反应详情

Ethyl difluoro(2-pyridyl)acetate (1.00 g, 4.97 mmol, from Procedure 35, Step B) was dissolved in CH3OH (15 mL) in a 3-neck round bottom flask fitted with a mechanical stirrer, and the resulting solution was cooled in a dry ice/isopropanol bath. Sodium borohydride (114 mg, 3.0 mmol) was added in 2 portions 15 min. apart. After an additional 55 min., the cold reaction was quenched by the addition of saturated aq. ammonium chloride (6.5 mL) over 12 min. After 10 min., the cooling bath was removed and the mixture was stirred for 35 min. before being diluted with saturated aq. brine (100 mL) and extracted with ethyl acetate (4×75 mL). The combined organic layers were dried (sodium sulfate), decanted, and evaporated to give 1.02 g of crude 2,2-difluoro-2-(2-pyridyl)-1-methoxyethanol as an amber oil.

1. customfitted with a mechanical stirrer
2. temperaturethe resulting solution was cooled in a dry ice/isopropanol bath
3. customthe cold reaction
4. customwas quenched by the addition of saturated aq. ammonium chloride (6.5 mL) over 12 min
5. waitAfter 10 min.
6. customthe cooling bath was removed
7. additionbefore being diluted with saturated aq. brine (100 mL)
8. extractionextracted with ethyl acetate (4×75 mL)
9. dry with materialThe combined organic layers were dried (sodium sulfate)
10. customdecanted
11. customevaporated