反应详情

This nitropyridine (300 mg, 1.8 mmol) was dissolved in a mixed solvent of acetic acid (7 ml) and conc. hydrochloric acid (0.5 ml), and zinc (692 g, 10.6 mmol) was added thereto in small portions while being cooled with ice for 5 minutes. After the mixture was stirred for 30 minutes at the room temperature, the reaction mixture was filtered, and the filtrate was neutralized with an aqueous solution of sodium hydrogencarbonate, and extracted with methylene chloride. The organic layer was washed with water and then with a saturated aqueous solution of sodium chloride, and dried over sodium sulfate. Thereafter, the solvent was distilled off, and the resulting crude product was purified through silica gel chromatography (eluent-hexane:ethyl acetate=1:1→chloroform:methanol=20:1) to obtain 158 mg (yield 64%) of 2-amino-5-methylthiopyridine as a pale-yellow powdery crystal.

1. additionwas added
2. temperaturein small portions while being cooled with ice for 5 minutes
3. filtrationthe reaction mixture was filtered
4. extractionextracted with methylene chloride
5. washThe organic layer was washed with water
6. dry with materialwith a saturated aqueous solution of sodium chloride, and dried over sodium sulfate
7. distillationThereafter, the solvent was distilled off
8. customthe resulting crude product was purified through silica gel chromatography (eluent-hexane:ethyl acetate=1:1→chloroform:methanol=20:1)