反应详情

温度

80 °C

A mixture of ketone from step 2 (1.25 g, 4.5 mmol) and bismuth oxide (Bi2O3) (2.7 g, 1.2 equiv.) in acetic acid (20 ml) was warmed to 80° C. for 30 minutes. After cooling, the mixture was filtered through Celite® filter agent and the filtrate was concentrated. The residue was dissolved in hot methanol and filtered. The solvent was concentrated under a nitrogen stream, placed in the refrigerator and the precipitate formed was filtered to give 1 g (83%) of titled dione: m.p. 96°-97° C. Anal. Calc'd. for C15H11FO2S (M.W. 274.31): C, 65.68; H, 4.04; S, 11.69. Found: C, 65.42; H, 3.85; S, 1.42.

1. temperatureAfter cooling
2. filtrationthe mixture was filtered through Celite®
3. filtrationfilter agent
4. concentrationthe filtrate was concentrated
5. dissolutionThe residue was dissolved in hot methanol
6. filtrationfiltered
7. concentrationThe solvent was concentrated under a nitrogen stream
8. customthe precipitate formed
9. filtrationwas filtered
10. customto give 1 g (83%) of titled dione