反应详情

500 mg (2.473 mmol) of 5-hydroxypsoralen and 405.85 mg (3.957 mmol) of 5-chloro-1-pentyne were refluxed in 30 ml of acetonitrile in the presence of an excess of anhydrous potassium carbonate (2.0 gm) and catalytic amounts of potassium iodide for 24 hours. The progress of the reaction was monitored by thin layer chromatography. After 24 hours the reaction mixture was concentrated under reduced pressure. The oily residue was cooled, diluted with water and acidified with concentrated hydrochloric acid to pH 1. The aqueous phase was extracted with dichloromethane. The dichloromethane phase was extracted with 25 ml of 1% sodium hydroxide to separate the un-reacted 5-hydroxypsoralen. The dichloromethane phase was washed with acidic water and then with water to pH˜6-7. The organic phase was then dried over anhydrous sodium sulphate and concentrated to dryness. The residue was dissolved in methanol, decolorized with charcoal and re-crystallized from methanol.

1. concentrationAfter 24 hours the reaction mixture was concentrated under reduced pressure
2. temperatureThe oily residue was cooled
3. additiondiluted with water
4. extractionThe aqueous phase was extracted with dichloromethane
5. extractionThe dichloromethane phase was extracted with 25 ml of 1% sodium hydroxide
6. customto separate the un-reacted 5-hydroxypsoralen
7. washThe dichloromethane phase was washed with acidic water
8. dry with materialThe organic phase was then dried over anhydrous sodium sulphate
9. concentrationconcentrated to dryness
10. dissolutionThe residue was dissolved in methanol
11. customre-crystallized from methanol