反应详情

温度

100 °C

A mixture of 3.0 g of methyl 5-chloro-3-formyl-2-hydroxybenzoate, 3.44 g of methyl α-bromophenylacetate, 8.28 g of potassium carbonate and 50 ml of dimethylformamide is heated at 70°-80° C. for 15 minutes and further heated at 100° C. for 10 minutes. After cooling, water is added to the mixture, and the aqueous mixture is acidified with 10% hydrochloric acid and then extracted with ethyl acetate. The extract is washed with an aqueous saturated sodium chloride solution, dried and evaporated to remove solvent. The residue is dissolved in 50 ml of ethanol, and 4.5 g of potassium hydroxide are added to the solution. The mixture is refluxed for 1 hour and then evaporated to remove solvent. Water is added to the residue, and the aqueous mixture is acidified with 10% hydrochloric acid and extracted with ethyl acetate. The extract is dried and evaporated to remove solvent. 150 ml of xylene and 30 mg of p-toluenesulfonic acid are added to the residue and the mixture is refluxed for 1 hour. The reaction mixture is evaporated to remove solvent and the residue is dissolved in ethyl acetate. The solution is washed, dried and evaporated to remove solvent. The residue is crystallized from isopropyl ether to give 2.32 g of 5-chloro-2-phenylbenzofuran-7-carboxylic acid.

1. temperatureis heated at 70°-80° C. for 15 minutes
2. temperatureAfter cooling
3. extractionextracted with ethyl acetate
4. washThe extract is washed with an aqueous saturated sodium chloride solution
5. customdried
6. customevaporated
7. customto remove solvent
8. dissolutionThe residue is dissolved in 50 ml of ethanol
9. addition4.5 g of potassium hydroxide are added to the solution
10. temperatureThe mixture is refluxed for 1 hour
11. customevaporated
12. customto remove solvent
13. additionWater is added to the residue
14. extractionextracted with ethyl acetate
15. customThe extract is dried
16. customevaporated
17. customto remove solvent
18. addition150 ml of xylene and 30 mg of p-toluenesulfonic acid are added to the residue
19. temperaturethe mixture is refluxed for 1 hour
20. customThe reaction mixture is evaporated
21. customto remove solvent
22. dissolutionthe residue is dissolved in ethyl acetate
23. washThe solution is washed
24. customdried
25. customevaporated
26. customto remove solvent
27. customThe residue is crystallized from isopropyl ether