反应详情

温度

0 °C

Under a stream of nitrogen, 5.0 g (29.07 mmol) of 4-bromo-2-picoline and 10.2 g (60.95 mmol) of ethyl 4-fluorobenzoate are placed in a round-bottomed flask and dissolved in 50 mL of anhydrous tetrahydrofuran. The mixture is cooled to 0° C. and 70 mL (70 mmol) of a lithium hexamethyldisilazane solution (1M in tetrahydrofuran) are added dropwise. After addition, the mixture is stirred at room temperature for 2 hours, cooled to 5° C., and 100 mL of water are then gradually added. The medium is then diluted with 250 mL of ethyl acetate and 100 mL of water. The organic phase is separated out and the aqueous phase is extracted twice with 100 mL of ethyl acetate. The organic phases are then combined, dried over sodium sulfate and filtered. 15 g of silica are then added to the filtrate, and the resulting mixture is stirred and then concentrated under reduced pressure. The powder obtained is used as a solid deposit for a chromatography on silica gel, eluting with a mixture of cyclohexane and ethyl acetate (9/1). 7.5 g (88%) of compound are obtained in the form of a yellow powder.

1. additionAfter addition
2. temperaturecooled to 5° C.
3. customThe organic phase is separated out
4. extractionthe aqueous phase is extracted twice with 100 mL of ethyl acetate
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. addition15 g of silica are then added to the filtrate
8. stirringthe resulting mixture is stirred
9. concentrationconcentrated under reduced pressure
10. customThe powder obtained
11. washeluting with a mixture of cyclohexane and ethyl acetate (9/1)