反应详情

A mixture of commercially available 6-oxo-1,6-dihydropyridine-2-carboxylic acid (4.000 g; 28.75 mmol) and concentrated H2SO4 (3.5 ml) in anh. MeOH (65 ml) was refluxed, under nitrogen, for 22 h. MeOH was removed under reduced pressure, and the residue was basified by addition of a solution of 10% aq. NaHCO3. The mixture was then extracted with DCM (3×), and the mixed organic layers were dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure affording methyl 6-oxo-1,6-dihydropyridine-2-carboxylate as a beige solid. LC-MS (conditions D): tR=0.54 min.; no ionisation.

1. temperaturewas refluxed, under nitrogen, for 22 h
2. customMeOH was removed under reduced pressure
3. additionthe residue was basified by addition of a solution of 10% aq. NaHCO3
4. extractionThe mixture was then extracted with DCM (3×)
5. dry with materialthe mixed organic layers were dried over anh. MgSO4
6. filtrationfiltered
7. concentrationconcentrated to dryness under reduced pressure