反应详情

To a stirred solution of methyl 2,5-dimethyl-4-nitrobenzoate (523 mg, 2.5 mmol) in a 9:1 mixture of methanol and water (25 mL total) at 0° C. was added ammonium chloride (401 mg, 7.5 mmol). Zinc (1.63 g, 25 mmol) was added portionwise and the resulting mixture was stirred at room temperature overnight. The reaction mixture was then filtered through Celite and the Celite pad was washed with methanol. The filtrate was concentrated under reduced pressure and the resulting residue was dissolved in ethyl acetate. This solution was washed with saturated aqueous sodium bicarbonate, dried over anhydrous sodium sulfate and concentrated under reduced pressure to provide methyl 4-amino-2,5-dimethylbenzoate (450 mg) as a yellow oil. 1H NMR (300 MHz, CDCl3) δ 2.14 (s, 3H), 2.53 (s, 3H), 3.83 (s, 3H), 3.85 (br s, 2H), 6.48 (s, 1H), 7.72 (s, 1H).

1. filtrationThe reaction mixture was then filtered through Celite
2. washthe Celite pad was washed with methanol
3. concentrationThe filtrate was concentrated under reduced pressure
4. dissolutionthe resulting residue was dissolved in ethyl acetate
5. washThis solution was washed with saturated aqueous sodium bicarbonate
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationconcentrated under reduced pressure