反应详情

4-Acetyl-2-phenylthiazole (16.9 g., 0.083 mol) was dissolved in a mixture of 165 ml. CH3CO2H and 65 ml. H2O by warming to 50°. SeO2 (19.4 g., 0.175 mol) was added and the mixture refluxed for 3 hours, then decolorized with activated carbon, filtered, the filtrate concentrated to an oil, the residue taken up in 600 ml. ethyl acetate, washed 2×300 ml. saturated NaHCO3 and 1×300 ml. brine, and stripped to solids (crude hydrate), 16.2 g. The latter (6 g.) was heated to melting (155°) in vacuo for 10 minutes and cooled to yield title product as a glass; 1H-nmr 7.4-7.7 (m, 3H), 7.9-8.2 (m, 2H), 8.8 (s, 1H), 9.9 (s, 1H).

1. temperaturethe mixture refluxed for 3 hours
2. filtrationfiltered
3. concentrationthe filtrate concentrated to an oil
4. washethyl acetate, washed 2×300 ml
5. temperatureThe latter (6 g.) was heated
6. custom(155°)
7. customfor 10 minutes
8. temperaturecooled