反应详情

With ice-cooling, 400 ml of 1.25N hydrochloric acid in methanol are added to 43.8 g (60.3 mmol) of the compound from Example 17A. After 1 h, the mixture is diluted with dichloromethane, and the aqueous phase is then separated off. The organic phase is washed twice with water, dried over sodium sulphate and, after filtration, concentrated to dryness under reduced pressure. The residue is applied to silica gel and chromatographed using a gradient of cyclohexane and ethyl acetate. The product-containing fractions are combined and concentrated to dryness under reduced pressure. This gives 19.6 g (66% of theory) of the desired product.

1. temperatureWith ice-cooling
2. customthe aqueous phase is then separated off
3. washThe organic phase is washed twice with water
4. dry with materialdried over sodium sulphate
5. filtrationafter filtration
6. concentrationconcentrated to dryness under reduced pressure
7. customchromatographed
8. concentrationconcentrated to dryness under reduced pressure