反应详情

At room temperature, a mixture of 2.0 g (15 mmol) of 3-phenyl-4H-[1,2,4]oxadiazol-5-one and 30 ml absolute tetrahydrofuran is admixed with stirring with 0.40 g (10 mmol) of a suspension of sodium hydride (60% strength) and then stirred at room temperature for 10 minutes. 1.9 g (10 mmol) of 3,5-dimethylisoxazol-4-sulphonyl chloride are subsequently added, and the mixture is stirred at room temperature for another 20 hours. For work-up, the reaction mixture is poured into 150 ml of water. The resulting mixture is extracted twice with 80 ml of ethyl acetate each time. The combined organic phases are dried over sodium sulphate and concentrated under reduced pressure. The residue that remains is chromatographed over silica gel using methylene chloride as mobile phase. In this manner, 0.3 g (9% of theory) of 4-(3,5-dimethylisoxazole-4-sulphonyl)-3-phenyl-4H-[1,2,4]oxadiazol-5-one is obtained in the form of a colourless solid of melting point 90 to 95 C.

1. stirringthe mixture is stirred at room temperature for another 20 hours
2. extractionThe resulting mixture is extracted twice with 80 ml of ethyl acetate each time
3. dry with materialThe combined organic phases are dried over sodium sulphate
4. concentrationconcentrated under reduced pressure
5. customThe residue that remains is chromatographed over silica gel