反应详情

To a solution of tert-butyl 4-[3-(3-acetoxy-4-acetyl-2-propylphenoxy)propoxy]-3-bromobenzoate (1.5 g) in dioxane (10 ml) was added a cooled solution of 2 N hydrogen chloride in dioxane (10 ml) at 20° C. under stirring. The reaction mixture was warmed to room temperature, and stirred for 30 minutes. To the mixture was added an additional cooled solution of 2 N hydrogen chloride in dioxane (10 ml). The mixture was stirred for 1.5 hours and subjected to concentration under reduced pressure. The residue was dissolved in chloroform (30 ml), and the solution was washed with water (30 ml) and dried with magnesium sulfate. The solvent was removed by evaporation, and the residue was dissolved in isopropyl ether. The solution was treated with activated carbon, and to the solution was added hexane to give crystals. The crystals were collected by filtration, subjected to silica gel column chromatography, and subjected to recrystallization from aqueous ethanol to give colorless crystals of 4-[3-(3-acetoxy-4-acetyl-2-propylphenoxy)propoxy]-3-bromobenzoic acid (0.35 g). M.p. 154°-156° C.

1. stirringstirred for 30 minutes
2. stirringThe mixture was stirred for 1.5 hours
3. concentrationsubjected to concentration under reduced pressure
4. dissolutionThe residue was dissolved in chloroform (30 ml)
5. washthe solution was washed with water (30 ml)
6. dry with materialdried with magnesium sulfate
7. customThe solvent was removed by evaporation
8. dissolutionthe residue was dissolved in isopropyl ether
9. additionThe solution was treated with activated carbon
10. additionto the solution was added hexane
11. customto give crystals
12. filtrationThe crystals were collected by filtration
13. customsubjected to recrystallization from aqueous ethanol