反应详情

5.2 g of sodium hydroxide was dissolved in 30 ml of water, and the solution was cooled to a temperature of 0° C. or below. With stirring, to this were added dropwise 2.7 ml of bromine and then 40 ml of a dioxane solution containing 4.14 g of 3-acetyl-2-[2-(4-methoxyphenyl)ethyl]-5-benzofurancarbonitrile obtained in the above step d). The resulting mixture was stirred at 0° C. for 45 minutes with ice cooling for 1 hour. The resulting reaction solution was mixed with water, adjusted to pH 2 with concentrated hydrochloric acid, and then extracted with chloroform. The resulting organic layer was washed with water and dried to distill off the solvent. Thereafter, the resulting residue was purified by subjecting it to silica gel column chromatography using chloroform as an eluant, thereby obtaining 1.44 g of 5-cyano-2-[2-(4-methoxyphenyl)ethyl]-3-benzofurancarboxylic acid.

1. temperaturethe solution was cooled to a temperature of 0° C. or below
2. customobtained in the above step d)
3. stirringThe resulting mixture was stirred at 0° C. for 45 minutes with ice cooling for 1 hour
4. customThe resulting reaction solution
5. extractionextracted with chloroform
6. washThe resulting organic layer was washed with water
7. customdried
8. distillationto distill off the solvent
9. customThereafter, the resulting residue was purified