Реакция #574797

Уравнение реакции

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

Выход 47.8%

Растворители

methylene chloride

tetrahydrofuran

tetrahydrofuran

Условия реакции

Обработка

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
   Другоеevaporated in vacuo
4. 4
   workup.ADDITIONA saturated sodium bicarbonate solution was added to the residue
5. 5
   Экстракцияextracted twice with chloroform (50 ml)
6. 6
   Сушкаdried over magnesium sulfate
7. 7
   Другоеevaporated in vacuo
8. 8
   ДругоеThe residue was chromatographed on silica gel (40 g) with chloroform as an eluent
9. 9
   workup.ADDITIONThe fractions containing the object compound
10. 10
    Другоеevaporated in vacuo

Методика

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), 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.

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