反应详情

To a heterogeneous mixture of methyl 4-bromo-3-hydroxybenzoate (1.5 g, 6.49 mmol) and potassium carbonate (1.795 g, 12.98 mmol) in anhydrous acetone (50 mL) was added 3-bromo-2-methylprop-1-ene (2.62 mL, 26.0 mmol) at rt. The mixture was stirred rt for 4 h. The insoluble material was removed by filtration. The filtrate was concentrated under vacuum. The residue was diluted with ethyl acetate (100 mL), washed sequentially with 1 N NaOH solution (30 mL), water (2×40 mL), and brine (30 mL). The organic solution was dried over anhydrous MgSO4 and concentrated under vacuum. The residue was applied to ISCO (80 g silica gel, 5-10% ethyl acetate/hexane) to provide the desired product, methyl 4-bromo-3-(2-methylallyloxy)benzoate (1.81 g, 6.35 mmol, 98% yield), as a colorless oil.

1. customThe insoluble material was removed by filtration
2. concentrationThe filtrate was concentrated under vacuum
3. additionThe residue was diluted with ethyl acetate (100 mL)
4. washwashed sequentially with 1 N NaOH solution (30 mL), water (2×40 mL), and brine (30 mL)
5. dry with materialThe organic solution was dried over anhydrous MgSO4
6. concentrationconcentrated under vacuum