反应详情

A solution of 4-bromo-2-hydroxybenzoic acid (1.0 g) in methanol (10 ml) was treated cautiously with conc. sulphuric acid (0.5 ml) then stirred at 75° under nitrogen for 7 h. The mixture was concentrated under vacuum and the residue was partitioned between ethyl acetate (30 ml) and water (30 ml). The aqueous layer was re-extracted with ethyl acetate (30 ml) and the combined organic extracts were washed with saturated aqueous sodium bicarbonate (2×50 ml) and water (50 ml). The dried (MgSO4) extracts were concentrated under vacuum to give the title compound as a beige solid (0.7 g).

1. concentrationThe mixture was concentrated under vacuum
2. customthe residue was partitioned between ethyl acetate (30 ml) and water (30 ml)
3. extractionThe aqueous layer was re-extracted with ethyl acetate (30 ml)
4. washthe combined organic extracts were washed with saturated aqueous sodium bicarbonate (2×50 ml) and water (50 ml)
5. dry with materialThe dried (MgSO4) extracts
6. concentrationwere concentrated under vacuum