反应详情

Ethyl (9-oxoxanthen-2-oxyacetate (10 g, 33 mmol) prepared as described above, was dissolved in 95% ethanol (150 mL), and 4 N aqueous KOH (30 mL, 0.12 mol) and water (15 mL) were added. The mixture was stirred for 35 minutes at 35°-40° C., cooled, and the solid precipitate which formed was collected by filtration, washed with absolute ether (3'20 mL), and air-dried. The structure of the potassium salt is shown below. Yield: 9.25 g (96%). TLC, Rf 0.90 [MeOH-H2O(4:1)]. NMR data in accordance with structure.

1. temperaturecooled
2. customthe solid precipitate which formed
3. filtrationwas collected by filtration
4. washwashed with absolute ether (3'20 mL), and
5. customair-dried