反应详情

Dimethyl 2,6-pyridinedicarboxylate (11.7 g, 59.9 mmol) was dissolved in methanol (300 mL). The solution was cooled in an ice bath while stirring under argon some starting material came back out of solution. Potassium hydroxide (3.52 g, 62.7 mmol) pellets were added and the mixture and it was stirred in an ice bath for 2 h. The mixture was then allowed to gradually warm to room temperature and stirred for 20 h. The solvent was removed under reduced pressure, and the pinkish residue was suspended in ethyl acetate (250 mL). The mixture stirred for 15 minutes and then the potassium salt was collected by filtration and washed with 2×25 mL of ethyl acetate. The solid was dissolved in water (200 mL). The solution was acidified to pH-3 with concentrated hydrochloric acid and extracted with chloroform (4×80 mL). The combined organic layers were dried over anhydrous Na2SO4, filtered, evaporated, and dried under vacuum to give the 6-[(methyloxy)carbonyl]-2-pyridinecarboxylic acid (6.71 g, 36.2 mmol, 60.4% yield) as a white solid. LC-MS m/z 182 (M+H)+, 0.75 min (ret time).

1. temperatureThe solution was cooled in an ice bath
2. stirringthe mixture and it was stirred in an ice bath for 2 h
3. stirringstirred for 20 h
4. customThe solvent was removed under reduced pressure
5. stirringThe mixture stirred for 15 minutes
6. filtrationthe potassium salt was collected by filtration
7. washwashed with 2×25 mL of ethyl acetate
8. dissolutionThe solid was dissolved in water (200 mL)
9. extractionextracted with chloroform (4×80 mL)
10. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
11. filtrationfiltered
12. customevaporated
13. customdried under vacuum