反应详情

p-Toluene sulfonic acid hydrate (0.282 g, 1.48 mmol) was dissolved in toluene (11 mL) and heated to reflux overnight with azeotropic removal of H2O (Dean-Stark trap). The next day, the reaction was cooled to room temperature and the product of Example 28, dissolved in toluene (4 mL), was added. The reaction was heated back to reflux for 0.5 hours. The reaction was cooled to room temperature and poured into NaHCO3 (sat) and extracted 3 times with ether. The organics were combined, washed with brine, dried over MgSO4, concentrated in vacuo. The residue was purified by column chromatography using hexane/ethyl acetate as eluant (gradient 100% to 9/1) to provide 0.278 g (97%) of methyl 3-amino-2,6-dimethoxyisonicotinate as a yellow solid. Electrospray Mass Spec: 212.8 (M+H)+

1. temperatureheated
2. additionwas added
3. temperatureThe reaction was heated back
4. temperatureto reflux for 0.5 hours
5. temperatureThe reaction was cooled to room temperature
6. extractionextracted 3 times with ether
7. washwashed with brine
8. dry with materialdried over MgSO4
9. concentrationconcentrated in vacuo
10. customThe residue was purified by column chromatography