[NH2:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[O:11][CH3:12].Cl.[CH3:14][CH2:15]O>>[CH2:14]([O:7][C:6](=[O:8])[C:5]1[CH:9]=[CH:10][C:2]([NH2:1])=[C:3]([O:11][CH3:12])[CH:4]=1)[CH3:15]To a solution of 3.343 g (20 mmole) of 4-amino-3-methoxybenzoic acid in 200 mL EtOH is bubbled a stream of HCl gas for three minutes. The HCl saturated solution is stirred at room temperature for two days. Solvent is evaporated under vacuum and the resulting residue is dissolved in 100 mL water. The water layer is basified with K2CO3 and extracted with CH2Cl2 (3×200 mL). The combined CH2Cl2 layer is washed with saturated NaHCO3 (200 mL), brine and then dried over MgSO4, filtered and evaporated under reduced pressure to give the desired product.
Wird geladen…