反応 #792175

反応方程式

potassium carbonate

Water

ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylate

Ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylate

product

Ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylate

2,2,2-trifluoroethyl trifluoromethanesulfonate

→

title product

Ethyl 1-(3-chloro-2-pyridinyl)-3-(2,2,2-trifluoroethoxy)-1H-pyrazole-5-carboxylate

溶媒

acetonitrile

反応条件

後処理

1. 1
   温度The stirred suspension was then cooled to 5° C.
2. 2
   温度The reaction mixture was warmed to room temperature
3. 3
   温度heated
4. 4
   温度to reflux, at which time thin layer chromatography
5. 5
   その他the reaction
6. 6
   抽出was then extracted with ethyl ether
7. 7
   抽出The ether extract
8. 8
   乾燥was dried over magnesium sulfate
9. 9
   濃縮concentrated

実験手順

To a suspension of ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylate (i.e. product of Step A) (0.8 g, 3 mmol) stirred in dry acetonitrile (15 mL) at −5° C. was added potassium carbonate (0.85 g, 6.15 mmol). The suspension was stirred for 15 minutes at 20° C. The stirred suspension was then cooled to 5° C., and 2,2,2-trifluoroethyl trifluoromethanesulfonate (0.8 g, 3.45 mmol) was added dropwise. The reaction mixture was warmed to room temperature and then heated to reflux, at which time thin layer chromatography showed the reaction to be complete. Water (25 mL) was added to the reaction mixture, which was then extracted with ethyl ether. The ether extract was dried over magnesium sulfate and concentrated to yield the title product compound (1.05 g) as a pale yellow oil.

出典