반응 #41162

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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

수율 99.1%

용매

methanol

반응 조건

후처리

1. 1
   온도After cooling to room temperature
2. 2
   농축the mixture was concentrated
3. 3
   기타to remove the methanol
4. 4
   workup.ADDITIONTetrahydrofuran was added to the residue
5. 5
   기타removed in vacuo
6. 6
   기타removal of the methanol
7. 7
   workup.ADDITIONThe aqueous residue was treated with 6N HCl (1.88 mL)
8. 8
   기타resulting in the precipitation of a thick milky solid
9. 9
   여과The solid was collected by filtration
10. 10
    세척washed with water
11. 11
    기타dried under high vacuum
12. 12
    온도with heat

실험 절차

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).

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