反应详情

Alternate procedure: Cool a solution of 5-cyclopropyl-3-(2,6-dichloro-phenyl)-isoxazole-4-carboxylic acid methyl ester (62.4 g, 200 mmol) in dichloromethane (400 mL) to 0° C. Add diisobutylaluminum hydride (440 mL, 1.0 M, 440 mmol) while maintaining the temperature between −5° C. and 0° C. Stir the resulting mixture for 30 min. Warm to 15° C. to 25° C. and stir for 3 h. Add the reaction solution to 2.0 M HCl (800 mL) at ˜8° C. to 10° C. Stir for 30 minutes Separate the phases and extract the aqueous phase with dichloromethane (200 mL). Wash the combined organic phases with water (3×100 mL). Concentrate the organic phase to 180 mL total volume. Add heptane (350 mL). Filter the resulting solid to afford 51.5 g (90%) of the title compound.

1. temperatureWarm to 15° C. to 25° C.
2. stirringstir for 3 h
3. stirringStir for 30 minutes
4. customSeparate the phases
5. extractionextract the aqueous phase with dichloromethane (200 mL)
6. washWash the combined organic phases with water (3×100 mL)
7. concentrationConcentrate the organic phase to 180 mL total volume
8. filtrationFilter the resulting solid