反应详情

A suspension of 6-chloro-5-[(4-chlorophenyl)azo]-2,4-pyrimidinediamine (24.55 g, 0.0906 mol) in ethanol (640 ml), water (640 ml) and acetic acid (64 ml) was heated to 70° under nitrogen. Zinc dust (75 g) was added slowly over 1 hour, and then the reaction was stirred an additional hour at 70°. Then the reaction was cooled to room temperature and filtered under nitrogen. The filtrate was cooled to 0° and the pH was raised to 10 with 10% sodium hydroxide (400 ml). The precipitated zinc hydroxide was removed by filtration through Celite, and the dark red filtrate was neutralized to pH 7 with glacial acetic acid and concentrated to 300 ml. Water (50 ml) was added, the reaction was cooled to 0°, and the pH raised to 9 with 10% NaOH. The solution was allowed to stand at 5° for 3 days. The crystals were collected, washed with water (50 ml) and then ether (50 ml), and dried at 35° for 16 hours in vacuo to give 10.94 g of desired product.

1. temperaturewas heated to 70° under nitrogen
2. filtrationfiltered under nitrogen
3. temperatureThe filtrate was cooled to 0°
4. temperaturethe pH was raised to 10 with 10% sodium hydroxide (400 ml)
5. customThe precipitated zinc hydroxide was removed by filtration through Celite
6. concentrationconcentrated to 300 ml
7. additionWater (50 ml) was added
8. temperaturethe reaction was cooled to 0°
9. temperaturethe pH raised to 9 with 10% NaOH
10. customThe crystals were collected
11. washwashed with water (50 ml)
12. dry with materialether (50 ml), and dried at 35° for 16 hours in vacuo