Reacción #7738

Ecuación de reacción

Sodium hydroxide

4-methylene-pyrazolidine-1-carboxylic acid 1-benzyl ester

(4-Fluorophenyl)acetyl chloride

→

desired product

Rendimiento 62.0%

2-[2-(4-fluorophenyl)acetyl]-4-methylene-pyrazolidine-1-carboxylic acid benzyl ester

Rendimiento 62.0%

Disolventes

water methylene chloride

water

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGto stir for 18 hours after which time the reaction mixture
2. 2
   Otroto separate
3. 3
   ExtracciónThe aqueous layer is extracted with methylene chloride
4. 4
   Otrodried
5. 5
   Filtraciónfiltered
6. 6
   ConcentraciónConcentration in vacuo
7. 7
   Otroaffords the crude product which
8. 8
   Otrois purified over silica (1:3 ethyl acetate/hexane)

Procedimiento

Sodium hydroxide (0.12 g, 3 mmol) is dissolved in a 1:2 water/methylene chloride solution (30 mL) with rapid stirring followed by the addition of 4-methylene-pyrazolidine-1-carboxylic acid 1-benzyl ester, 9, (0.62 g, 2.8 mmol) at room temperature. (4-Fluorophenyl)acetyl chloride (0.39 mL, 4.2 mmol) is added and the reaction is allowed to stir for 18 hours after which time the reaction mixture is diluted with water (10 mL) and the layers allowed to separate. The aqueous layer is extracted with methylene chloride, the organic layers combined, dried, and filtered. Concentration in vacuo affords the crude product which is purified over silica (1:3 ethyl acetate/hexane) to provide 0.54 g (62% yield) of the desired product.

Fuente