反应详情

To a solution of 1.875 g (4.38 mmol) of the product of Step K in methanol (20 mL) was added 1N NaOH (4.82 mL, 4.82 mmol) at rt. The solution was stirred at rt for 3 hours. After the solvent was evaporated under reduced pressure, the residue was dissolved in H2O (30 mL) and washed with ethyl acetate (30 mL). The aqueous layer was acidified to pH=3 with 2N HCl. A milky emulsion was extracted with ethyl acetate (3×). The combined organic layer was washed with brine, and was dried over anhydrous MgSO4. Concentration afforded 0.929 g of the title compound as a colorless glass.

1. customAfter the solvent was evaporated under reduced pressure
2. dissolutionthe residue was dissolved in H2O (30 mL)
3. washwashed with ethyl acetate (30 mL)
4. extractionA milky emulsion was extracted with ethyl acetate (3×)
5. washThe combined organic layer was washed with brine
6. dry with materialwas dried over anhydrous MgSO4
7. concentrationConcentration