反应详情

温度

70 °C

A solution of 50 g (0.32 mole) of 2,5-dihydroxybenzoic acid in 260 ml of methanol, at 0° C., was combined with 33 ml of sulphuric acid. The resulting solution was heated to 70° C. under stirring. After 6 hours the reaction mixture was cooled to room temperature and concentrated to small volume under vacuum. The resulting oily layer was taken up with sodium hydroxyde 5N and extracted with ethyl acetate the organic layer was washed with water, dried over sodium sulphate and evaporated under vacuum, to provide 52 g of methyl 2,5-dihydroxybenzoate which were used in the next step as obtained.

1. customat 0° C.
2. temperatureAfter 6 hours the reaction mixture was cooled to room temperature
3. concentrationconcentrated to small volume under vacuum
4. extractionextracted with ethyl acetate the organic layer
5. washwas washed with water
6. dry with materialdried over sodium sulphate
7. customevaporated under vacuum