反应详情

A solution of the product from step (vi) (19.0 g) and lithium hydroxide (5.6 g) in tetrahydrofuran (200 ml) and water (100 ml) was heated at reflux for 4 hours and concentrated under reduced pressure. The residue was suspended in water, acidified with 2N HCl and extracted with ethyl acetate. The combined extracts were washed with water and saturated brine. The organic phase was collected, dried (MgSO4) and solvent evaporated to give a brown solid. Purification was by flash chromatography, eluting with 50% ethyl acetate in dichloromethane with 0.5% acetic acid.

1. temperatureat reflux for 4 hours
2. concentrationconcentrated under reduced pressure
3. extractionextracted with ethyl acetate
4. washThe combined extracts were washed with water and saturated brine
5. customThe organic phase was collected
6. dry with materialdried (MgSO4) and solvent
7. customevaporated
8. customto give a brown solid
9. customPurification
10. washeluting with 50% ethyl acetate in dichloromethane with 0.5% acetic acid