反应详情

A stirred mixture of 7-amino-3-(4-chlorophenyl)-8-hydroxy-2-isopropyl-chromen-4-one (1.1 g, 3.35 mmol) and sodium formate (0.23 g, 3.35 mmol) in formic acid (50 ml) is heated under reflux for 2 h. After cooling to room temperature, the reaction mixture is poured into ice/water (300 ml) with stirring. The resulting aqueous suspension is washed with ethyl acetate (2×100 ml). The combined organic layers are washed with water (3×100 ml) and brine (100 ml), dried (magnesium sulfate) and filtered. The solvent is removed by evaporation in vacuo to afford a dark brown oil. This is purified by flash chromatography (hexane/ethyl acetate=1:1, followed by 100% ethyl acetate) to afford the title compound.

1. temperatureis heated
2. temperatureunder reflux for 2 h
3. washThe resulting aqueous suspension is washed with ethyl acetate (2×100 ml)
4. washThe combined organic layers are washed with water (3×100 ml) and brine (100 ml)
5. dry with materialdried (magnesium sulfate)
6. filtrationfiltered
7. customThe solvent is removed by evaporation in vacuo
8. customto afford a dark brown oil
9. customThis is purified by flash chromatography (hexane/ethyl acetate=1:1, followed by 100% ethyl acetate)