Reacción #1069133

Ecuación de reacción

Isobutyl chloroformate

3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acrylic acid

triethylamine

2-ethylpiperidine

→

1-[3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acryloyl]-2-ethylpiperidine

Rendimiento 47.8%

Disolventes

methylene chloride

tetrahydrofuran

tetrahydrofuran

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGAfter being stirred at the same temperature for 30 minutes
2. 2
   workup.STIRRINGdropwise at -20° C. and the mixture was stirred at -20° C. to 10° C. for 2 hours
3. 3
   Otroevaporated in vacuo
4. 4
   workup.ADDITIONA saturated sodium bicarbonate solution was added to the residue
5. 5
   Extracciónextracted twice with chloroform (50 ml)
6. 6
   ExtracciónThe combined extract
7. 7
   Lavadowas washed with saturated brine (50 ml)
8. 8
   Secadodried over magnesium sulfate
9. 9
   Otroevaporated in vacuo
10. 10
    OtroThe residue was chromatographed on silica gel (40 g) with chloroform as an eluent
11. 11
    workup.ADDITIONThe fractions containing the object compound
12. 12
    Otroevaporated in vacuo

Procedimiento

Isobutyl chloroformate (1.04 g) was added dropwise to a mixture of 3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acrylic acid (trans isomer) (2.0 g) and triethylamine (0.766 g) in methylene chloride (40 ml) and tetrahydrofuran (10 ml) at -20° C. with stirring. After being stirred at the same temperature for 30 minutes, a solution of 2-ethylpiperidine (0.942 g) in tetrahydrofuran (10 ml) was added thereto dropwise at -20° C. and the mixture was stirred at -20° C. to 10° C. for 2 hours. The mixture was warmed to room temperature and evaporated in vacuo. A saturated sodium bicarbonate solution was added to the residue and extracted twice with chloroform (50 ml). The combined extract was washed with saturated brine (50 ml), dried over magnesium sulfate and evaporated in vacuo. The residue was chromatographed on silica gel (40 g) with chloroform as an eluent. The fractions containing the object compound were combined and evaporated in vacuo to give 1-[3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acryloyl]-2-ethylpiperidine (trans isomer) (1.30 g) as an oil.

Fuente