反应详情

In an argon atmosphere, a hexane solution of n-butyllithium M, 8.22 ml, 13.2 mmol) was added to a solution of 2,5-dibromo-4-methylpyridine (3.00 g, 12.0 mmol) in diethyl ether (120 ml) at −78° C. After stirring the reaction mixture for 30 minutes, 2,5-difluorobenzaldehyde (1.34 ml, 12.0 mmol) was added. After stirring for 1 hour at the same temperature, saturated aqueous ammonium chloride was added at room temperature. After the organic layer was separated, the organic layer was dried over anhydrous sodium sulfate and filtered, and then the filtrate was concentrated under reduced pressure. The resulting residue was subjected to flash silica gel chromatography. The fraction obtained from an elution with hexane:ethyl acetate=4:1 was concentrated under reduced pressure, to obtain the title compound (1.26 g, 4.01 mmol, 34%) as a white solid.

1. additionwas added at room temperature
2. customAfter the organic layer was separated
3. dry with materialthe organic layer was dried over anhydrous sodium sulfate
4. filtrationfiltered
5. concentrationthe filtrate was concentrated under reduced pressure
6. customThe fraction obtained from an elution with hexane
7. concentrationethyl acetate=4:1 was concentrated under reduced pressure