反应详情

To a stirred solution of 5-Bromosalicyclic acid (30 g, 135.5 mmol) in n-butylalcohol (60 mL) was added H2SO4 (95.6%, 289 μL, 5.42 mmol) in a 100 ml round bottom flask connected by a Dean-Stark trap/reflux condenser that was filled with 12 ml of n-butylalcohol. After heated to reflux for 2 days, the reaction was cooled down to R.T. and concentrated to give a pale yellow oil. The mixture was added 50 mL MeOH, followed by NH3 in MeOH (7 N, 116 mL). The reaction was stirred at R.T. for another 2 days, monitored by HPLC. After the reaction complete, it was concentrated to give a white solid. The crude solid was washed with small amount of EtOAc and hexane to afford 24 g of the product as a white crystalline solid (82% yield). 1H NMR (CDCl3) δ 12.15 (s, 1H), 7.54 (m, 2H), 6.97 (d, J=12 Hz, 1H), 6.00 (broad, 2H).

1. temperaturetrap/reflux condenser that
2. temperatureAfter heated
3. temperatureto reflux for 2 days
4. concentrationconcentrated
5. customto give a pale yellow oil
6. customAfter the reaction complete
7. concentrationit was concentrated
8. customto give a white solid
9. washThe crude solid was washed with small amount of EtOAc and hexane