反应详情

A solution of 6-Amino-5-nitro-nicotinic acid (2) (15.2 g, 82.5 mmol) in MeOH (250 ml) and H2SO4 (conc. 25 ml) was heated at reflux for 5 h. The solution was concentrated in vacuo and the residue treated with saturated aqueous NaHCO3 solution until slightly basic. The resulting solid was collected by filtration, rinsed with H2O and dried in vacuo to give the product as a yellow solid (4.8 g, 25 mmol, 30%) that was used as is without further purification. TLC of the solid in DCM/MeOH (19:1) showed a less polar compound at Rf=0.5 compared to the baseline starting material.

1. temperatureat reflux for 5 h
2. concentrationThe solution was concentrated in vacuo
3. additionthe residue treated with saturated aqueous NaHCO3 solution until slightly basic
4. filtrationThe resulting solid was collected by filtration
5. washrinsed with H2O
6. customdried in vacuo