反应详情

A solution of 3-amino-4-hydroxybenzoic acid (0.142 g, 0.927 mmol) and the acyl chloride prepared from acid 74 (in 84% yield) (0.259 g, 1.019 mmol) in DCM (5 ml) and pyridine (6 ml) was stirred at room temperature for under at for 24 h. The solvent was removed under reduced pressure. HCl (aq, 4 M, 6 ml) was added and the precipitate was filtered, washed with water (10 ml) and dried under vacuum. Trituration with methanol (15 ml) and acetone (10 ml) afforded 75 as an off-white solid (0.084 g, 0.230 mml, 25%). 1H NMR (400 MHz, DMSO-d6) δ 3.92 (3H, s), 7.00 (1H, d, J 8.4 Hz), 7.67 (1H, d, J 8.8 Hz), 8.04-8.10 (2H, m), 8.16-8.27 (2H, m), 8.33 (1H, s), 8.70-8.66 (2H, m), 9.80 (1H, s), 10.55 (1H, bs). 13C NMR (100 MHz, DMSO-d6) δ 53.09, 116.18, 122.59, 125.94, 126.45, 126.26, 126.80, 128.45, 128.48, 129.19, 130.35, 130.40, 130.93, 134.13, 134.66, 134.94, 154.61, 165.85, 166.84, 167.73. νmax (solid)/(cm−1) 3059, 1716, 1666, 1592, 1541, 1283, 1247, 1132, 759.

1. customThe solvent was removed under reduced pressure
2. additionHCl (aq, 4 M, 6 ml) was added
3. filtrationthe precipitate was filtered
4. washwashed with water (10 ml)
5. customdried under vacuum