反应详情

23.7 g of double-distilled thionyl chloride are added dropwise to a solution, stirred and heated to 70° C., of 30.2 g of 2-(5-chloro-2,3-dihydro-2-oxo-3-phenyl-3-benzofuranyl)acetic acid in 250 ml of anhydrous benzene. When the addition is complete, the mixture is heated to reflux until the evolution of gas has completely ceased. The medium is concentrated under vacuum, the residue washed with 200 ml of anhydrous benzene and the solvent evaporated off. This operation is repeated twice and the product is left to crystallize at room temperature. The crystals are washed with petroleum ether and filtered off, and 31 g of pure product are obtained.

1. additionWhen the addition
2. temperaturethe mixture is heated
3. temperatureto reflux until the evolution of gas
4. concentrationThe medium is concentrated under vacuum
5. washthe residue washed with 200 ml of anhydrous benzene
6. customthe solvent evaporated off
7. waitthe product is left
8. customto crystallize at room temperature
9. washThe crystals are washed with petroleum ether
10. filtrationfiltered off