反应详情

35.1 gm (0.138 mol) of 2-benzoyl-benzo[b]thiophen-3-ol were dissolved in 35 cc of glacial acetic acid, followed by the addition of 39.0 gm (0.506 mol) of ammonium acetate and refluxing for two and a half hours. The still warm mixture was stirred into 300 cc of ice water, whereby a reddish product was precipitated. The solid was filtered off, dried in the air and recrystallized once from 60 cc of toluene. For further purification, it was dissolved in 30 cc of ethyl acetate, and just enough petroleum ether was added to ensure that no further precipitate forms (about 20 cc), after which 20 gm of activated carbon was added, followed by boiling and hot filtering. The pure end product was obtained from the cool filtrate by cooling to +10° C., adding 60 cc of petroleum ether, allowing the mixture to stand for two hours, and then suction-filtering. By concentrating the mother liquors to a volume of 30 cc and prolonged cooling to +10° C., 2.0 gm more of the desired product of the same quality were obtained. The combined crystalline product was thoroughly washed with a total of 20 cc of petroleum ether and freed from solvents in a circulating air drier at +70° C. 23.0 gm (66% of theory) of egg yellow crystals were obtained, m.p. 121.6°-122.5° C., and were found to be identical with the product of Example 1 based on elemental analysis, IR and UV spectra.

1. temperaturerefluxing for two and a half hours
2. customwas precipitated
3. filtrationThe solid was filtered off
4. customdried in the air
5. customrecrystallized once from 60 cc of toluene
6. customFor further purification, it
7. dissolutionwas dissolved in 30 cc of ethyl acetate
8. additionjust enough petroleum ether was added
9. additionafter which 20 gm of activated carbon was added
10. customThe pure end product was obtained from the cool filtrate
11. temperatureby cooling to +10° C.
12. filtrationsuction-filtering
13. concentrationBy concentrating the mother liquors to a volume of 30 cc
14. temperatureprolonged cooling to +10° C.