反应详情

温度

-70 °C

436 ml of a 2M solution of the sodium salt of hexamethyldisilazane in THF are cooled to −60° C., under a nitrogen atmosphere, 400 ml of THF are added, followed dropwise by a solution of 75 g of 4-bromophenylacetic acid in 100 ml of THF and the medium is left for 1 hour 30 minutes with stirring at −70° C. 67.9 g of methyl 2,4-dichlorobenzoate are then added dropwise, the medium is left for 30 minutes, with stirring, and then the temperature is allowed to rise to 5° C. The reaction mixture is poured over an ice/1 liter of 2N HCl mixture, extracted with ether, the organic phase is washed with a saturated NaHCO3 solution, with water, dried over Na2SO4 and the solvent is evaporated under vacuum to a volume of 200 ml, pentane is added and the crystallized product formed is drained. 80 g of the expected compound are obtained.

1. waitthe medium is left for 30 minutes
2. stirringwith stirring
3. customto rise to 5° C
4. extractionextracted with ether
5. washthe organic phase is washed with a saturated NaHCO3 solution, with water
6. dry with materialdried over Na2SO4
7. customthe solvent is evaporated under vacuum to a volume of 200 ml, pentane
8. additionis added
9. customthe crystallized product formed