反应详情

110 g (300 mmol) esculine×1.5 H2O, 70 g (450 mmol) ethyl iodide and 82.8 g (600 mmol) of potassium carbonate are agitated in 400 ml DMF for 30 h at 85° C. This was followed by filtration, reduction of the filtrate to approximately 250 ml, the addition of approximately 200 ml ethanol and crystallization at 0° C. The crystals were boiled in 800 ml of 2N sulfuric acid for 5 h under reflux. The product was vacuum filtered, washed with water and recrystallized from water and ethanol: yield 43.2 g (70%), fusion point 145° to 146° C.

1. filtrationThis was followed by filtration, reduction of the filtrate to approximately 250 ml
2. additionthe addition of approximately 200 ml ethanol and crystallization at 0° C
3. temperatureunder reflux
4. filtrationfiltered
5. washwashed with water
6. customrecrystallized from water and ethanol
7. customyield 43.2 g (70%), fusion point 145° to 146° C.