反应详情

6-Chloro-5-fluoro-pyridin-3-ol (300 mg, 2.03 mmol) is dissolved in DMF (10 mL). Potassium carbonate (562 mg, 4.07 mmol) is added followed by 2,2,3,3-tetrafluoropropyl trifluoromethanesulfonate (591 mg, 2.24 mmol) (For preparation of this reagent, see US2013/143900, Ex 1). The reaction is stirred at room temperature for 18 hours then allowed to stand at room temperature for 4 days. The reaction is diluted with aqueous NaHCO3 and ethyl acetate. The layers are separated and the aqueous layer is extracted with ethyl acetate (2×). The combined organic layers are washed with brine and concentrated. The crude material is purified via silica gel chromatography using a 0-10% ethyl acetate/hexanes gradient to give the title compound (440 mg, 83%). ES/MS (m/e): 262.0 (M+1).

1. customFor preparation of this reagent
2. waitto stand at room temperature for 4 days
3. customThe layers are separated
4. extractionthe aqueous layer is extracted with ethyl acetate (2×)
5. washThe combined organic layers are washed with brine
6. concentrationconcentrated
7. customThe crude material is purified via silica gel chromatography