反应详情

温度

50 °C

Under argon gas atmosphere, to a solution of the compound prepared in Example 1 (38.7 g) in toluene, acetic acid (14.5 mL) and 60% aqueous solution of hydrazine hydrate (17.7 mL) were sequentially added at 10 to 30° C. of internal temperature. The mixture was stirred for 7 hours at 45 to 55° C. of internal temperature. To the reaction solution cooled to 10 to 30° C. of internal temperature, 2 mol/L hydrochloric acid was added and then the mixture was separated. The aqueous layer was adjusted to pH 6.5 to 7.5 by adding 25 wt % sodium hydroxide. Isopropyl acetate (216 mL) was added to the adjusted aqueous layer. The separated organic layer was concentrated under reduced pressure. The residue was heated, and n-heptane was added. The solution was cooled to 10 to 30° C. of internal temperature. After the crystal was precipitated, the solution was stirred for 30 minutes. Furthermore, n-heptane was added to the solution, and the mixture was stirred for 1 hour. The precipitated crystal was collected by filtration, dried under reduced pressure for 14 hours or more at about 50° C. to give the title compound having the following physical data (35.5 g (94.8 area %); quantitative value: 61% (2 processes)).

1. additionwas added
2. customthe mixture was separated
3. additionby adding 25 wt % sodium hydroxide
4. additionIsopropyl acetate (216 mL) was added to the adjusted aqueous layer
5. concentrationThe separated organic layer was concentrated under reduced pressure
6. temperatureThe residue was heated
7. additionn-heptane was added
8. temperatureThe solution was cooled to 10 to 30° C. of internal temperature
9. customAfter the crystal was precipitated
10. stirringthe solution was stirred for 30 minutes
11. additionFurthermore, n-heptane was added to the solution
12. stirringthe mixture was stirred for 1 hour
13. filtrationThe precipitated crystal was collected by filtration
14. customdried under reduced pressure for 14 hours or more at about 50° C.