反应详情

A solution of 5-chlorosalicylic acid (5.0 g) in ethanol (50 mL) was added with concentrated sulfuric acid (2.0 mL), and heated under reflux for 24 hours. After the ethanol was evaporated under reduced pressure, the resultant oil was dissolved in ethyl acetate, and the solution was washed with saturated aqueous solution of sodium hydrogencarbonate. The ethyl acetate layer was washed successively with water and saturated brine, and dried over anhydrous magnesium sulfate. Then, the solvent was evaporated under reduced pressure to obtain roughly purified 5-chlorosalicylic acid ethyl ester (5.3 g). This product was treated with 70% nitric acid (7.2 mL, d=1.42) in acetic anhydride (40 mL) under ice cooling. The reaction mixture was stirred at the same temperature for 6 hours, and poured into iced water, and the deposited crystals were collected by filtration. The crystals were washed with water, and dried under reduced pressure to obtain the title compound (1.48 g).

1. temperatureheated
2. temperatureunder reflux for 24 hours
3. customAfter the ethanol was evaporated under reduced pressure
4. dissolutionthe resultant oil was dissolved in ethyl acetate
5. washthe solution was washed with saturated aqueous solution of sodium hydrogencarbonate
6. washThe ethyl acetate layer was washed successively with water and saturated brine
7. dry with materialdried over anhydrous magnesium sulfate
8. customThen, the solvent was evaporated under reduced pressure