反应详情

To a solution of isoxazole-5-amine (740 mg, 8.80 mmol) and pyridine (2.14 ml, 26.4 mmol) in tetrahydrofuran (10 ml) was added 2,2,2-trichloroethyl chloroformate (1.82 ml, 13.2 mmol) with ice-cooling and the mixture was stirred for 40 minutes with ice-cooling. To the mixture was further added 2,2,2-trichloroethyl chloroformate (1.82 ml, 13.2 mmol) with ice-cooling and the mixture was stirred for 30 minutes with ice-cooling, the reaction mixture was poured into ice-water and the mixture was extracted with ethyl acetate. The extract was washed with water and dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:1) to obtain the desired product (1.23 g, 53.9%) as a solid.

1. temperaturecooling
2. temperaturecooling
3. temperaturecooling
4. stirringthe mixture was stirred for 30 minutes with ice-
5. temperaturecooling
6. extractionthe mixture was extracted with ethyl acetate
7. washThe extract was washed with water
8. dry with materialdried over anhydrous magnesium sulfate
9. distillationthe solvent was distilled off under reduced pressure
10. customThe residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:1)