反应详情

5.1 G of 2-(5H-[1]benzopyrano[2,3-b]pyridin-7-yl)propionic acid and 1.96 g of 2-dimethylaminoethanol are dissolved in 30 ml of pyridine. 4.2 g of p-tolylsulfonyl chloride is added in small portions to the pyridine solution with stirring at room temperature, and the mixture is stirred at 80°-90°C for 2 hours. The pyridine is distilled off under reduced pressure, and the residue is dissolved in chloroform. After addition of ice water, the solution is adjusted to pH 9 by addition of 15% sodium hydroxide. The mixture is thoroughly shaken, and the chloroform layer is separated. The chloroform layer is washed with water, dried over anhydrous magnesium sulfate, and concentrated. The residual oil is dissolved in 30 ml of isopropyl alcohol, and the solution is adjusted to pH 1-2 by addition of 20% alcoholic hydrochloric acid. After cooling, the crystalline precipitate is filtered off, and high vacuum dried to give 4.2 g of 2-dimethylaminoethyl 2-(5H-[1]benzopyrano[2,3-b]pyridin-7-yl)propionate hydrochloride melting at 167°-169°C.

1. stirringthe mixture is stirred at 80°-90°C for 2 hours
2. distillationThe pyridine is distilled off under reduced pressure
3. dissolutionthe residue is dissolved in chloroform
4. additionAfter addition of ice water
5. additionthe solution is adjusted to pH 9 by addition of 15% sodium hydroxide
6. stirringThe mixture is thoroughly shaken
7. customthe chloroform layer is separated
8. washThe chloroform layer is washed with water
9. dry with materialdried over anhydrous magnesium sulfate
10. concentrationconcentrated
11. dissolutionThe residual oil is dissolved in 30 ml of isopropyl alcohol
12. additionthe solution is adjusted to pH 1-2 by addition of 20% alcoholic hydrochloric acid
13. temperatureAfter cooling
14. filtrationthe crystalline precipitate is filtered off
15. customhigh vacuum dried