反应详情

To a stirred solution of the methyl 4-hydroxy-2-methoxybenzoate (1 g, 5 mmol, from Step 3) in CH2Cl2 (20 mL) was added 3,5-dichloro-1-fluoropyridinium triflate (2.25 g, 6 mmol). The solution was refluxed for 48 h and then cooled to ambient temperature and stripped down under reduced pressure. The crude oil was purified by pressurized silica gel column chromatography using 99:1 CH2Cl2 :MeOH. Evaporation of the CH2Cl2 :MeOH mixture gave the desired methyl 5-fluoro-4-hydroxy-2-methoxybenzoate as a white powder.

1. temperatureThe solution was refluxed for 48 h
2. customThe crude oil was purified by pressurized silica gel column chromatography
3. customEvaporation of the CH2Cl2