Реакция #1769

Уравнение реакции

methyl 4-hydroxy-2-methoxybenzoate

3,5-dichloro-1-fluoropyridinium triflate

→

methyl 5-fluoro-4-hydroxy-2-methoxybenzoate

Растворители

CH2Cl2

Условия реакции

Обработка

1. 1
   ТемператураThe solution was refluxed for 48 h
2. 2
   ДругоеThe crude oil was purified by pressurized silica gel column chromatography
3. 3
   ДругоеEvaporation of the CH2Cl2

Методика

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.

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