反应详情

To 3,6-dihydroxy-xanthone (0.58 g, 1 equivalent) is added 10 ml of ethanol, then 117 mg of KOH 0.8 equivalents), followed by 0.58 g of CF3(CH2)5Br (1 equivalent); after two hours of boiling this mixture, the pH had dropped to the acidic range, and another 100 mg of KOH was added and heating continued overnight. The cooled mixture was diluted with water (50 ml) and extracted with ethyl acetate (3×50 ml), the combined extracts washed with 5 ml of water and brought to dryness. Separation of the 3-component mixture was achieved by chromatography (100 g of silica gel, column diameter 5 cm) with solvents of increasing polarity: Solvents used: ethyl acetate (A), hexane (isomeric mixture) (B), ethanol (C)

1. additionthe pH had dropped to the acidic range
2. temperatureheating continued overnight
3. extractionextracted with ethyl acetate (3×50 ml)
4. washthe combined extracts washed with 5 ml of water
5. customSeparation of the 3-component mixture
6. temperatureof increasing polarity