Reacción #41162

Ecuación de reacción

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

Rendimiento 99.1%

Disolventes

methanol

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaAfter cooling to room temperature
2. 2
   Concentraciónthe mixture was concentrated
3. 3
   Otroto remove the methanol
4. 4
   workup.ADDITIONTetrahydrofuran was added to the residue
5. 5
   Otroremoved in vacuo
6. 6
   Otroremoval of the methanol
7. 7
   workup.ADDITIONThe aqueous residue was treated with 6N HCl (1.88 mL)
8. 8
   Otroresulting in the precipitation of a thick milky solid
9. 9
   FiltraciónThe solid was collected by filtration
10. 10
    Lavadowashed with water
11. 11
    Otrodried under high vacuum
12. 12
    Temperaturawith heat

Procedimiento

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).

Fuente