反应详情

A stirred mixture of methyl 3-methoxy-4-nitrobenzoate (1.20 g, 5.7 mmol) and 5% Pd—C (1.0 g) in EtOH (30 mL) and THF (20 mL) was hydrogenated overnight at 1 atm. The mixture was filtered and the filtrate was evaporated. The residue was chromatographed on silica-gel with CHCl3 as eluent, and the solid obtained was further purified by recrystallization from CHCl3-n-hexane to give 805 mg (78%) methyl 4-amino-3-methoxybenzoate as white plates. mp 126–128; IR (KBr) 3475, 1700 cm−1; 1H-NMR (CDCl3) δ 3.86 (3H, s), 3.89 (3H, s), 4.21 (2H, br s), 6.66 (1H, d, J=8.3 Hz), 7.45 (1H, d, J=1.9 Hz), 7.54 (1H, dd, J=1.9 and 8.3 Hz); MS (FAB) m/z 182 (M++1); Anal. Calcd for C9H11NO3: C, 59.66; H, 6.12; N, 7.73. Found: C, 59.65; H. 6.15; N, 7.65.

1. filtrationThe mixture was filtered
2. customthe filtrate was evaporated
3. customThe residue was chromatographed on silica-gel with CHCl3 as eluent
4. customthe solid obtained
5. customwas further purified by recrystallization from CHCl3-n-hexane