反应详情

A solution of N-[3-[(4-fluorobenzoyl)amino]-2-pyridinyl]glycine ethyl ester (70.0 g, 0.2205 mole) in ethylene glycol was refluxed for 2 hours, cooled and 14% of the solution was removed. To the remaining solution (0.19 mole) was added 88 ml of water and solid potassium hydroxide pellets (21.4 g, 0.38 mole). The solution was heated at reflux for an additional 11/4 hours, filtered into ice water (2 liter) and acidified with 3N hydrochloric acid. The resulting solid was collected by filtration, washed with water and dried under high vacuum at 60° C. overnight to give 45.5 g of crude title compound (88% yield). A 3.5-g porton of the solid was dissolved in hot methanol and filtered while hot, and water was added to the cloud point. Upon cooling to room temperature, solid precipitated which was collected and recrystallized again from methanol/water to give 2.00 g of title compound after drying under high vacuum at 50° C., mp >250° C.

1. temperaturecooled
2. custom14% of the solution was removed
3. temperatureThe solution was heated
4. temperatureat reflux for an additional 11/4 hours
5. filtrationfiltered into ice water (2 liter)
6. filtrationThe resulting solid was collected by filtration
7. washwashed with water
8. customdried under high vacuum at 60° C. overnight
9. customto give 45.5 g of crude title compound (88% yield)
10. filtrationfiltered while hot, and water
11. additionwas added to the cloud point
12. customsolid precipitated which
13. customwas collected
14. customrecrystallized again from methanol/water