反応 #41162

反応方程式

5-Chloro-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester

Lithium hydroxide

water

→

5-chloro-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid

収率 99.1%

溶媒

methanol

反応条件

後処理

1. 1
   温度After cooling to room temperature
2. 2
   濃縮the mixture was concentrated
3. 3
   その他to remove the methanol
4. 4
   workup.ADDITIONTetrahydrofuran was added to the residue
5. 5
   その他removed in vacuo
6. 6
   その他removal of the methanol
7. 7
   workup.ADDITIONThe aqueous residue was treated with 6N HCl (1.88 mL)
8. 8
   その他resulting in the precipitation of a thick milky solid
9. 9
   ろ過The solid was collected by filtration
10. 10
    洗浄washed with water
11. 11
    その他dried under high vacuum
12. 12
    温度with heat

実験手順

5-Chloro-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (2.194 g (98%), 8.31 mmol) was dissolved in methanol (12.5 mL). Lithium hydroxide (0.274 g, 11.44 mmol) and water (12.5 mL) were added and the mixture was heated at 80° C. for 1 hour. After cooling to room temperature, the mixture was concentrated to remove the methanol. Tetrahydrofuran was added to the residue and removed in vacuo to ensure complete removal of the methanol. The aqueous residue was treated with 6N HCl (1.88 mL) resulting in the precipitation of a thick milky solid. The solid was collected by filtration, washed with water and dried under high vacuum with heat to give 5-chloro-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid (1.900 g, 99%). Mass spectrum: m/z: 231.30 (M+H).

出典