反应详情

5-Acetyl-3-chloro-2-methylthiopyridine (24.1 g, 0.12 mol) was slurried in absolute ethanol (200 mL) and sodium borohydride (4.5 g, 0.118 mol) added in portions. The reaction mixture was stirred at room temperature for 48 hours and acidified to pH 2 with 2N hydrochloric acid. This was then diluted with water (200 mL) and the bulk of the ethanol evaporated under reduced pressure, the temperature of the mixture being maintained below 50° C. The reaction mixture was diluted with water (200 mL) and extracted twice with dichloromethane (15 mL). The combined organic extracts were washed with water (200 mL) and saturated sodium chloride solution (100 mL), dried over anhydrous sodium sulphate, and evaporated to dryness to give the desired product (21.9 g, 90%) as an orange oil.

1. customthe bulk of the ethanol evaporated under reduced pressure
2. temperaturethe temperature of the mixture being maintained below 50° C
3. additionThe reaction mixture was diluted with water (200 mL)
4. extractionextracted twice with dichloromethane (15 mL)
5. washThe combined organic extracts were washed with water (200 mL) and saturated sodium chloride solution (100 mL)
6. dry with materialdried over anhydrous sodium sulphate
7. customevaporated to dryness