反应详情

To a solution of the compound (3.16 g) obtained in (2) above in ethanol (5 ml) was added a 2.7N hydrochloric acid-ethanol solution (10 ml) and the mixture was stirred with refluxing for 2 hours. Ethanol was distilled away under reduced pressure, and the mixture was neutralized with a saturated aqueous sodium hydrogencarbonate solution and extracted with ethyl acetate. The extract was dried over magnesium sulfate and the solvent was distilled away under reduced pressure to give 4.10 g of a pale-brown solid (yield 97%).

1. temperaturewith refluxing for 2 hours
2. distillationEthanol was distilled away under reduced pressure
3. extractionextracted with ethyl acetate
4. dry with materialThe extract was dried over magnesium sulfate
5. distillationthe solvent was distilled away under reduced pressure