反应详情

A mixture of 2-phenyloxazol-4(5H)-one (600 mg, 3.35 mmol) and phenylhydrazine (420 mg, 382 μL, 3.69 mmol) in ethanol (10 mL) was refluxed for 2 h. The reaction mixture was concentrated in vacuo. The obtained suspension was filtered, washed with EtOH and dried in vacuo to give 513 mg of a light yellow solid which proofed to be product. The filtrate was evaporated to give 430 mg of a yellow solid which also contained a considerable amount of product. Thus, the product was obtained after purification of the evaporated filtrate by flash chromatography (using silica gel and an ethyl acetate/dichloromethane gradient) and combination with the precipitated product as light yellow solid (711 mg, 2.83 mmol, 84.4%). MS: M=252.2 (M+H)+

1. temperaturewas refluxed for 2 h
2. concentrationThe reaction mixture was concentrated in vacuo
3. filtrationThe obtained suspension was filtered
4. washwashed with EtOH
5. customdried in vacuo