反应详情

To toluene (25 mL) suspension of 0.16 g of dichlorobis(triphenylphosphine)palladium(II) were added 0.12 g of triphenylphosphine, 0.01 g of sodium borohydride, 5.79 g of potassium tert-butoxide and 2.92 g of ethyl cyanoacetate, which was then stirred at room temperature for 10 minutes. Thereto were added 5.00 g of 5-bromobenzothiophene and 25 mL of toluene, which was then refluxed for 4 hours. Thereto was added 0.14 g of tetrakis(triphenylphosphine)palladium(0), which was then refluxed for 2 hours. Next, to the reaction solution were added 25 mL of ethanol, 2.82 g of sodium hydroxide and 5 mL of water, which was then refluxed for 6 hours. Thereto was added 2.82 g of sodium hydroxide, which was then refluxed for 5 hours. To the reaction mixture were added 15 mL of water and 0.5 g of activated carbon, and insoluble matter was filtered off. The aqueous layer was separated, and to the solution was added 35 mL of ethanol. The pH was adjusted to 2 with 15 mL of hydrochloric acid. Thereto was added 15 mL of water, which was then stirred at 40° C. Thereto was added 30 mL of water, which was stirred. After that, it was cooled. The precipitate was collected by filtration to provide 3.38 g of 2-(1-benzothiophen-5-yl)acetic acid as pale yellow solid form.

1. temperaturewas then refluxed for 4 hours
2. temperaturewas then refluxed for 2 hours
3. temperaturewas then refluxed for 6 hours
4. temperaturewas then refluxed for 5 hours
5. filtrationwas filtered off
6. customThe aqueous layer was separated
7. additionto the solution was added 35 mL of ethanol
8. additionThereto was added 15 mL of water, which
9. stirringwas then stirred at 40° C
10. additionThereto was added 30 mL of water, which
11. stirringwas stirred
12. temperatureAfter that, it was cooled
13. filtrationThe precipitate was collected by filtration