反应详情

温度

0 °C

To 3,5-dihydroxybenzoic acid (20 g, 129 mmol) was added NaOH (15.6 g, 390 mmol) in 100 mL water. After the mixture was cooled to 0° C., Ac2O (13.2 g, 129 mmol) was added. The solution was stirred for 40 min and then acidified with 10% H2SO4 at 0° C. The precipitate was filtered and washed with cold water. The crude product was recrystallized from water to give 3-acetoxy-5-hydroxybenzoic acid (15.2 g, 60%). Data are: 1H NMR (Aceton-d6, 300 MHz) δ 8.96 (s, 1H), 7.40 (dd, 1H, J=1.5 Hz), 7.26 (dd, 1H, J=1.5 Hz), 6.86 (t, 1H, 2.1H), 2.27 (s, 3H); HRMS (EI+) found 196.0380 M+, calcd 196.0372 for C9H8O6.

1. filtrationThe precipitate was filtered
2. washwashed with cold water
3. customThe crude product was recrystallized from water