反应详情

Phosphorus oxychloride (3.36 ml) is added dropwise over a period of 20 minutes to dimethylformamide (10.6 g) maintained at 0°-3°. After complete addition a solution of 2-(3-pyridyl)indole (6.50 g) in dimethylformamide (20 ml) is added dropwise over a period of 30 minutes at such a rate so that the reaction temperature does not exceed 10°. The cooling bath is then removed and the viscous solution heated to and maintained at 35°-40° for 1 hour. The reaction mixture is treated with crushed ice (50 g). A solution of sodium hydroxide (24.4 g) in 65 ml of water is added slowly. After the addition the resulting red-orange solution is heated rapidly to reflux and maintained at reflux for about 2 minutes. The solution is allowed to cool to room temperature, then placed in a freezer for 2 days. The resulting precipitate is collected and washed well with water to give an orange solid which is recrystallized from methanol (240 ml) to give 2-(3pyridyl)-indole-3-carboxaldehyde, m.p. 236°-238°.

1. temperaturemaintained at 0°-3°
2. additionis added dropwise over a period of 30 minutes at such a rate so that the reaction temperature
3. customdoes not exceed 10°
4. customThe cooling bath is then removed
5. temperaturethe viscous solution heated to and
6. temperaturemaintained at 35°-40° for 1 hour
7. additionThe reaction mixture is treated with crushed ice (50 g)
8. additionA solution of sodium hydroxide (24.4 g) in 65 ml of water is added slowly
9. additionAfter the addition the resulting red-orange solution
10. temperatureis heated rapidly
11. temperatureto reflux
12. temperaturemaintained
13. temperatureat reflux for about 2 minutes
14. customThe resulting precipitate is collected
15. washwashed well with water
16. customto give an orange solid which
17. customis recrystallized from methanol (240 ml)