反应详情

To a solution of 5-methyl-3-phenyl-isoxazole-4-carboxylic acid (5.00 g, 24.6 mmol) in THF (50 mL) was added in one portion 1,1′-carbonyl-diimidazole (4.39 g, 27.1 mmol). After stirring for 15 min at ambient temperature the solution was warmed to 70° C. and stirred for 30 min at this temperature. After the solution was cooled to 0° C. hydrazine monohydrate (2.4 mL, 49.0 mmol) was added over a period of 2 min while the temperature raised to 15° C. The resulting suspension was stirred for 30 min at 0° C. After addition of 20 mL heptane the suspension was stirred for 15 min at 0° C. and filtered off. Washing with water and drying afforded the title compound (4.52 g, 85%) as a white solid. MS: m/e=218.2 [M+H]+.

1. temperaturewas warmed to 70° C.
2. stirringstirred for 30 min at this temperature
3. additionwas added over a period of 2 min while the temperature
4. temperatureraised to 15° C
5. stirringThe resulting suspension was stirred for 30 min at 0° C
6. stirringwas stirred for 15 min at 0° C.
7. filtrationfiltered off
8. washWashing with water
9. customdrying