with ethyl acetate
4. washThe combined organic phases are washed 1× with saturated aqueous sodium chloride solution
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated
7. customa rotary evaporator
8. customThe residue is chromatographed twice on silica gel
9. custompurified by preparative HPLC