反应详情

To a solution of 5-benzyloxy-4-methoxy-2-(3,4,5-trimethoxybenzoyl)-benzoic acid (90 g) in dimethylformamide (900 MI) are added potassium carbonate (60.5 g) and di-tert-butyl bromomalonate (64.6 g), and the mixture is stirred at room temperature for three hours. To the reaction mixture are added ethyl acetate and water. The ethyl acetate layer is separated, washed, dried, and concentrated under reduced pressure. To the residue is added a 4M solution of hydrogen chloride in ethyl acetate (500 ml), and the mixture is stirred at room temperature for five hours. The precipitated crystals are collected by filtration, washed, dried, and dissolved in a mixture of acetic acid (40 ml) and dioxane (80 ml). The mixture is heated under reflux for five hours, and the precipitated crystals are collected by filtration. washed, and dried to give 7-benzyloxy-6-methoxy-4-(3,4,5-trimethoxyphenyl)isocoumarin-3-carboxylic acid (70.0 g) as listed in Table 59.

1. customThe ethyl acetate layer is separated
2. washwashed
3. customdried
4. concentrationconcentrated under reduced pressure
5. additionTo the residue is added a 4M solution of hydrogen chloride in ethyl acetate (500 ml)
6. stirringthe mixture is stirred at room temperature for five hours
7. filtrationThe precipitated crystals are collected by filtration
8. washwashed
9. customdried
10. dissolutiondissolved in a mixture of acetic acid (40 ml) and dioxane (80 ml)
11. temperatureThe mixture is heated
12. temperatureunder reflux for five hours
13. filtrationthe precipitated crystals are collected by filtration
14. washwashed
15. customdried