反应详情

Sodium hydroxide (32.6 mL, 65.19 mmol) was added to a stirred suspension of methyl 8-bromo-2-morpholino-4-oxo-4H-chromene-6-carboxylate (8 g, 21.73 mmol) dissolved in MeOH (42 mL) and THF (21 mL) at 0° C. The resulting suspension was stirred at room temperature for 1 h. MeOH (60 mL), THF (10 mL) and water (10 mL) were then added to help stirring. Upon completion, the reaction was cooled to 0° C. and HCl 2N was added to the suspension until pH 2. The solid was collected by filtration, washed with water, AcOEt, diethyl ether and dried with P205 under vacuum at 50° C. to give 8-bromo-2-morpholino-4-oxo-4H-chromene-6-carboxylic acid (7.0 g, 91%). Mass Spectrum: m/z [M+H]+=354.

1. customat 0° C
2. stirringto help stirring
3. temperatureUpon completion, the reaction was cooled to 0° C.
4. filtrationThe solid was collected by filtration
5. washwashed with water, AcOEt, diethyl ether
6. customdried with P205 under vacuum at 50° C.