反应详情

To a chilled, stirred solution of 24.4 g of Compound XIX in 250 ml pyridine was added 89 g of triphenyl phosphine. Nitrogen bubbles evolved. The solution was stirred with ice cooling for 45 minutes and then allowed to warm to room temperature. After 45 minutes at room temperature 100 ml of concentrated ammonium hydroxide was added and the mixture stirred overnight. The mixture was partitioned between 500 ml of 0.5N citric acid and 250 ml of ether. The aqueous phase was washed with ether (2×250 ml) to remove triphenyl phosphine oxide. The aqueous phase was saturated with sodium chloride and extracted with 1-butanol (4×250 ml) and dichloromethane (4×250 ml). The combined alcohol and dichloromethane extracts were concentrated under reduced pressure and the residue was taken up in 100 ml of ethanol. Concentrated hydrochloric acid (15 ml) was added and the solvent removed under reduced pressure. The residue was crystallized from ethanol/ether. The hygroscopic crystals were dried under vacuum.

1. stirringthe mixture stirred overnight
2. customThe mixture was partitioned between 500 ml of 0.5N citric acid and 250 ml of ether
3. washThe aqueous phase was washed with ether (2×250 ml)
4. customto remove triphenyl phosphine oxide
5. extractionextracted with 1-butanol (4×250 ml) and dichloromethane (4×250 ml)
6. concentrationThe combined alcohol and dichloromethane extracts were concentrated under reduced pressure
7. additionConcentrated hydrochloric acid (15 ml) was added
8. customthe solvent removed under reduced pressure
9. customThe residue was crystallized from ethanol/ether
10. customThe hygroscopic crystals were dried under vacuum